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1	Analytical Chemistry	ABS-14
Comparative Study of Silver Nanoparticles (AgNPs) Synthesized from Purified and Unpurified Ocimum sanctum Leaves Extract and Their Application as a Colorimetric Sensor for Hg2+ Detection Yussi Pratiwi, Fuad Alfan Asyifa, Agus Darmawan, Harfi Amania Khansa, Listya Eka Anggraini, Aneesha Sheik Musthafa Ajeetha Department of Chemistry, Faculty Mathematics and Sciences, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia Department of Chemistry, Faculty Mathematics and Sciences, Universitas Negeri Jakarta, Jakarta 13220, Indonesia Department of Chemistry, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261, Saudi Arabia Department of Chemistry, Karpagam Academy of Higher Education, Coimbature 641021, India Abstract The presence of Hg(II) ions can accumulate in soil and water can harm living organisms, including humans. An alternative method called silver nanoparticles (AgNPs) as a colorimetric sensor can be used to detect the presence of Hg(II) directly on site. Green synthesis of AgNPs using plant extracts has been widely carried out, but research regarding the use of purified and unrefined plant extracts has not been widely carried out. This study presents a comparative evaluation of AgNPs synthesized from purified and unpurified Ocimum sanctum (tulsi) leaf extract, characterize the resulting AgNPs, and evaluate the analytical performance of the sensor modified as nanocomposite. Comparative result revealed that AgNPs synthesized from unpurified extract exhibited smaller size, homogenous, and more colloidal stability, with a size of 66,8 nm, polydispersity index of 0,295, and zeta potential of -26,9 mV. AgNPs synthesized from unpurified extract were modified into nanocomposite film using chitosan-starch to obtain a sensor with high selectivity toward Hg(II) ions, sensitivity in the concentration range of 100 ppm to 50 ppb, and stability for up to four weeks. The nanocomposite film sensor had a LOD of 0.8 ppm and a LOQ of 2.4 ppm. Keywords: colorimetric sensor, mercury, silver nanoparticles, tulsi leaf extract Share Link | Plain Format | Corresponding Author (Harfi Amania Khansa)

2	Analytical Chemistry	ABS-36
Phytochemical Composition, Antioxidant Activity, and Untargeted LC-HRMS Fingerprinting of Coffee Pulp under Different Extraction Approaches Muhammad Eriansyah Al Hakim(a*), Sandi Darniadi(a,b), Anil Kumar Anal(a) (a) Food Innovation Bioprocessing Nutrition and Health, Asian Institute of Technology, Thailand *st125014[at]ait.asia (b) National Research and Innovation Agency (BRIN) Abstract Coffee pulp, a major by-product of coffee processing, represents a promising yet underutilized source of bioactive phytochemicals. The efficiency and selectivity of compound recovery from such biomass are highly dependent on extraction strategy. This study compared the conventional heating, ultrasound assisted extraction (UAE), and microwave assisted extraction (MAE) to determine its methods influence on phenolic recovery, antioxidant potential, and molecular fingerprinting of coffee pulp extracts. The best performing extraction condition from each method was selected and assessed through total phenolic content (TPC), total flavonoid content (TFC), total soluble sugar (TSS), antioxidant activity (DPPH assay), and untargeted LC-HRMS profiling. The results revealed that each methods showing a clear difference in phytochemical profiles and antioxidant response. MAE demonstrated the most phenolic and flavonoid recovery which also have a more enhanced antioxidant activity, indicating a more efficient extraction of bioactive constituents. UAE exhibited intermediate performance, while conventional extraction showed lower enrichment of antioxidant-related compounds. Interestingly, the untargeted LC-HRMS analysis indicated that conventional extraction produced broader chemical feature richness, suggesting extensive co-extraction of matrix components. In contrast MAE generated a more selective molecular fingerprint which reflects a more targeted recovery of phenolic subclasses rather than the other methods. Major phenolic compounds, including chlorogenic acid derivatives and dicaffeoylquinic acid-related structures were consistently detected across al extraction approaches, confirming that extraction method did not alter the core phytochemical composition but rather modulated extraction selectivity and recovery efficiency. Overall, the findings emphasize that each extraction methods significantly shapes both of phytochemical^s profiles and functional antioxidant properties of coffee pulp. MAE in particular, demonstrates strong potential as a selective and efficient approach for valorizing coffee processing by-products within sustainable and green chemistry frameworks. Keywords: Coffee pulp, extraction methods, phenolic compounds, antioxidant activity, LC HRMS, phytochemical profiling Share Link | Plain Format | Corresponding Author (Muhammad Eriansyah Al Hakim)

3	Analytical Chemistry	ABS-38
Removal of Ni(II) Ions from Aqueous System using a Reusable Adsorbent of kappa-Carrageenan Modified with Glutaraldehyde and KCl Ladona Nur Adiana, Muhammad Iqbal, Chika Ayu Salamah, Ayu Zakia Analytical Chemistry Research Group, Institut Teknologi Bandung, Indonesia Abstract The rapid growth of industrial activities has led to a significant increase in the discharge of heavy metal waste, specifically Ni(II) ions, which pose a severe environmental hazard due to their persistent nature and tendency to bioaccumulate within aquatic ecosystems. Adsorption has emerged as one of the most efficient techniques for the Ni(II) ions removal from contaminated waters. kappa-carrageenan, a linear polysaccharide extracted from red seaweed, represents a renewable biomass that has been investigated for its potential as an adsorbent material. However, the application of unmodified kappa-carrageenan is hindered by its solubility in aqueous media, which compromises its structural integrity during the adsorption process. In the present study, kappa-carrageenan was modified using glutaraldehyde (GA) as a cross-linking agent and further stabilized with potassium chloride (KCl) to enhance its structural stability and optimize its specific adsorption properties. The synthesized adsorbent, designated as KCl-treated kappa-carrageenan-GA, was comprehensively characterized via Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS). FTIR analysis revealed shifts in the absorption peaks corresponding to the O-H and O=S=O functional groups, confirming the synthesis of the adsorbent. SEM imaging demonstrated pronounced morphological alterations following the adsorption process, while EDS mapping provided definitive evidence of Ni(II) ion deposition on the adsorbent surface. The optimal parameters for Ni(II) sequestration were established at a solution pH of 4, a contact time of 90 minutes, and an adsorbent dosage of 0.06 g/25 mL. The adsorption kinetics were found to follow a pseudo-first-order model, while the equilibrium data adhered to the Freundlich isotherm model. Furthermore, reusability assessments indicated that the adsorbent maintains its performance over four consecutive adsorption-desorption cycles. In conclusion, these findings demonstrate the potential of the modified kappa-carrageenan as a sustainable, eco-friendly, and cost-effective adsorbent for Ni(II) ions removal from aqueous system. Keywords: kappa-carrageenan, glutaraldehyde, Ni(II) ion, reusable adsorbent Share Link | Plain Format | Corresponding Author (Muhammad Iqbal)

4	Analytical Chemistry	ABS-45
Evaluation of Electrochemically Active Surface Area in rGO/Au Nanoparticle-Modified MIP Sensors for Enhanced Dopamine Detection Tania Amara Dewi1, a *, Henry Setiyanto1,b Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia Abstract This research aimed to develop cheap and fast electrochemical sensors for early diagnosis of neurodegenerative diseases and assessment of Mental Health through point-of-care testing with dopamine detection. Evaluation of the Electrochemically Active Surface Area (ECSA) was carried out on the development of a molecularly imprinted polymer (MIP) sensor based on reduced graphene oxide (rGO) composites and gold nanoparticles (AuNPs) for dopamine detection. Electrode modification is performed in stages through the electrodeposition of rGO and AuNPs, followed by electrochemical polymerization of polypyrrol as a MIP matrix. The determination of the ECSA was carried out using the Randles-Sevcik equation through the cyclic voltammetry (CV) technique in a redox prob solution Electrode modification with rGO/Au Nanoparticle and MIP matrix succeeded in significantly increasing the electrochemical active surface area by 73%, from 6.11 mm2 on a plain electrode to 10.57 mm2. This nearly twofold increase confirms the effectiveness of integrating nanomaterial in providing more active sites for dopamine redox reactions This increase proves the synergistic role of rGO and AuNPs in providing a wider active site and accelerating electron transfer, albeit enclosed by a polymer layer. The developed sensor shows good linearity in the range of nanomolar to micromolar concentrations as well as very high selectivity against interfering compounds such as uric acid, glucose, and ascorbic acid with a ratio of up to 1:1000. This study provides important insights into the correlation between the active surface area of the electrode and the sensitivity and stability of MIP-based electrochemical sensors for biomedical applications. Keywords: electrochemically active surface area- molecularly imprinted polymer- dopamine- electrochemical sensors Share Link | Plain Format | Corresponding Author (Tania Amara Dewi)

5	Analytical Chemistry	ABS-63
Bioavailability and Uptake of Cadmium and Lead in Soil-Plant Systems: A Combined DGT and Sequential Extraction Elfina Rahmania Zelfi Universitas Indonesia Abstract Please Just Try to Submit This Sample Abstract You Can Edit It Again Later Heavy metal contamination in agricultural soils, particularly by cadmium (Cd) and lead (Pb), represents a critical environmental and public health concern due to their toxicity, persistence, and potential for bioaccumulation within the food chain. This study aims to evaluate the bioavailability of Cd and Pb in soil and to assess their uptake and accumulation in spring onion (Allium fistulosum L.) through the integration of sequential extraction and Diffusive Gradients in Thin Films (DGT) techniques. The Tessier sequential extraction procedure was employed to elucidate the distribution of metals among distinct geochemical fractions, while the DGT technique was utilized to quantify the labile and bioavailable metal species under near in situ conditions. The experimental approach comprised soil physicochemical characterization, including pH, cation exchange capacity, organic matter content, and total metal concentrations, followed by sequential extraction analysis and controlled pot experiments with varying Cd and Pb concentrations. The DGT devices were fabricated using Saccharomyces cerevisiae-based biomass as a novel binding agent. Metal concentrations in soil extracts and plant tissues (roots, stems, and leaves) were determined using Atomic Absorption Spectrophotometry (AAS). The findings are expected to demonstrate that Cd and Pb are partitioned into multiple soil fractions with differing degrees of mobility and bioavailability, where the labile fraction significantly influences plant uptake. The DGT technique is anticipated to provide a more reliable estimation of bioavailable metal concentrations compared to conventional extraction methods and to exhibit a strong correlation with metal accumulation in plant tissues. Moreover, the accumulation of Cd and Pb in Allium fistulosum may pose potential risks to environmental sustainability and food safety when concentrations exceed established threshold limits. Overall, the integration of DGT and sequential extraction methods offers a comprehensive approach for assessing heavy metal bioavailability in soils and its implications for crop contamination and human health risk. Keywords: bioavailability, cadmium (Cd), lead (Pb), Diffusive Gradients in Thin Films (DGT), sequential extraction, Allium fistulosum, heavy metals Share Link | Plain Format | Corresponding Author (elfina rahmania zelfi)

6	Analytical Chemistry	ABS-69
Electrochemical Sensor Based on MWCNT-CS/AuNPs-Modified Carbon Paste Electrode for Methyl Paraben Detection Mega Wijayanti Kusumadewi (a*), Henry Setiyanto (b) Analytical Chemistry Research Group, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Indonesia Abstract Methyl paraben is widely used as a preservative in cosmetic and personal care products and has been identified as a potential Endocrine Disrupting Chemicals (EDC), raising concerns regarding its impact on human health and the environment. Therefore, analytical methods are required for the determination of methyl paraben in various matrices. In this study, an electrochemical sensor based on a multi-walled carbon nanotube-chitosan/gold nanoparticles (MWCNT-CS/AuNP)-modified carbon paste electrode (CPE) was developed for the detection of methyl paraben. The modified electrode was prepared by drop-casting an MWCNT-CS composite onto the CPE surface followed by electrodeposition of AuNPs. Cyclic voltammetry was conducted over a range of scan rates in ferri/ferrocyanide redox probe, and the electroactive surface area was estimated based on the Randles-Sevcik equation. The electroactive surface area increased from 6.22 square millimeters for the bare CPE to 18.27 square millimeters for CPE/MWCNT-CS/AuNPs, corresponding to an approximately 2.9 times larger surface area. Quantitative analysis was performed using linear sweep voltammetry over a concentration range of 1-1000 uM. Three linear ranges were obtained at 1-10, 10-100, and 100-1000 uM. The developed sensor exhibited a sensitivity of 1.20 uA/uM cm2, LOD of 0.506 uM, and LOQ of 1.688 uM. The selectivity of the sensor was evaluated in the presence of common cosmetic interferents, AA, HQ, and BHA. The sensor showed over 90% of its initial response even at a methyl paraben-to-interferent ratio of 1:100, showing good anti-interference performance. Furthermore, the electrode showed good storage stability, maintaining 87% of its initial response after 20 days of storage at room temperature. These results show that the MWCNT-CS/AuNP-modified carbon paste electrode provides a promising platform for the sensitive and selective electrochemical detection of methyl paraben. Keywords: electrochemistry- electrode, electroactive surface area- methyl paraben- mwcnt- multi-walled carbon nanotube- chitosan- gold nanoparticles- carbon paste electrode- cyclic voltammetry- AuNPs- endocrin disrupting chemicals Share Link | Plain Format | Corresponding Author (Mega Wijayanti Kusumadewi)

7	Analytical Chemistry	ABS-80
Comparison of Acidic, Alkaline, and Sequential Deep Eutectic Solvent Pretreatment Methods for Crescentia cujete Linn. Fruit Rind Katrina J. Adajar (1,a*), Lemmuel L. Tayo (2,b) 1School of Graduate Studies, Mapua University, Intramuros, Manila, 1002, Metro Manila, Philippines 2School of Health Sciences, Mapua University, Makati City, 1205, Metro Manila, Philippines a*kjadajar[at]mymail.mapua.edu.ph, bLLtayo[at]mapua.edu.ph, Abstract The application of choline chloride-based deep eutectic solvents for efficient lignocellulosic biomass fractionation were studied using different pH range and sequential treatment. Acidic choline chloride and lactic acid, alkaline choline chloride and monoethanolamine, and sequential DES systems with varying molar ratios of 2:1, 1:1, and 1:2 were evaluated for the pretreatment of Crescentia cujete Linn. fruit rind under 1 to 2 h thermal conditions. The effects of key physicochemical properties, particularly pH and viscosity, on delignification and cellulose enrichment were investigated, while FTIR and SEM analyses were employed to examine structural changes in the treated biomass. Results showed that pH and viscosity exert only limited influence on biomass fractionation. A moderate positive correlation between pH and lignin removal with r value equal to 0.38 suggesting that more basic conditions may enhance delignification, whereas viscosity exhibited a comparable negative correlation, indicating improved mass transfer in lower-viscosity systems. However, the model demonstrated low explanatory power with R^2 equal to 0.283 and was not statistically significant, indicating that these factors alone do not strongly govern lignin removal. Similarly, cellulose enrichment showed negligible dependence on pH and viscosity, with very low model fit. Among the treatments, the acidic ChCl and La/1:1 system at 2 h achieved the most balanced performance, yielding 46.23 percent cellulose enrichment and 27.9 percent lignin removal. Although sequential treatments resulted in slightly higher cellulose content of 47.08 percent, they caused substantial hemicellulose degradation, indicating excessive fractionation severity. These findings highlight that solvent composition and treatment conditions play a more critical role than physicochemical properties alone in governing biomass fractionation. Keywords: deep eutectic solvents (DES), sequential pretreatment, lignocellulosic biomass, delignification Share Link | Plain Format | Corresponding Author (Katrina Adajar)

8	Analytical Chemistry	ABS-88
CANDLENUT SHELL-DERIVED GRAPHENE OXIDE FOR ENHANCED IONIC AND MECHANICAL PERFORMANCE OF CMC COMPOSITES Boy Chandra Sitanggang (a,b*), Paulina Taba (a), Sun Theo Constan Lotebulu Ndruru (c), Djabal Nur Basir (a) a) Departemen Kimia, Fakultas MIPA, Universitas Hasanuddin Jl. Perintis Kemerdekaan Km. 10, Tamalanrea, Makassar 90245, Indonesia b) Prodi Analisis Kimia, Akademi Komunitas Industri Manufaktur Bantaeng, Bantaeng, Sulawesi Selatan 92461, Indonesia *boycsitanggang[at]akom-bantaeng.ac.id c) Research Center for Chemistry, Research Organization for Nanotechnology and Materials (ORNM), National Research and Innovation Agency (BRIN), KST B.J. Habibie, Tangerang Selatan, Banten,Indonesia Abstract Achieving simultaneous improvement in ionic conductivity and mechanical performance in polymer composites remains a critical challenge, particularly when using sustainable, bio-derived fillers. In this study, graphene oxide derived from candlenut shell biomass was synthesized via a modified Hummers method and used as filler in carboxymethyl cellulose (CMC) composites with varying loadings (1-5 wt%). Fourier transform infrared analysis confirmed the successful oxidation of biochar. The incorporation of graphene oxide significantly enhanced both ionic conductivity and mechanical properties, with optimal performance observed at 1% filler loading, attributed to the formation of effective ion transport pathways and improved stress transfer. At higher loadings, however, agglomeration effects led to decreased performance, highlighting a non-linear structure-property relationship. These findings demonstrate the potential of candlenut shell-derived graphene oxide as a sustainable and efficient nanofiller for the development of high-performance CMC-based composites for advanced functional applications. Keywords: Biomass, filler, ionic conductivity, graphene oxide, mechanical properties Share Link | Plain Format | Corresponding Author (BOY CHANDRA SITANGGANG)

9	Analytical Chemistry	ABS-92
Synthesis of ZnCl2-Crosslingked Fe3O4 Leucaena leucocephala Peel Chitosan Alginate Nanocomposite Via Coprecipitation for Silymarine Carrier Material Budi Hastuti (a), Ulfiana (a), Saptono Hadi (b) a) Chemistry Education Department, Faculty of Teacher Training and Education, Sebelas Maret University b) Pharmaceutical Department, Faculty of Mathematics and Natural Sciences, Sebelas Maret University Abstract Silymarin is prone to degradation under acidic conditions, necessitating an effective carrier to improve its stability. In this study, a Fe&#8323-O&#8324- chitosan alginate nanocomposite incorporating Leucaena leucocephala peel extract was developed for silymarin delivery. This work aimed to evaluate the effects of dissolution pH and silymarin concentration on its release behavior, as well as to determine the release kinetics. Encapsulation efficiency was determined by immersing the silymarin-loaded nanocomposite for 24 hours. The release study was conducted over 4 hours with variations in dissolution pH and silymarin concentration. The absorbance of the samples was measured using a UV Vis spectrophotometer, and the release data were analyzed using zero order, first order, Higuchi, and Korsmeyer Peppas kinetic models. The nanocomposite was characterized using Fourier Transform Infrared (FTIR), X Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Particle Size Analyzer (PSA). FTIR results showed shifts in the characteristic peaks of chitosan alginate and the appearance of a new peak at 555.8 corresponding to FeO vibrations. XRD analysis indicated that the nanocomposite exhibited an amorphous structure Keywords: Nanocomposite- chitosan- alginate- Fe3O4- Leucaena leucocephala-silymarine Share Link | Plain Format | Corresponding Author (Ulfiana )

10	Analytical Chemistry	ABS-94
Synthesis and Application of Chitosan-Pectin-Polyvinyl Alcohol as Dialysis Membrane for Creatinine and Urea Transport Budi, Hastuti (a*), Salsabila, Flavia (a), Hadi, Saptono (b) Kamari, Azlan (c) Febriliana Mitha, Amanda (a) a) Department of Chemistry Education, Faculty of Teacher Training and Education, Sebelas Maret University, Surakarta, Central Java. INDONESIA b) Department of Pharmacy, Faculty of Mathematics and Natural Science, Sebelas Maret University, Surakarta, Central Java. INDONESIA c) Department of Chemistry Education, Faculty of Teacher Training and Education, University of Pendidikan Sultan Idris. MALAYSIA Abstract Biomembrane applications in the biomedical field continue to increase. Chitosan, a cationic polymer, has potential use as a hemodialysis membrane because it can be readily formed into thin layers. Chitosan is biodegradable and economical, but it has drawbacks, including poor mechanical strength and acid stability. Therefore, chitosan needs to be combined with a biopolymer with a different charge, such as alginate. The combination of chitosan and alginate forms a stable polyelectrolyte complex. The study aimed to synthesize and characterize a chitosan-pectin-poly(vinyl alcohol) (Chi-Pec-PVA) membrane for hemodialysis. The morphological, thermal, and mechanical characterization of the membrane was performed by Tensile Test, Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The membrane^s efficiency for creatinine transport from aqueous solution was tested using a batch method. The results showed that the Chi-Pec-PVA membrane was successfully synthesized. The membrane was identified as a semicrystalline phase present in the microspheres. The addition of PVA increases the membrane^s mechanical strength, as measured in the tensile test. The creatinine clearance was 93.1% and the urea reduction ratio was 91.3%, indicating good selectivity of the Chi-Pec-PVA as a hemodialysis membrane. Keywords: Chitosan- Pectin, Polyvinyl Alcohol, Creatinine, Urea Share Link | Plain Format | Corresponding Author (Febriliana Mitha Amanda)

11	Biochemistry	ABS-6
Techno-Economic Assessment and In Silico Study of Ethanol-Water Extracted Melinjo (Gnetum gnemon) for Antidiabetic Applications Kayla Nasya Tsabita(#1) , Nadine Alifyarini(#1 ), Andrei Bernadette (1) , Luky Rizky Putra (1), Leon Lukhas Santoso (1), Dewi Tristantini (1*) 1 ) Chemical Engineering, Universitas Indonesia Depok, Indonesia *Corresponding author: detris[at]che.ui.ac.id #All authors contributed equally Abstract The increasing prevalence of diabetes mellitus, a disease that occurs during periods of prolonged hyperglycemia, especially in developing countries, urges the development of cost-effective and accessible therapeutic alternatives. Melinjo (Gnetum gnemon), an indigenous Indonesian plant rich in polyphenols and flavonoids such as resveratrol, quercetin, and kaempferol, has demonstrated potential antidiabetic properties. Using an ethanol-water solvent system, this study integrates in silico molecular docking, enzymatic inhibition modeling, and preliminary techno-economic plant design to evaluate the feasibility of producing antidiabetic melinjo extract. To evaluate interactions between key bioactive compounds and three diabetes-related target proteins, 11-\(\beta\)-hydroxysteroid dehydrogenase-1 (4K1L), interleukin-1\(\beta\) (2NVH), \(\alpha\)-amylase (4W93), molecular docking simulations were performed using MOE 2014.09. The results indicate favorable binding affinities and inhibition constants, which suggest non-competitive inhibition mechanisms consistent with Michaelis-Menten modeling. Process simulation was conducted using SuperPro Designer v.13 to design a batch extraction plant with decoction and oven-drying processes. The projected annual production capacity reached 174,197 bottles at a selling price of IDR 300,000 (USD 20) per bottle. Economic analysis demonstrated strong investment feasibility with ROI of 152%, IRR of 112%, NPV of IDR 54.38 billion (USD 3.53 million), PBP of 1.03 years, and BEP of 69,918 bottles. Results confirm both the biological inhibition potential and economic viability of melinjo extract as a natural antidiabetic product. This study provides a systematic framework linking computational bioactivity validation with industrial process design and financial feasibility, supporting the development of scalable herbal-based therapeutics in Indonesia. Keywords: melinjo extract- antidiabetic- molecular docking- process simulation- in silico Share Link | Plain Format | Corresponding Author (Kayla Nasya Tsabita)

12	Biochemistry	ABS-7
Nanoemulsions Containing Cosmos caudatus Kunth Extract: Formulation and Characterization for Antioxidant Potential Izaz Aqeiluz Zahara,a,1 Siti Mariyah Ulfa,a,2 Noraini Ahmad,b,3*Anna Safitria,c,4* aDepartment of Chemistry, Faculty of Mathematics and Natural Sciences, Brawijaya University, Jl. Veteran, Malang 65145, East Java, Indonesia bDepartment of Chemistry, Faculty of Science, University of Malaya, 50603 Lembah Pantai, Kuala Lumpur, Malaysia cResearch Centre of SMONAGENES (Smart Molecules of Natural Genetic Resources), Brawijaya University, Jl. Veteran, Malang 65145, East Java, Indonesia Coreresponding email: a.safitri[at]ub.ac.id Abstract Plant derived antioxidants have attracted considerable scientific interest due to their therapeutic potential. However, their application in clinical and pharmaceutical settings is frequently hindered by low water solubility, physicochemical instability, and limited bioavailability, all of which compromise their biological efficacy. Leaves of Cosmos caudatus K. are rich in flavonoids known for strong radical scavenging activity. Despite these benefits, such polyphenolic constituents are prone to degradation and display poor dispersion in aqueous environments, restricting their stability and delivery efficiency. This study aimed to formulate and optimize a nanoemulsion encapsulating C. caudatus extract using the low energy Phase Inversion Composition (PIC) method. Optimization was performed through Response Surface Methodology employing a three factor Central Composite Design to assess the effects of medium chain triglyceride (MCT) oil, Tween 80, and Span 80 on droplet size, polydispersity index (PDI), and loading capacity. The optimized formulation (1 MCT oil, 0.85 Tween 80, 0.25 Span 80) generated nanosized droplets (106.6 nm) with narrow size distribution (PDI 0.205) and a loading capacity of 56.52 percent. Transmission electron microscopy confirmed spherical morphology and homogeneous dispersion. The system exhibited measurable antioxidant activity, with IC50 values of 94.93 (DPPH), 75.45 (FRAP), and 82.03 (H2O2 scavenging). Although nanoemulsification did not significantly enhance intrinsic antioxidant potency compared with the crude extract, it substantially improved dispersion characteristics and physicochemical stability. These findings demonstrate that PIC assisted nanoemulsification combined with statistical optimization represents a rational lipidbased delivery strategy for flavonoid rich antioxidants with potential pharmaceutical and nutraceutical applications. Keywords: Nanoemulsion, Cosmos caudatus Kunth, Antioxidant, Tween 80, Span 80 Share Link | Plain Format | Corresponding Author (Izaz Aqeiluz Zahara)

13	Biochemistry	ABS-8
Formulation, Stability, and pH-Responsive Release of Freeze-Dried Microcapsules Containing Averrhoa bilimbi L. Leaf Extract Anna Safitri[1, 2], Sutrisno Sutrisno[1], Kana Mardhiyyah[3,4], Kholaf Athallah Vyanto[1], Wasilia Wulandari[1] 1. Department of Chemistry, Faculty of Mathematics and Natural Sciences, Brawijaya University, Jl. Veteran, Malang, 65145, Indonesia 2. Research Centre of SMONAGENES (Smart Molecules of Natural Genetic Resources), Brawijaya University, Jl. Veteran, Malang, 65145, Indonesia 3. Department of Biochemistry & Biomolecular, Faculty of Medicine, Universitas Brawijaya, 65145 Malang, East Java, Indonesia 4. Master Program in Biomedical Science, Faculty of Medicine, Universitas Brawijaya, 65145 Malang, East Java, Indonesia Abstract The instability and limited bioavailability of flavonoid-rich plant extracts remain major challenges for their application in functional food and pharmaceutical systems. This study aimed to optimize the microencapsulation of Averrhoa bilimbi L. ethanolic leaf extract using sodium alginate through Response Surface Methodology based on a Central Composite Design. Alginate concentration (0.5 to 2.5 percent w/v) and stirring time (5 to 70 min) were evaluated as independent variables affecting encapsulation efficiency. The optimized condition (1.5 percent alginate and 37.5 min stirring) achieved a maximum encapsulation efficiency of 81.12 percent, with a highly significant quadratic model (R2 = 0.9810). Scanning Electron Microscopy analysis revealed irregular but structurally intact microcapsules with particle sizes ranging from 7.87 to 11.68 um, characteristic of freeze-dried systems. Fourier Transform Infrared spectra confirmed successful ionic cross-linking between alginate and Ca2+, as well as the presence of flavonoid functional groups within the matrix. Antioxidant evaluation showed strong radical scavenging activity, while pH dependent release studies demonstrated limited release under acidic conditions (26.30 percent at pH 2.2) and significantly enhanced release at intestinal pH (67.79 percent at pH 7.4). Kinetic modeling indicated a transition from diffusion controlled release under gastric conditions to swelling assisted transport at intestinal pH. Stability studies over four weeks revealed markedly improved antioxidant retention in microcapsules compared to non-encapsulated extract, particularly under cold storage. Overall, this study demonstrates that RSM optimized alginate microencapsulation effectively enhances the stability and controlled intestinal release of A. bilimbi L. flavonoids, highlighting its potential for nutraceutical and functional food applications. Keywords: alginate- antioxidant- Averrhoa bilimbi L.- microencapsulation- RSM- controlled release- stability Share Link | Plain Format | Corresponding Author (Anna Safitri)

14	Biochemistry	ABS-9
Extraction of Ulvan from Ulva reticulata and Its Development into Edible Film and Non-Edible Ulvan-Polyhydroxybutyrate (PHB) Composite Film for Environmentally Friendly Bioplastic Applications Pricilia Amfotis (a), Rukman Hertadi (a*) Biochemistry and Biomolecular Engineering Research Division, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Indonesia *rhertadi[at]itb.ac.id Abstract The increase in conventional plastic waste has driven the search for environmentally friendly bioplastic alternatives. This study aims to extract ulvan from \textit{Ulva} biomass and develop edible film and non-edible ulvan--PHB composite film, along with evaluation of their chemical properties, morphology, and functional performance. Ulvan was extracted using the hot water method (\SI{80}{\celsius}) with varying times of 2--20 hours- the highest yield of \SI{15.85}{\%} was obtained at 12 hours. Edible film was prepared from \SI{3}{\%} (w/v) ulvan with \SI{1}{\%} (w/v) xylitol and \SI{10}{\%} (w/w) citric acid, while non-edible film was prepared from a mixture of ulvan and PHB. FTIR spectra of ulvan revealed characteristic bands of sulfated polysaccharides, supported by H-NMR confirming the ulvan sugar backbone. FTIR of edible film showed dominant O--H, COO-^--, and C--O--C bands, indicating a hydrogen-bonded network, while non-edible film displayed a diagnostic ester C=O band at \SI{\sim 1724}{cm^{-1}} from PHB alongside the ulvan O--H band, confirming composite formation. All samples were characterized using SEM, FTIR, and evaluated for biodegradability, antibacterial activity, and solubility. Overall, ulvan with an optimal yield at 12 hours, along with the utilization of extraction residue for PHB production, demonstrates an integrated \textit{Ulva} biomass-based approach for producing film materials with potential sustainable packaging applications. Keywords: bioplastics, ulvan, polyhydroxybutyrate, film characterization, food packaging Share Link | Plain Format | Corresponding Author (Pricilia Amfotis)

15	Biochemistry	ABS-21
Enzymatic Delignification Technology for Bioethanol Production from Ulva reticulata Macroalgae Patrisius Maryanto Bria (a), Dimas Andrianto (a), R. Haryo Bimo Setiarto (b*) (a) Biochemistry Department, IPB University, Jl. Bungur No.1, Babakan, Dramaga, Bogor, West Java 16680, Indonesia (b) Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN) Indonesia, Jl. Raya Jakarta-Bogor Km.46, Cibinong, Bogor, West Java, 16911, Indonesia Abstract Ulva reticulata shows great potential as a third-generation biomass for producing bioethanol due to its carbohydrate fractions that contain cellulose and hemicellulose. Nonetheless, the presence of lignin hinders the efficiency of hydrolysis and makes the fermentable polysaccharides less accessible. As a result, an effective delignification process is necessary before hydrolysis and fermentation can take place. The goal of this research was to identify and assess effective enzymatic delignification methods for U. reticulata through a systematic literature review following the PRISMA 2020 guidelines. The review looked into key extracellular ligninolytic enzymes, including laccase, lignin peroxidase (LiP), manganese peroxidase (MnP), and versatile peroxidase (VP), evaluating them based on their catalytic processes, operational needs, and significance for bioethanol production. The findings indicate that fungal laccase, especially from white-rot fungi like Pleurotus species, is a strong potential option for delignification because it offers a relatively mild and eco-friendly oxidation system using molecular oxygen, which results in water as the main by-product. However, direct evidence of its application on U. reticulata is currently scarce. Therefore, additional experimental investigations are necessary to confirm its delignification ability and refine its application for bioethanol production. Keywords: bioethanol- enzymatic delignification- laccase- ligninolytic enzymes- Ulva reticulata- white-rot fungi Share Link | Plain Format | Corresponding Author (Patrisius Maryanto Bria)

16	Biochemistry	ABS-27
The Potential of Indonesian Macroalgae as Natural Biostimulants: Analysis of Phytohormone Composition and Its Effect on the Growth of Solanum lycopersicum Mirnawati Dewinda Rumalean Ansanai1*, Rukman Hertadi1 1 Biochemistry and Biomolecular Engineering Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia *Corresponding author: mirnawatidewinda[at]gmail.com Abstract The mounting national demand for food necessitates the development of innovative and sustainable cultivation technologies, including the use of marine-based biostimulants. This study aims to characterize the phytohormone content of three Indonesian macroalgae species (Ulva sp., Sargassum sp., and Gracilaria sp.) and to evaluate their effects on the early growth of tomato plants (Solanum lycopersicum). Bioactive compounds were extracted using an optimized hot water extraction method (1:20 w/v ratio at 80 C for 4 hours). Quantitative analysis of phytohormones was conducted using colorimetric and spectrophotometric methods. The results showed that Sargassum sp. extract (SE) significantly stimulated root growth (4.90 +/- 0.40 cm) at 20 percent concentration, associated with auxin content of 0.37 mg/L and gibberellin content of 1.32 mg/L. Meanwhile, application of 20 percent Gracilaria sp. extract (GE) produced the highest plant height (9.03 +/- 0.152 cm), corresponding to higher gibberellin levels (4.65 mg/L) and cytokinin contents, including zeatin (5.81 mg/L) and kinetin (5.44 mg/L). These physiological responses indicate that species-specific phytohormone composition plays an important role in regulating organ-specific plant growth. The findings highlight the potential of Indonesian macroalgae as effective organic biostimulant sources to support sustainable crop productivity. Keywords: Biostimulants, Phytohormones, Macroalgae, Spectrophotometry, Solanum lycopersicum. Share Link | Plain Format | Corresponding Author (Mirnawati Dewinda Rumalean Ansanai)

17	Biochemistry	ABS-30
Evaluating the changes in metabolomic profiles of Streptomyces sp. in response to signaling molecules from another bacterium Michelle Marie T. Ochoa (a*,b), Hiyas A. Junio, Ph.D. (a), and Lilibeth A. Salvador, Ph.D. (b) a) Institute of Chemistry, College of Science, University of the Philippines, Diliman, Quezon City, 1101, Philippines. *mtochoa[at]up.edu.ph b) Marine Science Institute, College of Science, College of Science, University of the Philippines, Diliman, Quezon City, 1101, Philippines. Abstract The genus Streptomyces is a source of diverse small molecules due to a high number of biosynthetic gene clusters (BGCs) in its genome. However, under normal laboratory culture conditions, these BGCs may be silenced, becoming cryptic. An untargeted coculture elicitation approach was used to evaluate changes in the secondary metabolites of Streptomyces in response to foreign signaling molecules. Streptomyces was cultured in the presence of small molecules from another bacterium to mimic potential environmental interactions between microorganisms. Streptomyces sp. was incubated at normal conditions (R2A medium), low (9:1 R2A medium: cell-free extract), and high (1:1 R2A medium:cell-free extract) ratios. Crude extracts from the three Streptomyces fermentation conditions were obtained by solvent partitioning with ethyl acetate and were profiled using ultrahigh performance liquid chromatography tandem mass spectrometry with a quadrupole time-of-flight mass analyzer (UHPLC-qTOF). MS data were analyzed using online platforms such as Global Natural Products Social Molecular Networking (GNPS) for compound identification and molecular networking, and MetaboAnalyst 6.0 for statistical evaluation between culture conditions. Relative quantitation of selected compounds was also performed using multiple reaction monitoring (MRM). Molecular networking revealed that this Streptomyces sp. strain produced three major classes of compounds: polycyclic tetramate macrolactams (PTM), cyclodepsipeptides, and macrotetrolides. Statistical analysis showed that the relative concentrations of the identified compounds in Streptomyces sp. coculture differ significantly from those in normal culture conditions. As such, varying the composition of the culture medium to incorporate signaling molecules from other bacteria may be a possible means of altering the biosynthetic ability of Streptomyces. Keywords: Natural products, secondary metabolites, metabolomics, mass spectrometry, symbionts, bacteria Share Link | Plain Format | Corresponding Author (Michelle Marie Ochoa)

18	Biochemistry	ABS-33
The profile of FAME synthesized through transesterification of algal oil by lipase from Streptomyces atrovirens TTO26 Yati Sudaryati Soeka, Tri Ratna Sulistiyani, Suciatmih, Novik Nurhidayat, Evi Triana, Titin Yulinery, Siti Mariam, Joko Sulistyo Research Center for Applied Microbiology, National Research and Innovation Agency (NRIA), Indonesia Abstract Microalgal oil is regarded as a promising lipid source and is widely recognized for biodiesel production. These lipids are generally extracted using chemical solvents. Nevertheless, the application of such solvents involves considerable safety concerns. The precautions are essential to minimize potential hazards associated with such processes. There is an urgent need to develop extraction strategies that are safe, economically feasible, robust, efficient, selective, environment friendly, suitable for large-scale implementation, and preventing product contamination. Enzymatic approaches not only addressed these challenges but also provide the additional benefit of high lipid recovery and minimal degradation of target compounds, attributable to their high catalytic specificity. This study was conducted to determine the fatty acid methyl ester (FAME) profile generated through the transesterification of fatty acids isolated from Spirulina fusiformis using a lipase enzyme from Streptomyces atrovirens TTO26. The findings demonstrated that chemical esterification employing BF&#8323- hydrolysed the algal oil into C8 (caprylic acid) at 4.8%, C10 (capric acid) at 5.15%, C12:0 (lauric acid) at 46.94%, C14 (myristic acid) at 21.40%, C18 (stearic acid) at 10.26%, and C22:1 (erucic acid) at 12.07%. Enzymatic transesterification using an immobilized enzyme produced FAME comprising C8 (6.32%), C10 (6.80%), C12:0 (0.03%), C12:1 (39.71%), C14 (0.03%), C16 (20.97%), C18 (11.74%), and C22:1 (14.39%). Meanwhile, the precipitated enzyme yielded C8 (0.70%), C10 (0.66%), C12:0 (0.002%), C12:1 (3.89%), C14 (0.003%), C16 (2.07%), C18 (1.20%), and C22:1 (1.48%). Overall, enzymatic transesterification using immobilized and precipitated enzymes derived from S. atrovirens TTO26 resulted in the production of lauroleic acid (C12:1) at 39.71% and 3.89%, and palmitic acid (C16) at 20.97% and 2.07%, respectively. These FAME components were not detected when chemical esterification with BF&#8323- was applied. Conversely, chemical catalysis led to substantially higher levels of lauric acid (C12:0) and myristic acid (C14), reaching 46.94% and 21.40%, respectively, compared with the enzymatic transesterification process Keywords: algal oil, FAME, lipase, transesterification, Streptomyces atrovirens Share Link | Plain Format | Corresponding Author (Evi Triana)

19	Biochemistry	ABS-39
LC-HRMS Profiling and Integrated In Silico-In Vitro Evaluation of Phenolics, Flavonoids, Antioxidant, and Cytotoxic Activities of Typhonium flagelliforme Leaves Against MCF-7 Cells Dede Komarudin (a), Abdul Mun im (a*), Marissa Angelina (b), Ermin Katrin (c), Susanto Susanto (c), Yulis Adriana (d), Hendig Winarno (c) a Faculty of Pharmacy, Universitas Indonesia, Depok, 16424, West Java, Indonesia b Research Center for Pharmaceutical Ingredient and Traditional Medicine, National Research and Innovation Agency (BRIN), KST Soekarno, Cibinong, Jawa Barat, 16911, Indonesia c Research Center for Radiation Process Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, KST. B.J. Habibie, South Tangerang, 15314, Indonesia d Department of Pharmacy, Institute Science and Technology Al-Kamal, South Kedoya, Kebon Jeruk, West Jakarta, 11520, Indonesia a* munim[at]farmasi.ui.ac.id Abstract Typhonium flagelliforme (TF) is a medicinal plant from Indonesia belonging to the Araceae family, it is claimed to have potential as an anticancer agent. This study aims to characterize the phytochemical profile of TF leaves via Liquid Chromatography High-Resolution Mass Spectrometry, both in silico and in vitro to assess cytotoxic effects on the MCF-7 breast cancer cell line. This study measured the antioxidant activity, total phenolic content (TPC), and total flavonoid content (TFC) of TF leaves extract. The extract was prepared using n-hexane, ethyl acetate, and ethanol as solvents via gradient maceration. Cytotoxicity testing of MCF-7 cells using trypan blue staining yielded IC50 values of 28.37 ppm for the n-hexane extract, 19.82 ppm for the ethyl acetate extract, and 24.38 ppm for the ethanol extract. Phytochemical analysis showed the presence of isovitexin (NP-018730), 5,7-Dihydroxy-2-(4-hydroxyphenyl)-6,8-bis[3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl]-4H-chromen-4-one, schaftoside, (1E)-1,5-Anhydro-1-[2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-8-yl]-D-galactitol, and corymboside in the ethyl acetate extract. Results of ligand-receptor docking on the estrogen alpha receptor in MCF-7 cells indicated that (1&#958-)-1,5-Anhydro-1-[2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-8-yl]-D-galactitol and isovitexin exhibits a strong binding affinity. The ethyl acetate has antioxidant activity of 87.57 ppm, TPC of 61.55 mg GAE/g, and TFC of 35.08 mg QE/g. Ethyl acetate is a potential test material based on cytotoxicity screening tests on MCF-7 cells and all tests conducted. Keywords: Cytotoxicity, In silico, In vitro, MCF-7, Typhonium flagelliforme Share Link | Plain Format | Corresponding Author (Dede Komarudin)

20	Biochemistry	ABS-41
MOLECULAR DOCKING STUDY OF ANILINE- AND BENZYLAMINE-SUBSTITUTED PYRAZINE DERIVATIVES COMPOUND AS ANTIBACTERIAL CANDIDATES Zainudin Saputra, Widiastuti Agustina Eko Setyowati Sebelas Maret University Abstract Antibiotic resistance has increased significantly, reducing the effectiveness of treatment for bacterial infections. In 76 countries, the average resistance of Escherichia coli to third-generation cephalosporins reached 42%, while Staphylococcus aureus resistance to methicillin was 35%. S. aureus, Staphylococcus epidermidis, and Methicillin-Resistant Staphylococcus aureus are pathogenic bacteria that frequently cause various infections ranging from mild to severe. Pyrazine is an aromatic heterocyclic compound with potential as an antibacterial framework, but requires structural modification. Substitution of aniline and benzylamine groups was chosen to enhance molecular interactions, binding affinity, and antibacterial activity. This study aims to understand the molecular interactions between pyrazine derivatives substituted with aniline and benzylamine groups with bacterial target proteins of S. aureus, S. epidermidis, and MRSA through molecular docking analysis using Autodock Tools, visualized with Discovery Studio Biovia and pymol, and accompanied by pharmacokinetic and toxicity predictions via the SwissADME and Protox-II websites. The test ligands used were 3-amino-N(4-chlorophenyl)pyrazine-2-carboxamide[1], 3-amino-N-(4-bromophenyl)pyrazine-2-carboxamide[2], 3-amino-N-(4-chlorobenzyl)pyrazine-2-carboxamide[3], 3-amino-N(3 chlorobenzyl)pyrazine-2-carboxamine[4], 3-amino-N-(2,4-dichlorobenzyl)pyrazine-2-carboxamide[5], 3-amino-N-(3-fluorobenzyl)pyrazine-2-carboxamide[6], 3-amino-N-(4-fluorobenzyl)pyrazine-2-carboxamide [7] each targeted at proteins with PDB ID 4CJN (MRSA), 4M8I (S. Epidermidis), and 3G75 (S. aureus). Molecular docking results showed that test ligand 7 had the best affinity for MRSA (-5.6 kcal/mol), test ligand 4 toward S. epidermidis (-7.9 kcal/mol), and test ligand 6 toward S. aureus (-6.7 kcal/mol). All compounds meet Lipinskis and Vebers rules with a bioavailability score of 0.55. Based on these results, it is known that compound 7 for MRSA, 4 for S. epidermidis, and 6 for S. aureus are considered the best drug candidates based on molecular docking exploration and ADMET predictions and are recommended for further testing in vitro and in vivo. Keywords: Antibacterial- MRSA- Staphylococcus aureus- Staphylococcus epidermidis- Aniline-substituted and benzylamine-substituted pyrazine derivatives- Molecular docking Share Link | Plain Format | Corresponding Author (Zainudin Saputra)

21	Biochemistry	ABS-72
Thermal Induced Physicochemical Changes and Formation of 3-MCPD and Glycidyl Esters in Re-esterified Palm Mesocarp Oil (RPMO) Olein Tuti Ariyani, Budiawan Department of Chemistry, University of Indonesia Abstract Thermal processing of palm oil may induce significant physicochemical changes and lead to the formation of process contaminant that affect oil quality and safety, particularly in restructured oils such as reesterified palm mesocarp oil (RPMO). This study aimed to evaluate the effect of heating duration on physicochemical properties and contaminant formation in RPMO olein. RPMO olein samples were subjected to heating at 200 C for 30, 60, and 90 minutes. The evaluated parameters included free fatty acid (FFA), iodine value (IV), peroxide value (PV), total tocopherol, total carotenoid, as well as 3-monochloropropane-1,2-diol (3-MCPD) and glycidyl esters (GE). The results showed that heating significantly affected the physicochemical characteristics of RPMO olein. FFA increased progressively from 0.37% to 0.93%, indicating enhanced hydrolysis during prolonged heating. IV decreased from 59.59 to 55.74, suggesting a reduction in unsaturation levels. PV increased initially from 0.84 to 2.80 meq/kg at 60 minutes, followed by a decrease to 1.41 meq/kg at 90 minutes, indicating the decomposition of primary oxidation products into secondary oxidation compounds. The content of natural antioxidants decreased markedly with heating duration. Total tocopherol decreased from 1354.61 to 955.40 ppm, while total carotenoid showed a substantial reduction from 348.84 to 47.68 ppm. Furthermore, process contaminants were formed during heating, with 3-MCPD and GE reaching maximum levels at 60 minutes before declining at prolonged heating. These findings demonstrate that prolonged thermal exposure significantly deteriorates oil quality and promotes contaminant formation, highlighting the importance of controlling thermal processing conditions to ensure the safety and stability of RPMO-based products. Keywords: Re-esterified palm mesocarp oil (RPMO), heating treatment, physicochemical properties, oxidative degradation, 3-MCPD, glycidyl esters Share Link | Plain Format | Corresponding Author (Tuti Ariyani)

22	Biochemistry	ABS-73
Calcium Imaging Identifies Neuroactive Natural Products from Philippine Seaweeds Franches Rigel B. Jalos (a*), Michael Y. Roleda (a), and Lilibeth A. Salvador-Reyes (a) (a) Marine Science Institute, University of the Philippines Diliman, Quezon City, Philippines Abstract The Philippines ranks among the worlds leading seaweed producers and harbors over 1,065 taxa of marine macroalgae. Seaweeds have long been utilized for diverse applications, including as food, fertilizers, animal feed, and in traditional medicine for the management of various conditions such as rheumatoid arthritis, asthma, cough, diarrhea, abdominal pain, and goiter. In this study, 57 species collected from seven provinces in the Philippines were evaluated for neuroactivity using the Dorsal Root Ganglion (DRG) assay. DRG neurons isolated from 20 to 60 days postnatal ICR mice were loaded with the calcium-sensitive Fura 2AM dye and monitored using calcium imaging. Intracellular calcium levels were measured through alternating excitation at 340 and 380 nm in response to KCl stimulation. Following treatment, the 340/380-nm ratiometric calcium traces revealed that 27 seaweed extracts displayed neuroactivity at 1 ug/mL, with at least 40% of the DRG neurons showing a response. The extracts exhibited distinct neuroactive profiles: 21 induced an increase in intracellular calcium levels in DRG neurons, whereas 6 inhibited calcium influx. These results reveal the neuroactive potential of natural products derived from Philippine seaweed extracts, offering promising avenues for neuroscience and biotechnological applications. Keywords: Philippine seaweeds, natural products, neuroactivity, Dorsal Root Ganglion Assay, calcium imaging Share Link | Plain Format | Corresponding Author (Franches Rigel Jalos)

23	Biochemistry	ABS-82
Antiproliferation Activity of Indonesia Acacia Honey in Inducing Apoptosis of Colon Cancer Cells Yoggi Ramadhani Purwaningtyas1, Dimas Andrianto3, Mega Safithri3, Sela Septima Mariya4, Feliza Nahlea1, Indah Fajarwati4, Fitrine Ekawasti5, Putri Reno Intan4, Arizah Kusumawati6, Muhammad Ridwan6, Frans Dany6, Ratih Rinendyaputri6, Novaria Sari Dewi Panjaitan6, Rita Marleta Dewi6, Hasim2* 1Biochemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, West Java, Indonesia 16680. 2Metabolism Division, Department of Biochemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, West Java, Indonesia 16680. 3Bioanalysis Division, Departement of Biochemistry, Faculty of Mathematics and Natural Sciences, IPB University, Bogor, West Java, Indonesia 16680. 4Research Center for Biomedical, National Research and Innovation Agency, Cibinong, West Java, Indonesia 16911. 5Research Center for Veterinary, National Research and Innovation Agency, Cibinong, West Java, Indonesia 16911. 6Directorate of Laboratory Management Research Facilities, Science and Technology Park, National Research and Innovation Agency, Cibinong, West Java, Indonesia 16911. Abstract Acacia honey (Accacia crassicarpa) contains various bioactive compounds, such as phenolics and flavonoids that provide pharmacological effects, including anticancer activity. This study aimed to determine the potential of acacia honey from Indonesia in inhibiting proliferation and inducing apoptosis in WiDr colon cancer cells in vitro. Cells were exposed to various concentrations of honey and analyzed using the MTT method to measure WiDr cell antiproliferation, Hoechst staining for apoptotic morphology, and qPCR for apoptotic gene expression against BAX, BCL- 2, CASPASE-3, CASPASE-8, and P53 genes. The results showed that acacia honey at a concentration of 5.5% could inhibit WiDr cell growth by 64.34%. The 5% acacia honey can increase the BAX/BCL-2 ratio, and reach the apoptosis execution stage by increasing CASPASE-3 expression. In addition, acacia honey induced apoptosis through extrinsic and intrinsic pathways at concentrations of 2.5% and 1.25%, as indicated by increased expression of CASPASE-8 and P53. The conclusion of this study is that acacia honey inhibits cell proliferation, triggers morphological changes, and increases apoptotic gene expression. Keywords: Indonesia Acacia honey, Antiproliferation, Apoptosis, qPCR, WiDr Cells Share Link | Plain Format | Corresponding Author (Yoggi Ramadhani Purwaningtyas)

24	Biochemistry	ABS-90
Bioactive Compounds and Biological Activity of Pontianak Orange Peel (Citrus reticulata) Extract Obtained by Supercritical Fluid Extraction: A Green Chemistry Approach for Sustainable Utilization of Agricultural Waste Shofi Indriyani1, Yulia Anita2*, Antonius Herry Cahyana1, Egi Agustian2, Megawati Megawati3, Tuti Wukirsari1* 1 Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok, 16424, Indonesia 2 Research Center for Molecular Chemistry, National Research and Innovation Agency (BRIN), Serpong, 15314, Indonesia 3 Research Center for Pharmaceutical Ingredients and Traditional Medicines, National Research and Innovation Agency (BRIN), Serpong, 15314, Indonesia Abstract Pontianak orange (Citrus reticulata) peel is an agricultural by-product rich in bioactive compounds with potential pharmaceutical applications. This study aimed to characterize the bioactive compounds and evaluate the biological activity of Pontianak orange peel extract obtained through Supercritical Fluid Extraction (SFE) as a green and sustainable extraction approach. Orange peels were dried, ground, and extracted using SFE. Chemical profiling was performed using GC-MS, while Total Phenolic Content (TPC) and Total Flavonoid Content (TFC) were determined using Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. Antioxidant activity was assessed via ABTS radical scavenging assay, and antibacterial activity was evaluated against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa using the disc diffusion method. The SFE process yielded 0.8% of extract. GC-MS analysis identified pentamethylflavone as the dominant compound with a peak area of 98.63%, while TFC values were 18.42 mg QE/g. Antioxidant activity showed an IC&#8325-&#8320- value of 0.17 mg/mL (ABTS). The extract exhibited stronger antibacterial activity against Gram-positive than Gram-negative bacteria, with the highest inhibition zone recorded against Bacillus subtilis at 14 mm. Pontianak orange peel extract obtained via SFE exhibited significant flavonoid content alongside promising antioxidant and antibacterial activities, supporting its potential as a natural bioactive source. The application of SFE as a solvent-minimizing green technology demonstrates a sustainable approach to agricultural waste valorization, contributing to eco-friendly development in the natural product industry. Keywords: Citrus reticulata, supercritical fluid extraction, green chemistry, pentamethylflavone, antioxidant, antibacterial, waste valorization Share Link | Plain Format | Corresponding Author (Shofi Indriyani)

25	Biochemistry	ABS-98
Selective Antimicrobial Profiling of Crocatin A from Piper crocatum: A Potential Therapeutic Modulator for Caries-Driven Oral Dysbiosismple Abstract Syifa Zahara Kultsum Azmi (a), Dikdik Kurnia (b), Toto Subroto (c) Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang 45363, Indonesia Abstract Conventional caries management relies on broad-spectrum antimicrobials that indiscriminately disrupt oral eubiosis. This study investigates the targeted modulatory potential of Piper crocatum isolates against the keystone cariogenic pathogen Streptococcus mutans, while preserving the commensal Streptococcus salivarius subsp. thermophilus. Bioassay-guided fractionation of the methanolic leaf extract yielded a major active metabolite, structurally elucidated via comprehensive spectroscopic dereplication (UV, FTIR, MS, 1D/2D NMR) as the neolignan Crocatin A. In vitro ecological selectivity was assessed via differential disk diffusion, while molecular mechanisms were evaluated using thermodynamic in silico docking against pathogenic (GtfB, SpaP) and commensal (GspB, SrpA) receptors. In vitro, Crocatin A exhibited a distinct pathogen-selective therapeutic trajectory (Ecological Selectivity Index, SI 1.4), significantly outperforming the non-selective clinical standard, chlorhexidine (SI 0.97). In silico analyses revealed this selectivity is governed by high-affinity, enthalpy-driven binding to the pathogenic biofilm-forming enzyme GtfB (deltaG 6.5 kcal/mol and Ki 17.2 mM), anchored by specific hydrogen bonds (ARG638, LYS289). Conversely, interactions with commensal surface receptors were predominantly entropy-driven and transient, yielding theoretical inhibition constants 5.4 to 8.9, fold higher (Ki 93.2 to 154.6 mM) than the pathogen target. Ultimately, Crocatin A functions as a precision microbiome modulator. By selectively neutralizing S. mutans virulence pathways while preserving commensal viability, it facilitates colonization resistance, offering a paradigm shift from total oral sterilization to targeted eubiotic restoration. Keywords: Crocatin A- Ecological selectivity- Glucosyltransferase B- Oral eubiosis- Piper crocatum Share Link | Plain Format | Corresponding Author (Syifa Z. K. Azmi)

26	Biochemistry	ABS-104
Antibacterial Test of Massage Oil made from VCO and Cymbopogon Nardus Oil with Varying Concentrations of Syzygium Aromaticum Essential Oil Sri Mulyani*, Dinda Ayu Ariyanti Sukma, Elfi Susanti VH, Sri Retno Dwi Ariani, Suryadi Budi Utomo, Widiastuti Agustina Eko Setyowati, Muhammad Hizbul Wathon Chemistry Education Study Program, Faculty of Teacher Training and Education, Sebelas Maret University Abstract Massage oil is often used in traditional medicine because it contains active ingredients with therapeutic effects, but there are few reports of massage oil with antibacterial activity. The purpose of this study was to make massage oil from VCO and lemongrass (Cymbopogon nardus) oil with varying concentrations of clove oil (Syzygium aromaticum) and test its antibacterial activity. The stages of research are as follows: (a) making Virgin Coconut Oil (VCO) using the fermentation method, (b) preparing essential oils of lemongrass and cloves, (c) making 3 formulas (F0, F1, and F2) of massage oil from VCO and lemongrass with variations in clove oil, and (d) testing the antibacterial activity of 3 massage oil formulas using the paper-disk diffusion method with test bacteria Staphylococcus aureus as gram-positive and Escherichia coli as gram-negative. The results showed that the greater the amount of clove oil added, the greater the massage oil^s antibacterial activity. Antibacterial activity against S. aureus is greater than against E. coli. Keywords: Massage oil, VCO, lemongrass oil, cloves oil, antibacterial. Share Link | Plain Format | Corresponding Author (Sri Mulyani)

27	Chemistry Education	ABS-18
ANALYSIS OF THE CHEMICAL REPRESENTATION ABILITY AT MACROSCOPIC, SUBMICROSCOPIC, AND SYMBOLIC LEVELS OF STUDENTS OF STATE SENIOR HIGH SCHOOL 4 TERNATE CITY ON ACID-BASE MATERIAL Julaina Lofonita, Indra Cipta, Ilham Sw Mauraji Pendidikan kimia, Universitas Khairun Ternate Abstract This research is motivated by the characteristics of chemistry that require the integration of three levels of representation, namely macroscopic, submicroscopic, and symbolic, which are often not mastered equally by students, especially in the abstract and conceptual acid-base material. This study is based on the theory of three levels of representation introduced by Johnstone, as well as the acid-base theories of Arrhenius, Bronsted Lowry, and Lewis as the conceptual basis of the material. The study aims to analyze the level of students^ chemical representation abilities and identify the tendency of dominance of certain levels of representation. The method used is descriptive quantitative with a cross-sectional design . The research subjects were 40 students of grade XII of SMA Negeri 4 Kota Ternate who were selected through purposive sampling. Data collection was carried out using a validated essay test consisting of 10 items, then analyzed using the ideal category descriptive technique. The results showed that representation abilities varied between levels and macroscopic was in the highest category compared to the submicroscopic and symbolic levels, with the symbolic level as the lowest achievement. This finding indicates that students find it easier to understand phenomena that can be observed directly compared to explanations at the particle and symbolic levels. Keywords: Please Just Try to Submit This Sample Abstract Share Link | Plain Format | Corresponding Author (Julaina Lofonita)

28	Chemistry Education	ABS-19
Design and Development of Brookhart HOTS-Based Assessment Instruments on Hydrocarbon Materials Using a Design and Development Research (DDR) Approach Nia Kurniawati, Yulia Sukmawardani, Ade Yeti Nuryantini UIN SGD Bandung Abstract The ability to design summative and formative assessment instruments, not only measures learning achievement but also measures in-depth understanding and trained skills are mandatory components that must be mastered by teachers. This study aims to design and develop Brookhart HOTS-based assessment instruments in hydrocarbon compound materials. This study uses the Design, and Development Research (DDR) approach, in designing and developing 13 Brookhart HOTS questions on hydrocarbon compound materials, with a one-person expert validity test stating that it is suitable for use, and validity, reliability, discriminating power, and difficulty level tests using the SPSS version 26 application. The results of the study showed that of the 13 questions developed, there were 11 questions that were suitable for use and valid based on the results of the validity test obtained a value range of 0.409-0.675 with a reference value of r table 0.349, then the calculated r value is greater than r table. The reliability test obtained by the Cronbach^s alpha value was 0.707 which means high reliability. The discriminatory power test was obtained from the Corrected Item-Total Correlation (CITC) value with an average of 0.59, which is included in the good category. The difficulty level test P was 0.92, which is included in the easy interpretation category. Keywords: Assessment Instrument, HOTS Brookhart, Hydrocarbon Compounds, DDR Share Link | Plain Format | Corresponding Author (Nia Kurniawati)

29	Chemistry Education	ABS-77
Exploring STEM-Project-Based Learning Through a Bungee Jumping Prototype Project: Implications for Students^ Scientific Literacy Wulan Permatasari, Rasna Solehayati, Sri Nur Koimah, Sumiyati Saadah, Yulia Sukmwardani, Ea Cahya Septia Mahen Master of Science Education Study Program, Postgraduate UIN Sunan Gunung Djati Bandung Abstract This study aims to describe the implementation of STEM-Project-Based Learning (STEM-PjBL) through a bungee jumping prototype project and to analyze its impact on students scientific literacy. A descriptive qualitative approach with a single case study design was employed involving eleventh-grade science students who participated in a series of STEM-PjBL learning stages: reflection, research, discovery, application, and communication. Data were collected through document analysis, classroom observations, and a scientific literacy questionnaire aligned with the PISA 2025 framework. The results show that the learning implementation achieved good to excellent levels across most stages, with the highest student engagement observed in the discovery and application phases. The bungee jumping project effectively supported students in understanding elasticity concepts through hands-on design, testing, and presentation activities. Scientific literacy outcomes indicated strong positive responses, particularly in applying scientific knowledge to practical and social contexts, although data interpretation and scientific investigation skills require further reinforcement. Overall, STEM-PjBL effectively enhanced students scientific literacy by providing meaningful, authentic, and collaborative learning experiences. Keywords: STEM-PjBL, scientific literacy, elasticity, bungee jumping, project-based learning Share Link | Plain Format | Corresponding Author (Yulia Sukmawardani)

30	Environmental Chemistry	ABS-15
Statistical Design and Green Extraction of Protein-Based Bio-Coagulant from Morinda citrifolia Seed for Sustainable Phosphate Removal Dian Arrisujaya Doctoral Study Program in Chemistry, Department of Chemistry, Universitas Indonesia, Depok 16424, Indonesia Abstract The transition toward sustainable chemical processes has stimulated increasing interest in biomass-derived functional materials for environmental remediation. This study presents a green chemistry approach for developing a protein-based bio-coagulant from Morinda citrifolia seed via salt-assisted extraction aimed at enhancing chemically active biomolecules involved in pollutant binding. The material was applied for phosphate removal as a representative case of nutrient contamination in aquatic systems. Functional group analysis using Fourier Transform Infrared spectroscopy indicated enrichment of amide and hydroxyl groups associated with proteinaceous compounds that promote adsorption and coagulation interactions. To achieve systematic process understanding, Response Surface Methodology employing a Box-Behnken Design was implemented to evaluate the combined effects of pH, coagulant dosage, and initial phosphate concentration on removal efficiency and adsorption capacity. Statistical modelling demonstrated strong agreement between predicted and experimental responses, identifying coagulant dosage as the most influential parameter controlling phosphate removal performance. Optimised conditions enabled removal efficiencies above 90% under near-neutral pH, indicating chemical stability and practical applicability without extensive pH adjustment. The removal behaviour is attributed to synergistic adsorption-coagulation mechanisms driven by electrostatic interaction between anionic phosphate species and positively charged biomolecular sites. This work highlights the integration of green extraction, statistical optimisation, and natural material chemistry as an effective framework for sustainable water treatment and chemistry education innovation. Keywords: green chemistry, response surface methodology, bio-coagulant, sustainable materials, phosphate remediation Share Link | Plain Format | Corresponding Author (Dian Arrisujaya)

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