This study aims to develop and characterize a nano-fertilizer for foliar application on rock melon (Cucumis melo). The formulation of the nano-fertilizer was based on a ternary phase diagram, which showed the behavior of NPKTE within emulsion components made up of surfactants, oil, and water, with the isotropic region identified as the most stable. In addition, the formulation was prepared using a high-energy emulsification method, consisting of 25.04% Tween 80, 4.36% neem oil, 20.60% water, and 50% NPK-TE. The results showed that the optimized nano-emulsion had a particle size of 92.58 nm, with a polydispersity index of 0.156, a zeta potential of -39.8 mV, a surface tension of 40.67 m -1 , and a viscosity of 100.46 mPa s -1 . Morphological analysis of the optimized nano-fertilizer showed spherical particles, showing good stability. The formulation showed no phase separation during the centrifugation test and maintained stability at 3 different temperatures (4, 25, and 54 °C) with turbidity reduction values of 23.18%, 8.65%, and 42.90%, respectively, over a period of 60 days.

This research aimed to investigate the potential of lemongrass (Cymbopogon citratus) leaf agricultural by-products as a source of essential oil, and evaluate the antioxidant and antibacterial activities. In this context, the material used was subjected to microwave pre-treatment to enhance the yield. Lemongrass leaf was often discarded as an agricultural by-product. The utilization was examined through different drying methods, including fresh, wilted, and dried treatments. Lemongrass leaf was also treated with microwave (+MV) and non-microwave (-MV) pre-treatments. The essential oils were analysed for physicochemical properties. The chemical composition was determined through gas chromatography-mass spectrometry (GC-MS), and the tissue microstructure was observed by SEM. Antioxidant activity was measured with the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, while MIC and MBC values were assessed using the microdilution method. The results showed that the distillation of dried leaf with microwave pre-treatment provided the highest oil yield of 0.20%. SEM analysis showed that drying and microwave pre-treatment altered the leaf microstructure, enhanced glandular trichomes, and improved extraction efficiency. The physicochemical properties included a bright yellow colour, a fresh citrus aroma, a specific gravity of 0.971 g/mL, a refractive index of 1.486, and a solubility ratio of 1:3 in alcohol. The main components were citral (geranial (44.07–46.81%), neral (35.64 – 36.60%)), geranyl acetate (2.03–5.66%), isogeranial (1.61–2.57%), isoneral (0.96–1.76%), β-pinene (0.16–3.63%). Lemongrass leaf oil exhibited strong antioxidant activity with an IC50 of 61.65 to 84.5 µg/mL, antibacterial activity against E. coli and S. aureus with MIC of 0.3–1.3% and 0.3–1.8%, as well as an identical MBC value of 0.5–2% for both bacteria. This research showed that essential oil extraction increased the value of lemongrass leaf by-products.

In Indonesia, the majority of coffee production consists of Robusta which is predominantly sold as green beans. However, traditional processing methods without fermentation often lead to inconsistent quality. Therefore, this study aims to enhance Robusta green coffee bean quality and consistency by conducting fermentation using the lactic acid bacteria Enterococcus faecium and the yeast Pichia fermentans as starter cultures. Fermentation was conducted for 5 days at 30 °C, then every 24 hours, coffee beans were sampled for pH analysis, total yeast, and lactic acid bacteria count. Before and after fermentation, coffee bean samples were analysed for reducing sugar content using the DNS method, as well as chlorogenic acid and amino acid content using HPLC. Sensory analysis was conducted after fermentation. The results showed that after five days of fermentation, a decrease in pH was observed in all treatments. The application of the starter culture consisting of Pichia fermentans accelerated the growth of the total yeast population, while the addition of Enterococcus faecium enhanced the total lactic acid bacteria population. Fermentation caused a reduction in the reducing sugar content of all treatments. However, a significant rise in chlorogenic acid content was found in the treatment using Pichia fermentans, the combined treatment of Pichia fermentans and Enterococcus faecium, as well as in the control. The highest amino acid content after fermentation was generally obtained using the Pichia fermentans single-starter treatment, with the highest alanine, arginine, aspartic acid, leucine, glutamic acid, isoleucine, phenylalanine, valine, threonine, and tyrosine content. The treatment also produced the highest final cupping score of 81.65, classifying the sample as Fine Robusta coffee. This suggests that Pichia fermentans has the most beneficial effect on coffee quality. The cupping scores of brewed coffee treatment above 80 also suggest that Enterococcus faecium has the potential to improve coffee quality

Over-fermented tempeh is traditional ingredient in Indonesian dishes, serving as a seasoning due to the unique flavor. Therefore, this study aimed to evaluate the effect of different fermentation periods, packaging types, and blanching processes on flavor of over-fermented tempeh powder. The results showed that tempeh amino acid composition increased with a prolonged fermentation period. However, the type of packaging and blanching process did not significantly affect these parameters. Changes in the concentration of chemical composition, such as amino acids and sugar, affected the sensory perception. Longer fermentation period was found to increase the amounts of amino acids contributing to umami and bitter tastes, while sugar content decreased with extended fermentation and in samples subjected to blanching. Nucleotide composition umami taste was more pronounced in plastic samples and those not subjected to blanching. Sensory evaluation also showed variations in the intensity of umami, bitter, sour, sweet tastes, and pungent, woody, floury, and rancid flavor. Based on the results, optimal fermentation period for producing over-fermented tempeh powder was approximately seven days, where the compositions of sugars, amino acids, and nucleotides remained relatively high. After complete fermentation, the concentration of bitter amino acids was excessively high and remained acceptable to consumers. These results showed the effect of fermentation period on flavor profile of over-fermented tempeh powder, providing valuable insights for application in food product development.

This study used modified fly ash as a material to adsorb free fatty acid in Crude Palm Oil. One or two types of modification treatments in previous studies were used to investigate the effect on the absorption process. Therefore, this study focused on the capacity of the modified fly ash in adsorbing FFA with varying concentrations and durations of adsorption. Modification of fly ash began through leaching process using hydrochloric acid (HCl), followed by activation using hydrogen peroxide (H₂O₂), and reactivation using cocamidopropyl betaine (CAPB) surfactant. Scanning Electron Microscope Energy Dispersive X-Ray (SEM-EDX) is used to analyze the morphology and elements, while a Gas Sorption Analyzer (GSA) is used to analyze the pore radius, surface area, and pore volume of modified fly ash. Based on SEM-EDX result, fly ash had an amorphous shape with silicon (32.15%) and oxygen (50.29%) as the major elements. While GSA showed that the surface area, total pore volume, and average pore diameter were 15.34 m²/g, 0.02 cc/g, and 3.23 nm, respectively. Furthermore, modified fly ash had adsorption efficiency and capacity of 44.38%±0.21 and 140 mg/g±0.21, respectively. Then, adsorbent mass of 6% w/w and adsorption duration of 60 minutes recorded as the optimal condition of FFA adsorption process using fly ash. The maximum permissible FFA in cooking oil based on Standar Nasional Indonesia (2019) was 0.30%. Because of that, multi-stage adsorption was carried out to reduce the FFA in order to comply with Standar Nasional Indonesia (2019). The adsorption with twice repetition can produce CPO with FFA < 0.30% (initial FFA content of 1.2%). Due to the reduction level of FFA, the yield of the CPO obtained from each step was ±60-80%. This study could be applied in industry to reduce the FFA content and enhance the CPO quality.

Fructose solubility is one of the major challenges inhibiting enzymatic synthesis of fatty acid sugar ester. Therefore, this study aims to define the optimal parameters for manufacturing fructose oleic ester (FOE) utilizing a supersaturated fructose solution coupled with ultrasound technology. Factors such as esterification time, ultrasound power, and substrate flow rate were evaluated. The reaction was carried out by adding the supersaturated fructose solution and oleic acid to the immobilized lipase in the jacketed fluidized bed reactor equipped with an ultrasound. FOE was evaluated based on ester concentration, ester bond, and emulsification properties. The results showed thatesterification activity of lipase was 36.45±9.95 U/g matrix. Fructose concentration in the supersaturated fructose solution was 12.30±2.33 mg/mL. The optimal parameters for synthesizing FOE were defined at 180 Watt and 0.2 mL/min for 180 min of reaction after one time using a series of esterification apparatus. FOE concentration was 85.13±9.56% and the sample with the best conditions had Rf value of 0.2 to ~0.8, wave absorption band for ester group (C=O) at wavenumber ~1712 cm -1 with a new peak (C-O bond) at 1373 cm -1 , emulsion capacity 99.86±0.01%, emulsion stability of 99.29±0.04%, and droplet size of 1.00 µm with non-uniform droplet size distribution (polydispersity index (PDI)=1.00).

γ-Aminobutyric acid (GABA) is a major inhibitory neurotransmitter with beneficial effects on human health. Therefore, this study aimed to isolate lactic acid bacteria (LAB) from seredele, a Balinese fermented soybean, with GABA-producing potential. 16S rRNA sequencing was used to assess bacterial communities in seredele, with Providencia, Enterococcus, Vagococcus, and Bacillus identified as the predominant genera. The results showed that strains S11B and S211K produced the highest GABA levels and were identified as Limosilactobacillus fermentum and Enterococcus faecium, respectively. E. faecium S211K had maximum GABA production at 24 hours of cultivation, while L. fermentum S11B had maximal production at 48 hours. Both strains remained viable for up to 120 hours of cultivation. In conclusion, seredele serves as a source for isolating GABA-producing LAB, emphasizing the significance of local LAB with functional properties.

Kaffir lime leaves (Citrus hystrix D.C.) contain various bioactive compounds, including phenols, terpenoids, alkaloids, and flavonoids. These bioactive constituents are highly susceptible to degradation. Therefore, encapsulation is necessary to enhance their stability. The use of maltodextrin as the sole coating material often results in particle agglomeration and weak microcapsule structures. This research evaluated how the ratios and concentrations of coating materials affect the physicochemical properties of kaffir lime powder. This research involved the preparation of starch using the photooxidation method, the extraction of kaffir lime leaves, the production of kaffir lime leaves powder, and the analysis of kaffir lime leaves powder. The parameters evaluated included moisture content, hygroscopicity, solubility, and Fourier Transform Infrared (FTIR). Data were analyzed using the Analysis of Variance (ANOVA) test with a significance level of ≤ 0.05. The results showed that the combination of photooxidized starch and maltodextrin as an encapsulation material, at a total concentration of 60% had a moisture content of 9.18%, hygroscopicity 5.71%, solubility 61.91%, polyphenol content 5.33 mg GAE/g, and polyphenol damage 10,06%.

Probiotics are health-beneficial microorganisms found in the human digestive tract, and Aloe vera (Aloe vera var. chinensis (L.) Baker) is potentially a source of prebiotics that support the growth of probiotics. Therefore, this research aims to analyze the effect of Aloe vera juice on Lactobacillus rhamnosus ATCC 9595 growth, total lactic acid, total reducing sugars, antioxidant activity, total Short Chain Fatty Acid (SCFA), and metabolite profile. Four experimental groups of Aloe vera concentration were used (0%, 25%, 50%, and 75%), each with three different incubation times (0, 24, and 48 hours). Bacterial growth was analyzed using Total Plate Count and pH measurement, while total lactic acid, total reducing sugars, and antioxidant activity were analysed by titration, 3,5-dinitrosalicylic acid (DNS) technique, and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) test, respectively. SCFA was measured using Gas Chromatography-Mass Spectroscopy (GC-MS), and substances potentially associated with probiotic metabolic activities were identified using targeted Ultra High-Performance Liquid Chromatography (UHPLC)-High-Resolution Mass Spectrometry (HRMS). The results showed that after 48 h, Aloe vera juice with a concentration of 50% (v/v) significantly increased bacterial colonies by 85.49% and antioxidant activity by 36.13%, 75% (v/v) significantly decreased pH by 24.67%, and 25% (v/v) significantly increased total lactic acid. Acetic acid was detected during SCFA assessment, with the highest concentration found in the group of 25% Aloe vera. Targeted UHPLC-HRMS analysis identified aloe emodin, butyric acid, lactic acid, citric acid, and hydroxy aloin in the fermented Aloe vera juice. The highest metabolite content was citric acid (area max 2.95x10 9 ), a tricarboxylic acid, and all experimental groups had no significant effect on lowering total reducing sugars. These results present the promising prospects of Aloe vera juice as a natural resource for prebiotics to thrive and generate beneficial metabolites with antioxidant properties through metabolic processes.

This study aims to optimize the fermentation conditions of Bacillus sp.01 for the simultaneous production of cellulase and reducing sugars from oil palm empty fruit bunch (OPEFB). Milled OPEFB was used as the sole carbohydrate source in a mineral salt medium to investigate the effects of temperature (30-45 °C), pH (5.0-8.0), and nitrogen sources on the fermentation performance of Bacillus sp.01. The results showed that the highest sugar and cellulase production were achieved at pH 7.0 and 35 °C, yielding 2.52 mg/mL and 0.93 U/mL, respectively, in a 100 mL batch system enriched with 1% milled OPEFB. Regression analysis showed that the optimum sugar and cellulase production conditions were pH 6.73 and 32.5°C. Organic nitrogen sources (beef extract and peptone) showed better performance in promoting sugar and cellulase production than inorganic nitrogen sources (NH4 NO3 and (NH4 )2 SO4 ). These results show the potential of using OPEFB as a substrate for bioconversion by Bacillus sp.01, which could contribute to developing sustainable waste management strategies in the palm oil industry.