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Riboflavin is an intrinsic component of significant nutritional and growth factors of living organisms. It was fermentatively synthesized from different microorganisms such as Ashbya gossypii, Eremothecium ashbyii, Candida famata, and Bacillus subtilis. This water-soluble vitamin is a part of commercial interest since, the earliest decade when human health was in threat. Despite its multiple utilities in all market sectors, the global riboflavin market is seeming to increase its demand, annually. To that, findings affecting to various environmental and nutritional factors contributing to riboflavin yield were improvised with a cost-effective statistical experimental design. Previously, the individual effect of components on riboflavin production was evaluated via One-Factor-at-a-Time (OFAT) method. Using recombinant Ashbya gossypii strain, the combined effects of six variables (sunflower oil, corn steep liquor, yeast extract, glycine, potassium phosphate, and Tween 60) were assessed in Plackett-Burman Design. A total of five statistically significant (P<0.05) factors - sunflower oil, Tween 60, corn steep liquor, glycine, and potassium phosphate (KH2PO4) were identified. The statistical analysis proposed that the linear mathematical model used for prediction is significant with the coefficient of determination R2(0.9025). Comparatively to the original medium composition, 49% of higher metabolite was achieved based on the model of the optimized medium. [ABSTRACT FROM AUTHOR]

Fermentation is one of the most crucial steps to improving the quality of cocoa beans. The majority of farmers in Indonesia do not ferment cocoa beans in its production, hence the beans produced are dried, unfermented cocoa beans. To improve the quality of dried cocoa beans, re-fermentation of cocoa beans can be done. During fermentation, microorganisms are involved, and one of the microorganisms known to be beneficial for cocoa bean fermentation is yeast. This study aimed to determine the effect of the yeast consortium addition on the chemical properties of the dried cocoa bean during fermentation. Fermentation was carried out for 48 hours in a styrofoam box by soaking the beans into the media of cocoa peel extract and yeast extract with the addition of five inoculum combinations, namely ABC, ABD, ACD, BCD, ABCD, from 4 yeast isolates P. kudriavzevii(A), P. scutulata (B), P. cecembensis(C), and S. cerevisiae(D). Temperature, pH, total polyphenols, antioxidant activity, reducing sugars, and fermentation index were evaluated during fermentation. Based on the research results, the temperature in all treatments remained at an average of 32-33.6°C, and the pH value constantly increased in the combination of ABD and ABCD with pH values of 6 and 7. The variety of ABD obtained the highest total polyphenol content at 23.18 mg/g. ABD treatment experienced the highest increase in reducing sugar (6.7 mg/g). The lowest antioxidant activity was obtained by the combination of ABCD (0.51%). The fermentation index (FI) of all treatments has increased, with ABC treatment having the highest FI value of 1.13. [ABSTRACT FROM AUTHOR]

Fermentation is a biochemical process that requires various microorganisms. The activity of microorganisms in the cocoa bean fermentation process is important to the success of enzymatic molecule breakdown. Yeast is a functional microorganism involved in cocoa bean fermentation, functioning as a glucose and ethanol producer, amongst many other things. Beyond its primary role in sugar breakdown, yeast has a wide range of other abilities. One of these is its ability to produce cellulase and protease enzymes, which are both frequently used in industry. The objective of this study was to discover yeast isolates that can degrade cellulose and proteases from the fermentation of Sulawesi 1 and TSH 858 cocoa beans. The study was carried out in January 2022 at the Laboratory of Microbiology, FMIPA UNJ. The method used is descriptive. Data were obtained by isolating up to 20 g of sample from each fermentation. The results showed 231 yeast isolates, including 136 from Sulawesi 1 and 95 from TSH 858. The cellulolytic screening revealed 29 isolates from Sulawesi 1 and 27 isolates from TSH 858, whereas the proteolytic screening discovered three isolates and no isolate from TSH 858 that produced proteolytic enzymes. [ABSTRACT FROM AUTHOR]

Over the last two decades, there is an increasing demand for polysaccharide-producing microbes in various fields of industries such as food, pharmaceutical, and also for bioremediation. However, research on the exopolysaccharide produced by Lactobacillus acidophilus is still limited and the optimization production process of exopolysaccharides does not include a large range of chemical materials. Therefore, this study aimed to optimize the cultivation medium of Lactobacillus acidophilus for high exopolysaccharide production via submerged fermentation. At first, various carbon sources such as xylose, lactose, maltose, fructose, sucrose and glucose were screened using shake flasks. The best carbon source found was lactose with the highest exopolysaccharide production of 2.43 g/L. Next, the experiment was continued by examining the influence of various nitrogen sources, including yeast extract, beef extract, and peptone. The results demonstrated that peptone was the most effective nitrogen source, producing the highest exopolysaccharide amount of 3.25 g/L. In conclusion, it was discovered that Lactobacillus acidophilus in submerged fermentation produced the highest amounts of exopolysaccharides when provided with lactose and peptone as carbon and nitrogen sources, respectively. [ABSTRACT FROM AUTHOR]

Gram-negative bacteria that cause food poisoning became an important focus of attention in both developed and developing countries. These bacteria include Salmonella spp and Escherichia coli. In the previous stage, the conditions and reaction formula for the prototype rapid kit detections of foodborne pathogens were obtained using the Real Time PCR method. This research is a stage of validating the conditions and reaction formulas found in the previous stage, to obtain a consistent and reproducible prototype product. Validation of the isolation stage of Salmonella spp (Salmonella typhi, Salmonella typhimurium, Salmonella enteritidis) and Escherichia coli bacteria were carried out by cultivating cultures at 250 rpm aeration conditions, and temperature 37oC. A total of three mL of cultures was centrifuged at 5000 rpm and yielded each cell weight of 0.25-0.6 grams. The results of the isolation of genomic DNA with Qiaprep were 200 microliters with the amount of DNA 10600-11700 nanograms. The concentrations were 23-58.5 ng/mL, and the purities were 1.809-2.084. Furthermore, the resulting genomic DNA is used as a template for the PCR process. The validation of the PCR stage of Salmonella spp using annealing temperature of 60oC and template concentration of 50 ng resulted in the Salmonella typhi fim-C gene amplicons, Salmonella typhimurium pef gene and Salmonella enteritidis prot6E gene measuring 95 bp, 139 bp and 170 bp, respectively. PCR validation of the E. coli DNA template at 60oC with the same concentration resulted in an amplicon measuring 121 bp. Based on the data obtained, it can be concluded that the validation of the isolation stage and confirmed PCR produced data that were consistent with previous studies and were reproducible. With the result that the development of a detection kit prototype can be continued to the validation stage with Real Time PCR and laboratory-scale trials for artificially contaminated food samples and food samples from products on the market. [ABSTRACT FROM AUTHOR]

The case of foodborne disease by pathogenic bacteria is an extraordinary event whose source and route of spread occur quickly. Bacillus cereus and Listeria monocytogenes are included in the gram-positive bacteria that cause food poisoning infections in humans. In previous studies, the conditions and reaction formulas for the prototype rapid kit detections of foodborne pathogens were obtained using the Real-Time PCR method. This research validates the conditions and reaction formulas in the prior stage to obtain a consistent and reproducible prototype product. Validation of the isolation stage of Bacillus cereus and Listeria monocytogenes bacteria was carried out by culturing bacterial cultures at aeration conditions of 250 rpm and a temperature of 37oC. A total of three mL of the culture was centrifuged at 5000 rpm and yielded 0.03 and 0.02 grams of B. cereus and L. monocytogenes cells, respectively. The results of the isolation of genomic DNA with Qiaprep were 200 µL with the amount of DNA 10600-11700 nanograms; the concentration was 23-58.5 ng/μL, and the purity was 1.809-2.084. Furthermore, the resulting it is used as a template for the PCR process. The validation of the PCR stage of B. cereus and L. monocytogenes at a temperature of 60oC and template concentration of 50-60 ng resulted in an amplicon of both bacteria. The cyt-k gene B. cereus and hly L. monocytogenes are measuring respectively 114 bp and 158 bp. Based on the data obtained, it can be concluded that the validation of the isolation and PCR stages has been successfully carried out by producing data consistent with previous studies. The development of a detection kit prototype is then revealed to the Real-Time PCR stage and laboratory-scale trials for artificially contaminated food samples and food samples from products on the market. [ABSTRACT FROM AUTHOR]