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Tannin-rich compounds are widely produced as by-products of many agro-industrial processes. Tannase is an attractive hydrolase for the bioconversion of tannin-rich materials into value-added products by accelerating the hydrolysis of ester and depside linkages. It has opened new opportunities in several industrial sectors, such as food, drinks, and medicines. Primary sources of tannase are microorganisms, particularly bacteria. Tannases or tannin acyl hydrolases, are an important group of biotechnologically relevant enzymes in several industrial applications. Microbial tannases are mostly induced extracellular enzymes produced by submerged and solid-state fermentation. Tannins containing low-value agro-industrial wastes are being extensively used in industries. This review provides a more in-depth knowledge of the research related to the biochemical characteristics of the tannase enzyme activity (in terms of molecular weight, the effect of pH, the effect of temperature, the effect of metal ions, inhibitor, and chelator), extraction, and purification methods. Additionally, the potential use of agricultural waste as a substrate for tannase production has also been reviewed, including the utilization of pomegranate peel waste (PmPW), banana peel waste (BPW), or potato peel waste (PtPW).

Lactic acid bacteria (LAB) have been extensively explored as potential biopreservants. They could produce substances with antimicrobial properties such as bacteriocins and organic acids which can also be the cause of antagonistic activity shown by LAB. Thus, the objective of this study is to assess the antagonistic activity of LAB isolated from fermented Oreochromis niloticus against foodborne pathogens and to determine the potential of LAB as a surface decontaminant of raw chicken breast and Tilapia fish fillet. The antagonistic activity of LAB has been shown to affect Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus. When LAB was introduced to the mixed cultures of E. coli, S. typhimurium, and S. aureus, the growth of those pathogens drastically reduced and this has proven that LAB grows stronger and more stable while eliminating the pathogens. LAB and their cell-free supernatant (CFS) were also introduced into the raw chicken breast and fresh Tilapia fish fillet, where E. coli growth was recorded. Both cell cultures and CFS of LAB showed inhibition of E. coli on chicken breast and Tilapia fish fillet in the range of 0.16 to 1.28 log10 reduction and 0.12 to 1.12 log10 reduction, respectively. In conclusion, the results above suggest that LAB isolated from fermented O. niloticus has the potential to be a surface decontaminant. Additionally, both LAB and their CFS can also be used as biopreservative for both chicken breast and fish fillet due to a very good antagonistic activity shown by the LAB toward the foodborne pathogens.

Vinegar is a condiment made from various sugary and starchy materials by alcoholic and subsequent acetic fermentation. Vinegar can be produced via different methods and from various types of raw material. A new alternative substrate for vinegar production namely mature coconut water has been tested and was compared with 2 common substrates which were coconut sap and pineapple juice. Substrates such as sap and juices have been found to have high amount of total soluble solids which corresponding to high sugar content in the substrates which is more than 14oBrix. Therefore, both substrates could be directly used for vinegar production without requirement of other carbon sources. However, coconut water which showed low Brix value need to be adjusted to 14oBrix by adding sucrose prior to the fermentation process. Substrates fermented with Saccharomyces cerevisiae have yielded 7-8% of alcohol within 7-10 days aerobic incubation at room temperature. The alcoholic medium were then used as a seed broth for acetic fermentation with Acetobactor aceti as inoculums and fermented for approximately 2 months to obtain at least 4% of acetic acid. Investigation on the effect of inoculum sizes and implementation of back-slopping technique were performed to improve the processing method for coconut water vinegar production. The results show that 10% of inoculum size was the best for acetic acid fermentation and the back-slopping technique has helped to reduce the process time of coconut water vinegar production.

This study aims to determine the effect of emotional intelligence, sociodemographic factors on investment decisions, and financial literacy as moderating variables of emotional intelligence and sociodemographic factors on investment decisions. The research population is investor saham pemula (ISP) community, a sample of 106 investors. The analysis technique used in this research uses the help of the Smart PLS 3.0 data processing application. the results of the study indicate that Emotional Intelligence has a positive and significant effect on investment decisions; Sociodemography has no effect on investment decisions; Emotional intelligence is positive and significant to investment decisions moderated by financial literacy; positive and significant sociodemography on investment decisions moderated by financial literacy