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Simple Summary: Naw Mai Dong is an ethnic fermented bamboo shoot product that is popular in the upper northern region of Thailand. Xylan is a component of hemicellulose that can be found in bamboo shoots. It is a raw material utilized in xylooligosaccharide production. To produce Naw Mai Dong, bamboo shoots are sliced and pickled in bottles or jars that contain water rinsed from rice crops with or without salt. This would differ from the simple brine comprised of water and salt that is associated with most other pickled products. Naw Mai Dong is sour due to its acidity. Importantly, fermented fruits and vegetables are a potential source of lactic acid bacteria, which have been well-documented to possess a number of probiotic characteristics. This would imply that some of the lactic acid bacteria present during bamboo shoot fermentation could serve as efficient xylooligosaccharides-fermenting probiotic lactic acid bacteria. Xylooligosaccharides (XOSs) are produced from xylan, which is a component of the hemicellulose that can be found in bamboo shoots. Naw Mai Dong, an ethnic pickled bamboo shoot product of northern Thailand, is generally characterized as acidic and has a sour taste. It can be considered a potential source of probiotic lactic acid bacteria (LAB). This study aimed to isolate efficient XOSs-fermenting probiotic LAB from ethnic pickled bamboo shoot products. A total of 51 XOSs-fermenting LAB were recovered from 24 samples of Naw Mai Dong, while 17 strains exhibited luxuriant growth in xylose and XOSs. Among these, seven strains belonging to Levicaseibacillus brevis and Pediococcus acidilactici exhibited similar growth in glucose, xylose, and XOSs, while the rest showed a weaker degree of growth in xylose and XOSs than glucose. Sixteen strains exhibited resistance under gastrointestinal tract conditions and displayed antimicrobial activity against foodborne pathogens. Notably, Lv. brevis FS2.1 possessed the greatest probiotic properties, with the highest %hydrophobicity index and %auto-aggregation. Effective degradation and utilization of XOSs by probiotic strains are dependent upon xylanase and β-xylosidase production, as well as xylose metabolism. It can be concluded that pickled bamboo shoot products can be a beneficial source of XOSs-fermenting probiotic LAB. [ABSTRACT FROM AUTHOR]

Biohydrogen is one of the most potential alternative fuels for the future. Among various substances from agricultural factory waste, molasses and wastewater from ethanol distillation plants are the main focus of this study. To overcome the limitation of bio-H 2 production, the direct screening of waste substrates for an efficient producer using co-culture free technique is an interesting choice. Competent species with H 2 -producing ability and valuable volatile acid such as acetic acid were selected. Several bacteria were isolated and had their species identified by microbial 16SrDNA sequence analysis and phylogenetic analysis by Maximum Likelihood method. Bacillus coaglulans , B. circulans , Sporolactobacillus inulinus , Lactobacillus spp., Pediococcus acidilactici , Paenibacillus thermophilus , Chronobacter sakazaki and Clostridium beijerinckii were found in both reducing-sugar rich waste and wastewater. For bio-H 2 application in this criteria, potent natural hydrogen producer B. coagulans MO11 and C. beijerinckii CN were picked to test the growth ability on different substrates (carbon-dioxide, l -arabinose, d -xylose, d -glucose, d -fructose, sucrose, maltose, cellobiose, starch and others). Wastewater from sugarcane factories and other agricultural factories in Thailand were tested for physical and biochemical characteristics which would make them suitable renewable substrates. Among all, Bacillus coagulans MO11 could produce hydrogen gas using molasses and ethanol refinery wastewater effectively (1.634 mol H2 /mol hexose) as detected by Drager tube, which was the maximum yield in this study. In comparison, the experiment performed by using B. coagulans MO11 and C. beijerinckii CN fed with 40X diluted molasses wastewater showed better production of H 2 gas in Clostridium beijerinckii CN during the final 72-hr gas collection (79 mL/L and 125 mL/L respectively). The results pointed in the same direction when replacing 40X diluted molasses with 5X diluted refinery wastewater supplemented with trace elements. • New isolates of hydrogen-producing bacteria from wastewater. • Application of molasses and ethanol refinery wastewater for H 2 production. • Hydrogenase gene observation in hydrogen-producing potential isolates. [ABSTRACT FROM AUTHOR]

Abstract: Acid-sensitive mutants of Pediococcus acidilactici BCC 9545, a starter culture of the Thai fermented pork sausage nham, were isolated as spontaneous neomycin resistant mutants. The mutants generally produced less acid and acidified the culture media less than the parent strain in a 72h culturing period. Interestingly, the ATPase activities of the mutants did not differ considerably from that of the parent strain in acidic conditions. It was also found that the internal pH values of the mutant strains were somewhat lower in neutral environment, while at pH 5.0 their internal pHs were significantly lower compared to the parent''s. Inhibiting the H+-ATPase activities in energized cells by N,N′-dicyclohexyl carbodiimide also revealed that protons were leaking from the mutants at neutral pH, which increased under acidic conditions. In contrast, the parent strain exhibited a smaller proton leak and only under acidic conditions. The membrane fatty acid analysis of the mutants indicated that under acidic conditions the mutants had a significantly smaller major unsaturated/saturated fatty acids ratio ((C18:1 +C18:3n6)/(C16:0 +C18:0)) compared to the parent strain''s membrane. Taken together, these observations suggest there is a reasonable possibility that the membrane fatty acid profile differences in the mutants resulted in their acid-sensitivity. [Copyright &y& Elsevier]