Endang S. Rahayu

Diversity in gut bacterial community of school-age children in Asia

Asia differs substantially among and within its regions populated by diverse ethnic groups, which maintain their own respective cultures and dietary habits. To address the diversity in their gut microbiota, we characterized the bacterial community in fecal samples obtained from 303 school-age children living in urban or rural regions in five countries spanning temperate and tropical areas of Asia. The microbiota profiled for the 303 subjects were classified into two enterotype-like clusters, each driven by Prevotella (P-type) or Bifidobacterium/Bacteroides (BB-type), respectively. Majority in China, Japan and Taiwan harbored BB-type, whereas those from Indonesia and Khon Kaen in Thailand mainly harbored P-type. The P-type microbiota was characterized by a more conserved bacterial community sharing a greater number of type-specific phylotypes. Predictive metagenomics suggests higher and lower activity of carbohydrate digestion and bile acid biosynthesis, respectively, in P-type subjects, reflecting their high intake of diets rich in resistant starch. Random-forest analysis classified their fecal species community as mirroring location of resident country, suggesting eco-geographical factors shaping gut microbiota. In particular, children living in Japan harbored a less diversified microbiota with high abundance of Bifidobacterium and less number of potentially pathogenic bacteria, which may reflect their living environment and unique diet.

YCM1008A, a Novel Ca2+-Signaling Inhibitor, Produced by Fusarium sp. YCM1008

In the course of screening for drugs that suppress the Ca2+-mediated growth inhibition in a yeast mutant, we found that the metabolite of Fusarium sp. strain YCM1008 inhibited Ca2+-signaling. A novel pyrano-pyridone, YCM1008A was isolated from the fermentation broth using HLB column chromatography followed by HPLC, and the structure was elucidated by spectral analysis. YCM1008A suppressed Ca2+-induced growth inhibition of the Saccharomyces cerevisiae (Δzds1Δsyr1) mutant.

Conformational significance of EH21A1-A4, phenolic derivatives of geldanamycin, for Hsp90 inhibitory activity.

Hsp90 is an attractive chemotherapeutic target because it is essential to maturation of multiple oncogenes. We describe the conformational significance of EH21A1-A4, phenolic derivatives of geldanamycin isolated from Streptomyces sp. Their native free structures are similar to the active form of geldanamycin bound to Hsp90 protein. Their conformational character is a probable reason for their high-affinity binding. Lack of toxic benzoquinone in EH21A1-A4 also adds to their potential as lead compounds for anti-tumor drugs.

Chemical characteristic of salt fermented meat inoculated with Pediococcus ssp

The research goal is knowing of the characteristict of salt fermented meat by Pediococcus ssp. There were microbiological, chemical, and off-flavor compound during fermentation. This study was conducted on research of influence of salt-meat fermentation inoculated used starter. They were included microbiological characteristics, and chemical characteristics. Microbiological characteristics observed were total bacteria, number of coliform groups, bacteria producing bioamine, and total lactic acid bacteria. The result showed that decreasing of coliform and bioamine producer bacteria, and total lactic acid bacteria decreased 3 log cycle. While the soluble protein increased of 7-8% and bioamine increased of 5-6 mg/100 g. And then Off-flavour compound, TVN and TMA increased of 36-20 mg/100g and 16-30 mg/100g, respectively. Conclusion of the research that Pedioccoccus ssp. influenced salt fermented meat.

Effect of heat adaptation and pH adjustment on the survival of spray-dried Lactobacillus paracasei SNP2

Purpose The purpose of this paper is to study the effect of heat adaptation, pH adjustment, and the combination pretreatments to the resistance of Lactobacillus paracasei SNP2 in heat shock and spray drying. Design/methodology/approach Sub-lethal and lethal temperature range of L. paracasei SNP2 was determined by enumeration of cell survival after incubation at 37-55°C for 30 min. A certain temperature from sub-lethal range was selected for heat adaptation. Heat adaptation (H), pH adjustment (pH), and combination of pretreatments (pH-H) were applied prior to heat shock and spray drying. Findings The selected condition for heat adaptation and heat shock is 44°C, 30 min and 55°C, 15 min, respectively, based on the sub-lethal and lethal temperature range. By heat shock, cells in the whey-sucrose medium showed cell death of 2.05 log cycles, lower than cell death in the MRS medium of 4.84 log cycles. The pretreatments showed slight increase of heat resistance in cell grown in whey sucrose. The effect of H, pH, and pH-H pretreatments highly increase heat resistance of cell grown in MRS indicated by cell death of 4.27, 3.79, and 2.43 log cycles, respectively, which is much lower than control. The pretreatments showed no significant effect to L. paracasei SNP2 survival to spray drying. Originality/value This is the first study of L. paracasei SNP2 resistance to heat shock and spray drying. This paper also enriches information about application of whey sucrose as a growth medium and a heating medium.