title: Microbial diversity analysis of fermented mung beans (Lu-Doh-Huang) by using pyrosequencing and culture methods.
abstract: In Taiwanese alternative medicine Lu-doh-huang (also called Pracparatum mungo), mung beans are mixed with various herbal medicines and undergo a 4-stage process of anaerobic fermentation. Here we used high-throughput sequencing of the 16S rRNA gene to profile the bacterial community structure of Lu-doh-huang samples. Pyrosequencing of samples obtained at 7 points during fermentation revealed 9 phyla, 264 genera, and 586 species of bacteria. While mung beans were inside bamboo sections (stages 1 and 2 of the fermentation process), family Lactobacillaceae and genus Lactobacillus emerged in highest abundance; Lactobacillus plantarum was broadly distributed among these samples. During stage 3, the bacterial distribution shifted to family Porphyromonadaceae, and Butyricimonas virosa became the predominant microbial component. Thereafter, bacterial counts decreased dramatically, and organisms were too few to be detected during stage 4. In addition, the microbial compositions of the liquids used for soaking bamboo sections were dramatically different: Exiguobacterium mexicanum predominated in the fermented soybean solution whereas B. virosa was predominant in running spring water. Furthermore, our results from pyrosequencing paralleled those we obtained by using the traditional culture method, which targets lactic acid bacteria. In conclusion, the microbial communities during Lu-doh-huang fermentation were markedly diverse, and pyrosequencing revealed a complete picture of the microbial consortium.
authors.affiliation: Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shiou-Huei
authors.initials: SH
authors.lastname: Chao
authors.forename: Hui-Yu
authors.initials: HY
authors.lastname: Huang
authors.forename: Chuan-Hsiung
authors.initials: CH
authors.lastname: Chang
authors.forename: Chih-Hsien
authors.initials: CH
authors.lastname: Yang
authors.forename: Wei-Shen
authors.initials: WS
authors.lastname: Cheng
authors.forename: Ya-Huei
authors.initials: YH
authors.lastname: Kang
authors.forename: Koichi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Ying-Chieh
authors.initials: YC
authors.lastname: Tsai
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D000529:Complementary Therapies; D046508:Culture Techniques; D007887:Fabaceae / Q000382:microbiology*; D005285:Fermentation; D005798:Genes, Bacterial; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011938:Rec A Recombinases / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D012336:RNA, Ribosomal, 16S; D011938:Rec A Recombinases