Diversity of bacteria inhabiting in natural fermented foods has been studied. Notably, recent development on next generation sequencer has shed light on complex microbiota of those fermented foods. In this review, we discuss the validity of pyrotag method to analyze microbiota of fermented foods by citing several publications, especially, our own studies on fermented rice bran, nukadoko.

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Pluripotent stem cells are able to differentiate into all types of cells in the body and have great potential for applications in regenerative medicine. However, the fact that the isolation and establishment of human ES cell lines involve embryo destruction leads to extensive ethical concerns and debates. iPS cells, from fibroblasts with four Yamanaka factors, share a similar gene expression profile and differentiation potential with ES cells. Although the successful derivation of iPS cells solves the problems of ethical issues and immunological rejection, there are concerns about the safety of using iPS cells for therapeutic applications. Recently, our group reported the generation of multipotent cells from adult human dermal fibroblast cells by incorporating lactic acid bacteria. In this review article, I will overview the history for our discovery and introduce the potential wide-ranging implications of our multipotent cells for cell generation, reprogramming, and cell-based therapy.

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Recent development of molecular targeting drugs against cancer is remarkable and attractive. On one hand, the population of cancer cells is heterogeneous due to the phenotypic instability of cancer cells, resulting in the appearance of drug-resistant and metastatic cells. Thus, the complete suppression of cancer is still difficult, and the troublesome situation is similar to hitherto chemotherapy. Therefore, it seems to be necessary to seek for targets in microenvironment of cancer tissues rather molecular targets in cancer cells, leading to attack whole cancer tissues like a surgery. We are developing Drug Delivery and Production System (DDPS) to selectively deliver and/or produce a large amount of anticancer drugs at a lesion part, directing attention to characteristic hypoxia in the solid cancer. As the delivery tool and micro production plant, we used non-pathogenic and anaerobic bifidobacteria. We established recombinant bifidobacteria expressing cytosine deaminase (CD) that coverts 5FC(low-toxic pro-drug) to 5FU.When tumor-bearing animals were treated by iv injecting the recombinant bacteria with CD followed by po 5FC administration, suppression of tumor growth was observed without any side effects. Although our cancer treatment system with Bifidobacterium has been criticized with a priori sense that iv injection of bacteria is dangerous, various biological tests indicated the safety of our cancer treatment system with Bifidobacterium, leading to the clinical phase 1 test.

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Some strains of lactic acid bacteria (LAB) can produce antimicrobial peptides, bacteriocins. LAB bacteriocins generally exert antibacterial activity through quick action on bactetrial cell membrane and can be degraded easily by intestinal digestive enzymes without leaving residues to the environment, which lets them considered as safe antimicrobial agents. In particular, nisin A produced by some strains of Lactococcus lactis has been being utilized as a food preservative in more than 50 countries including Japan. To realize safe microbial control using LAB bacteriocins, we have developed various applications of nisin A as well as discovered and characterized novel LAB bacteriocins with good properties for applications. In this review, we outline nisin A and other LAB bacteriocins and introduce our recent studies on applications of nisin A such as oral care agents, and screening and characterization of novel LAB bacteriocins such as lacticin Q and lactocyclicin Q.

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