著者
Hiroyuki Nakagawa Hidetoshi Nagamasu Shuichi Nemoto Shizuka Fuse Atsushi Ebihara Kohtaroh Shutoh
出版者
The Japanese Society for Plant Systematics
雑誌
Acta Phytotaxonomica et Geobotanica (ISSN:13467565)
巻号頁・発行日
vol.73, no.2, pp.151-157, 2022-06-30 (Released:2022-07-24)

Leymus komarovii (Roshev.) J. L. Yang & C. Yen (Triticeae, Poaceae) is a rare species in Japan, reported only twice from Hokkaido. In 2018, an additional specimen of L. komarovii was collected in Oketo-cho, Tokoro-gun, Hokkaido. Subsequent examination of specimens in Japanese herbaria revealed that its distribution range in Hokkaido was wider than previously known. Asperella longearistata (Hack.) Ohwi f. glabra Ko. Ito, described from Hokkaido, is reduced to synonym under L. komarovii and a lectotype for Hystrix sachalinensis Ohwi, another synonym of L. komarovii, is designated, superseding a previous lectotypification. A detailed description of L. komarovii based on Japanese materials and a key to the Japanese taxa of Leymus is provided.
著者
Motoi Tamura Hiroyuki Nakagawa Kazuhiro Hirayama
出版者
Japanese Society for Food Science and Technology
雑誌
Food Science and Technology Research (ISSN:13446606)
巻号頁・発行日
pp.FSTR-D-22-00117, (Released:2022-11-11)

Isorhamnetin (3′-methylquercetin) is one of the major metabolites of quercetin. We hypothesized that Eubacterium limosum JCM6421 T transforms isorhamnetin back to quercetin and the type of sugar affects short-chain fatty acid production by E. limosum JCM6421T. Anaerobic broth (0.2 mL) containing this bacterium was added to the isorhamnetin solution and anaerobically incubated for 8 and 24 h. Additionally, E. limosum JCM6421T was anaerobically incubated with various 2 µL-sugar solutions for 24 h and short-chain fatty acid production by this bacterium was measured. Quercetin was produced by anaerobic incubation of isorhamnetin with E. limosum JCM6421T. Its production increased with an increase in incubation time from 8 to 24 h. Mannitol was the ideal sugar for butyric and acetic acid production by E. limosum JCM6421T among the investigated sugars. We discovered that E. limosum JCM6421T produces quercetin from isorhamnetin.
著者
Motoi Tamura Hiroyuki Nakagawa Sachiko Hori Tadahiro Suzuki Kazuhiro Hirayama
出版者
SOCIETY FOR FREE RADICAL RESEARCH JAPAN
雑誌
Journal of Clinical Biochemistry and Nutrition (ISSN:09120009)
巻号頁・発行日
vol.65, no.3, pp.232-239, 2019 (Released:2019-11-01)
参考文献数
36
被引用文献数
6

Protective effect of quercetin on high-fat diet-induced non-alcoholic fatty liver disease in mice has been reported. Recent research has revealed that several intestinal bacteria metabolize quercetin. We hypothesize that the difference in composition of intestinal microbiota affects quercetin absorption from the intestine. Germ-free BALB/cA female mice (18 weeks old) were randomly divided into four groups and orally administered with fecal suspension from four human individuals (HF1, HF2, HF3, HF4) to produce the human microbiota-associated mice. All mice were fed the 0.05% quercetin-containing pelleted diet for four weeks. Significant differences were observed in plasma total cholesterol and cecal microbiota among the four groups. Plasma quercetin concentration was significantly higher in the HF3 group than in the HF1 group. The plasma isorhamnetin/quercetin ratio showed significant negative correlation with visceral fat levels (r = −0.544, p = 0.013). Positive correlation was observed between the Log10 Enterobacteriaceae count and the plasma quercetin metabolites. Principal component analysis showed that all groups were distributed in different regions by using the correlation diagram with the second and third principal component. This study indicates that intestinal microbiota of human microbiota-associated mice inoculated with different fecal suspensions react to dietary quercetin in different ways.