[Chemical constituents with α-glucosidase inhibitory activities from seeds of Morinda citrifolia (Noni)].

The present study investigated the chemical constituents and inhibitory activities against α-glucosidase from the seeds of Morinda citrifolia(Noni) by the chromatographic technique and semi-preparative HPLC.Fifteen compounds were isolated from the ethyl acetate extract of the seeds, and their structures were identified on the basis of physiochemical characteristics and spectroscopic data as(9S,2E,4Z,7Z)-9-hydroxydeca-2,4,7-trienoic acid(1), azelaic acid(2), scopoletin(3), ursolic acid(4), quercetin(5), cyclo-(L-Leu-L-Ile)(6), cyclo-(L-Phe-L-Ile)(7), cyclo-(L-Phe-L-Val)(8), cyclo-(L-Leu-L-Val)(9), cyclo-(L-Phe-L-Leu)(10), caffeic acid(11), 3,4-dihydroxycinnamaldehyde(12), p-hydroxybenzoic acid(13), p-hydroxy-cinnamic acid(14), and p-hydroxyphenethyl alcohol(15).Among them, compound 1 was a new fatty acid and compounds 7-10 and 12 were isolated from Morinda plant in the Rubiaceae family for the first time.Compounds 1, 2 and 4-15 were isolated from the seeds of M.citrifolia(Noni) for the first time.All isolated compounds were evaluated for the inhibitory activities against α-glucosidase and compounds 3-5 showed potential inhibitory activity with IC_(50) values of 160, 133, and 120 µmol·L~(-1), respectively.

[Influence of Temperature on the Anaerobic Packed Bed Reactor Performance and Methanogenic Community].

This study aimed to analyze the effect of temperature on performance and microbial community structure of an anaerobic packed bed reactor (APBR). The temperature was increased step-wise from room temperature (22 degrees C ± 1 degrees C) to psychrophilic (15 degrees C ± 1 degrees C), mesophilic (37 degrees C ± 1 degrees C) and thermophilic (55 degrees C ± 1 degrees C). The results showed that, in the temperature changing process, the higher the temperature of APBR was, the higher COD removal rate and daily gas production were. After temperature changed to psychrophilic, mesophilic and thermophilic, COD removal rate and daily gas production were 25%, 45%, 60% and 2.3 L x d(-1), 4.0 L x d(-1), 8.5 L x d(-1) respectively. However, there was no significant change in biogas composition (-60%). A sudden temperature change caused a simultaneous increase in the concentration of volatile fatty acids (VFA), which had been fluctuating. Using 16S rRNA gene clone library screening, Euryarchaeota was commonly found, including important methanogens: MBT (Methanobacteriales), Mst (Methanosaetaceae) , Msc (Methanosarcinaceae) and MMB (Methanomicrobiales), as well as thermophilic bacteria and few spring Archaea. However, the diversity of methanogenic groups was reduced, especially at mesophilic. The results of quantitative PCR showed that the 16S rRNA gene concentrations of Mst, MMB and Msc were reduced by temperature changes. Although the relative proportion of every kind of methanogen was significantly affected, Mst was the dominant methanogen.