Study On Chemical Constituents And Biological Activities Of Distiller's Grains And Koji From Maotai Town, Guizhou Province

The chemical constituents and biological activities of the distillers' grains and yeast from the town of Maotai were investigated and reported in this thesis.Moutai grants and yeast were extracted by 75% ethanol. The purification of the extracts were conducted via various methods including normal-phase silica gel column chromatography, reversed-phase silica gel column chromatography, Sephadex LH-20 gel column chromatography, thin layer chromatography, macroporous resin column chromatography and recrystallization. Ten compounds were isolated and identified from Maotai lees, namely, succinic acid(JZY-1), diphenyl(JZY-2),3,5-dihydroxybenzoicacid(JZY-12), 3',5'-Dimethoxy-3,5,7-Trihydroxyflavone(JZY-14), oleanic acid(JZY-17), ursolic acid(JZY-20), 2-furoic acid(JZY-21),?-sitosterol(JZY-22), 2,5-piperazinedione-3,6-bis-(2-methylpropyl)(JZY-23),2-anilino-1,4-naphthoquinone(JZS-3). Seven compounds were isolated and identified from distillers' yeast. They are: palmitic acid(JQS-3), ?-sitosterol(JQY-2),syringic acid(JQY-3), 4-hydroxybenzoic acid(JQY-4), ursolic acid(JQY-5), lauric acid(JQY-7) and Vanillin(JQY-9). It is the first time in history to isolate and identify the compounds mentioned above from the distillers' grains and yeast.We applied gas chromatography mass spectrometry technology(GC-MS) to analyze the petroleum ether extract of Maotai distiller's grain and yeast, which were the fat soluble components of the extract. Eighteen compounds, accounting for 100%of the peak area, were identified and their structures were determined. These components mainly include esters, acids and alkanes. The major components from distiller's grains were linoleic acid ethyl ester(22.34%), ethyl oleate(15.50%),palmitic acid ethyl ester(11.38%), and pentacosane(10.68%). The major components from the starter included tricosane(14.70%), tetracosane(14.23%), pentacosane(12.48%), and hexacosane(10.98%).Total flavonoids in Maotai distiller's grains and yeast were determined by applying ultraviolet spectrophotometry method using quercetin as standard reference.They were 20.40mg/g in the grants and 9.695mg/g in the yeast respectively. We alsoapplied Folin-Ciocateu colorimetry to determine the total polyphenols in distiller's grants and yeast. Gallic Acid was used as standard reference. 4.78 mg/g of polyphenols in distiller's grants and 1.84 mg / g of polyphenols in distiller's yeast were determined. We optimized the determination conditions to ensure the accuracy of the analytic data.Three methods, namely DPPH, ABTS and FRAP, were applied to test in vitro antioxidant activity of various parts of the distiller's grains and yeast. The results showed that the ethyl acetate fractions of both distiller's grains and yeast had good scavenging effects for ABTS radical elimination. While they had poor effects for scavenging DPPH free radical and Fe ion reduction.Double K-B method and tube dilution method were used for the determination of the minimum inhibitory concentrations of petroleum ether extracts and 75% ethanol extracts of distiller's grains and yeast. The results showed that petroleum ether extracts of distiller's yeast had good effects on the inhibition of staphylococcus aureus(SA), methicillin-resistant staphylococcus aureus(MRSA) and extended spectrum?-Lactamases staphylococcus aureus(ESBLs-SA), while the effect of inhibiting MRSA was the best. The petroleum ether extract of distiller's grains had a weak inhibitory effect on MRSA, and no antibacterial activity for SA and ESBLs-SA. In contrast, ethanol extracts of both distiller's grants and yeast had better antibacterial effects against bacillus subtilis, Escherichia coli and staphylococcus aureus.We applied sulforhodamine protein staining(SRB assay) method and nitroblue tetrazolium salt reduction method(MTT assay) and used adriamycin(ADM) as positive control to determine the extracts of distiller's grains and yeast against human lung cancer cells(A549) and human leukemia cells(K562)in vitro. The results showed that both 75% ethanol extract and petroleum ether extract of distiller's grains and yeast had a weak inhibition on K562 cell, and the extracts of 75% ethanol and ethyl acetate extract of distiller's yeast had a weak inhibition activity on A549 cell.