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Biogas slurry is the by-product of biogas anaerobic fermentation and has beencalled Bio-fertilizer and Biopesticide and widely popularized and applied in agriculturalindustry. But with the rapid development of biogas engineering in China, biogas slurryalso get mass production at the same time. Therefore, reutilization and harmlessutilization technology research is very significance and is effective way to achievehigh-value utilization for biogas slurry. At present, little has been reported about theorganic matter composition of biogas slurry and residue, and previous study found thatthe compounds isolated from biogas slurry, most of which were the phytohormone，freeamino acid，antibiotic，2-quinolinone and17-Estradiol. They showed promotion effectto plant growth, anti-microbial activity and etc. Therefore, this study contains twopurposes. The first, multiple compounds from biogas slurry of chicken manure wereisolited.The second, it is aimed to screen of compounds which showed antibacterial orother activity, in order to obtain the antibacterial compositions and lead compounds.Meanwhile, a large number of spectral data from the chemical substances of biogasslurry was accumulate, in order to provide the basis for high-value utilization of biogasslurry. This paper selected biogas slurry of chicken manure from livestock farm inShanghai Pudong New Area as the research object, so that the chemical substances wereisolated and identified and the compounds activity were assessed. By extraction,recrystallization and column chromatography including chromatography onnormal-phase silica gel, reverse-phased silica gel, Sepadex LH-20andsemi-preparative/analytical HPLC,14compounds were obtained, and8of them havebeen identified on the basis of spectroscopic analyses (IR, EI-MS, HR-ESI-MS,1H-NMR,13C-NMR,1H-1H COSY, HMQC, HMBC, NOESY and X-Ray Single CrystalDiffraction), and comparison with the literatures. From biogas slurry of chicken manure,8compounds were identified as24-Norolean-12-ene-3,22-dione (compund1),24-Norolean-4,12-diene-3,22-dione (compund2),3-Hydroxy-24-Norolean-12-ene-22-one (compund3),3-Hydroxy-24-Norolean-12-ene-22-one (compund4), S-equol (compund5),3,4-dihydro-8-hydroxyquinolin-2(1H)-one (compund6), o-coumaric acidamide (compund7) and Phenylacetic acid (compund8). Compounds1-4were newones and5-8were first isolated from biogas slurry of chicken manure. The others werestill under indentifying.The compounds1-5were tested in antibacterial activity. The results showed thatcompound1has antibacterial activity against Pseudomonas aeruginosa, Vibrioparahaemolyticus, Bacillus cereus, Escherichia coli, Listeria monocytogenes andStaphylococcus aureus. And antibacterial activity against Bacillus cereus,Staphylococcus aureus and Listeria monocytogenes were higher than Pseudomonasaeruginosa, Vibrio parahaemolyticus and Escherichia coli. Furthermore, S-equol(compound5) possesses good inhibitory activity (MIC48μg/ml) similar to oxacillinwhen their against Bacillus cereus. But compounds1-4have no inhibitory activity to allof six strians, even concentration at1mg/ml (compounds1and2) and12mg/ml(compounds3and4). The resluts in vitro cytotoxicity test showed that compound1(50μg/ml) was non-toxic to HeLa cell. Four new compounds (1-4) are pentacyclictriterpenes and that may be Soyasterol B transformed into these new compound s bymicrobial oxidation in chicken’s intestines and excreted outside with faeces and furtheroxidation in biogas digester. In previous paper, compound5(S-equol) and7(o-coumaric acid amide) had been confirmed that both have high antioxidative activity.Moreover, S-equol was also been approved to have a lot of biological activity, likeanti-breast and prostate cancer. Therefore, it is necessary to study on the relationbetween high biological activity compunds and microorganism from chicken’s intestinesand biogas digester. And we isolated and obtained antibacterial activity compoundsinclude S-equol,3,4-dihydro-8-hydroxyquinolin-2(1H)-one, o-coumaric acid amide andPhenylacetic acid，and well explain the biogas slurry’s bacteriostatic action.Thus, the study of biogas slurry aimed to clarify the antibacterial compounds andcarry out the objects of the new structure of pharmaceutical lead compounds, andaccumulate more compounds’ spectrum data which will enrich the biogas slurry studysystemic. There is very impotance for high-value utilization of biogas slurry and thatwould be certain social benefits.
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