核桃内生菌研究Ⅱ核桃内生菌G8发酵产物的抑菌活性研究

Studies on Endophytic Fungi from Juglans regia L. Ⅱ Antimicrobial Activity of the Fermentation Metabolites Produced from an Endophyte G8 of Walnut

从核桃根部分离得到一株真菌,编号为G8。对其进行生物学观察,初步鉴定为葡萄壳小球孢菌,并进行了复侵染研究,确定其为核桃内生菌。对此菌株进行液体发酵,研究了其发酵液及其萃取物的抑菌活性。结果表明:①发酵液的提取物对28种植物病原真菌均有不同程度的抑制作用,各萃取相粗提物在40 mg.mL-1时,乙酸乙酯萃取物的抑制效果最好,其次为正丁醇萃取物,萃余物最弱,但正丁醇萃取物对水稻纹枯、杨树溃疡、小麦雪腐病原菌的抑制率大于其他两相。②不同浓度的乙酸乙酯萃取物对11种病原真菌的活性试验表明,对苹果轮纹、苹果腐烂、小麦根腐和稻瘟4种病原菌的抑制率为100%,不同浓度对苜蓿炭疽、小麦赤霉、番茄早疫、苹果炭疽和玉米小斑5种病原菌的抑制率表现出极显著差异,对玉米大斑和辣椒疫霉2种病原菌的抑制率无显著差异。③乙酸乙酯萃取物对5种细菌的抑菌试验表明,其对蜡状芽孢杆菌和马铃薯芽孢杆菌2种细菌表现为抗药性,但不同浓度处理间差异不显著。

A fungus separated from walnut＇s root has been numbered G8. The G8 is an endophyte which has been identified through biological observation and renewed invasion, and idenifies as Coniothyrium, vitivora Mitura initially. To study the antimicrobial activity of the fermentation products and its extracts. Fermented the fungus in liquid PDA. The results showed that. （1）The extracts of fermentation all have different range activity to 28 kinds pathogenic fungi, at concentration 40 mg·mL^-1, the inhabited effect of the phases is acetyl acetate, butanol and residue from strong to weak, but the inhabitation of butanol extract is better than the two other phases to Thanatephorus cucumeris, Dothiorella gregaria and Monographella nivialis. （2）Different concentrations of acetyl acetate extract have been measured to 11 kinds pathogenic fungus. The results showed the inhabiting rate of the extract is 100% to Physalospora piricola, Valsa mall miyabe et. , Cochliobolus sativus and Magna porthe. The inhabited rate of Colletotrichum humtrifolii , Fusarium graminearum , Alternaria solani , Glomerella cingnlata, schr. et. and Bipolaris maydis to different concentration have been obvious difference.（3）The extract of acetyl acetate have studied on inhabited effect of 5 species bacteria. Bacillus megaterium and Bacillus mesenterius is sensitive to drugs, but not dominant to different concentration.