摘要:
为了探明哈茨木霉菌株发酵液乙酸乙酯提取物对致病疫霉生长的抑制机理，采用生化方法对经提取物处理的致病疫霉菌体内保护酶活性、菌体可溶蛋白含量、丙二醛（MDA）含量、电导率、呼吸速率的影响进行了研究。结果表明：提取物处理的致病疫霉菌体的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、过氧化物酶（POD）、谷胱甘肽过氧化物酶(GSH-Px)活性与对照相比显著降低，48 h分别下降了89.06%、86.96%、97.47%和97.63%；菌体处理48 h后可溶性蛋白含量下降了62.5%， 而MDA含量上升了60.98%；处理后病菌电导率一直呈上升状态，呼吸速率缓慢下降，处理48 h后，电导率上升了40.89%，呼吸速率下降为0。综上，哈茨木霉发酵液乙酸乙酯提取物可降低致病疫霉菌体可溶性蛋白含量，降低菌体保护酶（SOD、CAT、POD）活性，提高菌体MDA含量，提高菌体电导率，降低菌体呼吸速率。提取物处理后，致病疫霉系统清除自由基出现障碍、细胞膜被破坏、电解质外露，致使致病疫霉菌体遭受损坏，这可能是哈茨木霉发酵液乙酸乙酯提取物抑制致病疫霉生长的机理之一。
Abstract:
In order to know the inhibition mechanism of ethyl acetate extract of Trichoderma harzianum fermentation liquid on the growth of Phytophthora infestans, the effects of the extract on pathogen physiological indexes, such as protective enzyme activity, cell content of soluble protein, malondialdehyde (MDA) content, electrical conductivity and respiration rate, were studied by biochemical method. The results indicated that the pathogen’s protective enzyme activities decreased significantly after treated by extract. Forty-eight hours after treatment, the enzyme activity of SOD, CAT, POD and GSH-Px decreased by 89.06%, 86.96%, 97.47% and 97.63% respectively, content of soluble protein reduced by 62.5%, content of MDA increased by 60.98%, electrical conductivity increased by 40.89%, and respiration rate decreased to 0. In conclusion, ethyl acetate extract which was extracted from the fermented liquid of T. harzianum reduced the pathogen’s soluble protein content. Protective enzyme (SOD, CAT, POD and GSHPx) activity and respiration rate were also reduced. Ethyl acetate extract was also found to increase MDA content and electrical conductivity. This means the extract can cause the systems of P. infestans to be changed through, for example, scavenging free radicals, cell membrane damage and electrolyte exposure, resulting in the P. infestans body being damaged. This may be one of the inhibiting mechanisms of ethyl acetate extract of T. harzianum to the growth of P. infestans.
百度学术
下载:
