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膜醭毕赤酵母（Ｐｉｃｈｉａ ｍｅｍｂｒａｎｅｆａｃｉｅｎｓ Ｈａｎｓｅｎ）和季也蒙假丝酵母（Ｃａｎｄｉｄａ ｇｕｉｌｌｉｅｒｍｏｎｄｉｉ）是两株能有效抑制桃、油桃果实采后软腐病的拮抗菌．研究了拮抗菌的β－１，３－葡聚糖和几丁酶活性在ｉｎ ｖｉｔｒｏ 和ｉｎ ｖｉｖｏ上的诱导．结果表明，以葡萄糖＋细胞壁制品（ＣＷＰ）作为碳源时在Ｌｉｌｌｙ－Ｂａｒｎｅｔｔ基本培养基中诱导的（ －１，３－葡聚糖活性最高，其中膜醭毕赤酵母和季也蒙假丝酵母的最高值分别达１１４．０ ＳＵ（ｓｐｅｃｉｆｉｃ ａｃｔｉｖｉｔｙ ｕｎｉｔ， 比活单位）和１０３．２ ＳＵ，而以葡萄糖作为惟一碳源时诱导的β－１，３－葡聚糖活性则最低．在Ｃｚａｐｅｃｋ 基本培养基中，膜醭毕赤酵母诱导的几丁酶（外切及内切几丁酶）活性显著地高于季也蒙假丝酵母，如膜醭毕赤酵母外切几丁酶最大活性达３．１３ ＳＵ，显著地高于季也蒙假丝酵母的最大活性（２．２４ ＳＵ）．酵母菌悬浮液和碳源也能诱导桃果实伤口处β－１，３－葡聚糖和几丁酶的产生．研究表明β－１，３－葡聚糖和几丁酶在抑制病菌时都有一定作用，并可能具有协同效果．
Pichia membranefaciens Hansen and Candida guilliermondii are the two antagonistic bacteria that can effectively inhibit the postharvest soft rot of peach and nectarine fruit. The in vitro and in vivo induction of β-1,3-glucan and chitinase activity of antagonistic bacteria was studied. The results showed that the Lilly-Barnett minimal medium was induced with glucose + cell wall product (CWP) as the carbon source (the highest activity of 1,3-glucan, in which Pichia membranaceus and Candida sesbania The highest activity was 114.0 SU (specific activity unit) and 103.2 SU, respectively, while the lowest activity of β-1,3-glucan induced by glucose as sole carbon source was the lowest in Czapeck In the medium, the activity of chitinase (exo-and chitinase) induced by Pichia pastoris was significantly higher than that of Candida setae, such as the maximum activity of chitinase 3.13 SU, which was significantly higher than that of Candida senticosus (2.24 SU). Saccharomyces cerevisiae suspension and carbon source were also able to induce β-1,3-glucan in peach fruit and several Butyrase production. Studies have shown that β-1,3-glucan and chitinase have a role in inhibiting bacteria And it may have a synergistic effect.