不同温型巨大侧耳菌株的生物学特性及液体发酵条件研究

Biological Characteristics and Liquid Fermentation Conditions of Pleurotus giganteus Strains with Different Temperature Types

巨大侧耳(Pleurotusgiganteus)是国内新开发的一种珍稀食用菌,具有典型的耐高温特性,在热区食用菌产业发展中具有重要地位。本团队通过前期在热区进行巨大侧耳的规模化栽培,筛选到2株具有不同出菇温型的菌株,分别适合于热区的热季和凉季栽培,可有效保障当地巨大侧耳市场的全年供应。为充分了解巨大侧耳的菌丝体营养需求和适宜培养条件,本研究以筛选到的高温型(PG46)和中温型(PG79)巨大侧耳菌株为材料,采用单因素和正交试验方法,比较和分析2株菌的生物学特性和液体发酵条件,并对液体发酵中菌丝体生长的动态变化规律进行研究。生物学特性研究结果表明:在单因素试验中,PG46和PG79的生长条件基本一致,最适碳源为麦芽糖,最适氮源为酵母浸粉和蛋白胨,最适pH为7,最适温度为25~28℃;但在30℃时,中温型菌株PG79的菌丝体开始遭受高温胁迫,菌落形态开始出现不规则现象;正交试验论证了单因素结果,且各因素对菌丝生长的影响程度均为:氮源>pH>温度>碳源。液体发酵试验结果显示:在生物学特性基础上,当摇床转速为150 r/min,装液量为120 mL,接种量为12%时,更适宜巨大侧耳菌丝体生长;PG46和PG79的菌丝体生长均呈“对数增长”的动态模式,分别在第15天(0.95 g)和第13天(1.09g)获得最高菌丝生物量,且PG79始终高于PG46,与平板上的生长速率差异一致(PG79>PG46)。研究结果可为不同温型巨大侧耳的规模化栽培、高温胁迫条件优化、杂交育种,以及深入开展巨大侧耳的表型和基因型研究提供参考。

Pleurotus giganteus is a kind of rare edible fungus newly developed in China.It has typical high temperature resistance and plays an important role in the development of edible fungus industry in tropics.With the large-scale cul-tivation of P.giganteus in tropics,two strains with different fruiting temperature types were selected,which are suitable for cultivation in hot season and cold season respectively,and can effectively ensure the annual supply of the local P.giganteus market.In order to fully understand the nutritional needs and suitable culture conditions of P.giganteus mycelia, the screened high-temperature strain (PG46) and med-temperature strain (PG79) of P. giganteus were used as the materials to compare and analyze the biological characteristics and liquid fermentation conditions with single factor and orthogonal experimental methods, and the dynamic changes of mycelia growth in liquid fermentation were further stud-ied. The experimental data were analyzed by SPSS 26 software. The experiment results of biological characteristics showed that in the single factor experiment, the growth conditions of PG46 and PG79 were basically the same, the op-timal carbon source was maltose, the optimal nitrogen sources were yeast extract powder and peptone, the optimal pH was 7, and the optimal temperature was 25-28 ℃. However, the mycelia of PG79 began to suffer from heat stress at 30 , and the℃ colony morphology became irregular. The orthogonal experiment proofed the single factor results, and the impact order of each factor on the mycelia growth of P. giganteus was: nitrogen source > pH > temperature > carbon source. The experimental results of liquid fermentation showed that on the basis of biological characteristics, when the rotating speed was 150 r/min, the liquid volume was 120 mL, and the inoculation amount was 12%, it was more suitable for the mycelia growth of P. giganteus. The mycelial growth of PG46 and PG79 showed a dynamic pattern of “loga-rithmic growth”, and the highest mycelia biomass was obtained at 15 d (0.95 g) and 13 d (1.09 g) respectively. The my-celia biomass of PG79 was always higher than that of PG46, which was consistent with the difference in growth rate between them (PG79>PG46). The study could provide references for the large-scale cultivation of P. giganteus strains with different temperature types, the optimization of heat stress conditions, cross breeding, and the further study of the phenotype and genotype of P. giganteus.