12个金针菇菌株菌丝的生长速度及胞外酶活力比较
DOI:10.14088/jki.issn0439-8114.2016.22.032
Study on the Hypha Growth Speed and Extracellular Enzymes Activity of 12 Strains of Flammulina velutiper ZHAO Shu-ying1,WANG Li-an2
(1. College of Physical Education, Cangzhou Normal University, Cangzhou 061001, Hebei, China;
2. College of Life Science, Hebei Normal University, Shijiazhuang 050021, China)
: The hypha growth speed and colony characteristics of 12 stains of Flammulina velutiper (Fr.) Sing commonly used on the production was compared. Moreover, the activity of their extracellular enzymes, such as Carboxymethyl cellulose, xylanase, laccase enzyme were determined in order to find out the relationship between hypha growth rate and extracellular enzyme activity so as to provide scientific basis for evaluation of strain quality. The experimental results show that the growth speed of strain No.9 and No.12 was faster than the others on PDA medium with rich inorganic salts and vitamin; while the growth speed of strain No.7, No.8, and No.12 was faster
than others on simulated mushroom medium. Carboxymethyl cellulase is the most active in strain No.5; while xylanase and laccase is the most active in strain No.1. The contingency between extracellular enzyme activity and speed coupling is poorer.
金?菇[Flammulina velutiper(Fr.)Sing.]是味道鲜美、营养丰富的食用菌之一,同时又具有良好的保健价值,在国内许多地区都有栽培,金针菇产业的发展对促进当地经济和社会发展起到了重要推动作用。但在金针菇生产上也出现一些问题,一是所用金针菇菌种普遍退化、老化,造成菇农栽培风险加大,经济效益下滑;二是金针菇菌种市场极为混乱。由于目前食用菌菌种质量评价的科学体系还不完善,菌种质量和产销管理薄弱,一定程度上造成了食用菌菌种杂、多、乱的混乱现象,严重损害了菇农利益。为了解决以上问题,试验选择12个金针菇菌株为材料,通过测定胞外酶活力,试图建立快速评价菌种质量的检测体系,即找出胞外酶活力与生长速率的内在联系,从而建立不同菌株的酶活力数据库来评价菌种质量,为金针菇菌种质量保障提供技术支撑。现将结果报告如下。 1 材料与方法 1.1 材料
12个不同金针菇菌株均为当地金针菇主栽菌种,现保存于河北师范大学生命科学学院实验室。具体编号为1号:白金F21;
2号:金针FV093;3号:金针1008;4号:金科佳2041;5号:金针日金1号;6号:金F39;7号:金针1301;8号:金针2102;9号:三明B;10号:金杂19;11号:福建白金针;12号:三明C。
主要仪器有756MC紫外可见分光光度计、电热恒温水浴锅、恒温培养箱、超净工作台、电磁炉、电子分析天平、RE-5203旋转蒸发器、振荡器、78-1磁力加热搅拌器、立式自动电热蒸汽灭菌器等。 胞外酶活力测定的主要试剂有3,5-二硝基水杨酸(DNS,显色剂)、醋酸钠缓冲液(0.1 mol/L,pH 4.6)、邻联甲苯胺、木聚糖溶液,底物为1%的羧甲基纤维素钠溶液。 1.2 菌种培养
1.2.1 培养基 分别制作PDA培养基、PDA加富培养基、模拟出菇培养基。
1.2.2 不同菌株菌丝生长速度的测定 将4 ℃冰箱保存的试管母种分别接种到PDA加富培养基平板上,25 ℃下培养7 d后备用[1]。将活化的菌丝沿菌落的边缘用打孔器切下直径8 mm的菌块,分别接种于PDA加富培养基平板及模拟出菇培养基平板上,每个菌种3次重复,于25 ℃恒温培养箱内培养,2 d后每天定时精确测量菌落半径,同时观察记录菌株的菌落形态,按下式计算菌丝生长速度[2],
菌丝生长速度(mm/d)=菌落半径(mm)/菌丝生长天数(d)。 1.3 胞外酶活力测定
1.3.1 酶液的制备 将在模拟出菇培养基上培养的菌落沿菌落边缘挖取发菌料各1 g于试管中,加入0.1 mol/L醋酸钠缓冲液10 mL(pH 4.6),4 ℃浸提4 h;将浸提液用滤纸过滤即得粗酶液。用于测定羧甲基纤维素酶、木聚糖酶、漆酶活力,测定时将各酶液稀释10倍[3]。
1.3.2 羧甲基纤维素酶活力测定