不同光照强度和培养时间下铁皮石斛类原球茎生物量、多糖和生物碱量的动态变化

目的探讨不同光照强度下铁皮石斛类原球茎(PLBs)生物量、主要药用成分多糖和生物碱的动态变化规律。方法以MS为基本培养基,采用光照强度单因素试验设计,烘干法测定生物量,苯酚-硫酸法测定多糖量,酸性染料比色法测定生物碱量,数据采用SPSS 16.0软件包分析。结果铁皮石斛PLBs生物量在光照强度≥2 000 lx下培养40～50 d均较高,生产上需要PLBs维持旺盛的分裂,获得最高生物量的培养条件为光照强度2 000 lx条件下培养40 d,生物量达到0.74 g;多糖量以光照强度2 000 lx下培养30 d最高,达到16.88%;生物碱量以光照强度500 lx下培养30 d最佳,达到0.028 0%。结论不同的光照强度和培养时间对铁皮石斛PLBs的生长、多糖和生物碱的变化有显著影响,适宜的光照强度和培养时间对铁皮石斛主要药用成分的生产具有重要的实践意义。

Dynamic variation of biomass and content of polysaccharide and alkaloid in protocorm like bodies from Dendrobium officinale at different light intensities and incubation time

Objective To explore the dynamic variation of biomass and content of polysaccharide and alkaloid in protocorm-like bodies(PLBs) from Dendrobium officinale at different light intensities and incubation time.Methods Taking MS as medium,with light intensity single-factor test design,the biomass was determined by drying method,polysaccharide by phenol-sulfuric acid method,alkaloid content by acid dye colorimetry,and the data used SPSS 16.0 software analysis.Results The results indicated that the biomass content of PLBs from D.officinale was higher under the light intensity ≥ 2 000 lx for 40—50 d incubation.PLBs from D.officinale needed to maintain the most effective in strong production split under the light intensity of 2 000 lx for 40 d incubation and the maximum biomass was 0.74 g.In this condition,PLBs could keep the strong split,the maximum polysaccharide content was the highest 16.88% under light intensity 2 000 lx for 30 d incubation.Light intensity at 500 lx for 30 d incubation was beneficial to alkaloid content,the maximum was 0.028 0%.Conclusion Different light intensities and incubation time have significant influences on the growth of PLBs from D.officinale,and the accumulation of polysaccharide and alkaloids.Suitable light intensity and incubation time have very important practical significances to produce medical ingredients of PLBs from D.officinale.