Plasma Mutagenesis Of Ganoderma Lingzhi And Screening Through Infrared Spectroscopy For Medicinal Components

As a traditional Chinese medicine,Ganoderma lingzhi has received increasing attention in both scientific research and medical application.Modern medical research shows that G.lingzhi has many pharmacological effects such as immunomodulatory activity,regulation of cardiovascular function,regulation of blood glucose,and hepatoprotective effect.Therefore,it was embodied in the American Herbal Pharmacopoeia and therapeutic Compendium in 2000,and since 2016 it has been adopted in the United States Pharmacopoeia as medicinal raw materials.Ganoderma polysaccharides and triterpenes are the most important medicinal components.In order to expand the Ganoderma germplasm resources and select the Ganoderma strains with higher medicinal value,we chose the strain with high content of polysaccharides and triterpene as original strain for futer DBD low temperature plasma mutagenesis.After DBD plasma mutagenesis,10 mutagenic strains were comfirmed by RAPD test.There were significant differences in mycelia growth status,such as mycelia morphology,growth rate and surface color after liquid fermentation.The content of Ganoderma polysaccharides in some mutated strains was significantly different from that of the original strain.In order to analyze the effective medicinal components of G.lingzhi,we applied and developed the infrared spectroscopy analysis method.Firstly,the Ganoderma polysaccharides as an important medicinal components of G.lingzhi were analyzed by infrared spectroscopy.The Mid-and near-infrared spectra of Ganoderma fermentation mycelia were detected.We found that the characteristic peaks of mid-IR spectra of Ganoderma polysaccharides were at 1425 and 1078 cm-1.While the characteristic positions of near infrared spectrum were at 4307 and 4405 cm-1.The above positions can be used for the qualitative analysis with mid-IR and NIR spectra of Ganoderma polysaccharides.At the same time,according to the results of chemical determination of Ganoderma polysaccharides and NIR spectra,a quantitative model of Ganoderma polysaccharides based on NIR was established.The spectral range of the model was 5268.8～4000 cm-1,and the pretreatment method was first derivative.The ranks=6,R2=0.9779,RMSECV=0.467,RPD=6.73 in calibration set;while the RMSEP=0.603,RPD=3.13,corr.coeff.=0.9554 in prediction set.By detecting the spectra of mutated Ganoderma strains,we found that the NIR model mentioned above is also applicabile for quantitative analysis of the mutated Ganoderma strains.The RMSEP=0.445,Bias=0.132,RPD=2.75,corr.coeff.=0.9684 in prediction set.The results of NIR showed that the polysaccharide content of the high polysaccharide content strain,RWY-1,was 25.6%higher than that of the original strain.In addition,we employed infrared spectroscopy to analyze mutated strains’triterpene which is another important medicinal component in Ganoderma spp..In combination with other conventional chemical methods,we developed a qualitative and quantitative analysis method for triterpene by infrared spectroscopy.The characteristic positions of triterpenes were determined by mid-IR and NIR spectra of the fruiting bodies and mycelia of Ganoderma spp.from different origins.In the mid-infrared spectra,the characteristic peaks were at 1736,1377 and 1248 cm-1,respectively.In the near infrared spectra,the characteristic positions were 5902,4415 and 4350 cm-1,respectively.The mid-IR and NIR characteristic positions mentioned above can be used for qualitative analysis of triterpenes.Based on this,a quantitative analysis model of Ganoderma triterpene based on NIR was established.The selected ranges for the quantitative model is 5963.1～5662.3 cm-1 and 4412.56～4350.85 cm-1.The pretreatment method is first derivative.The Rank=4,R2=0.8857,RMSECV=0.267,RPD=2.97,Bias=-0.0195 in the calibration set,which has a good quantitative analysis effect.