Search

Genetic and environmental factors influence the growth and quality of medicinal plants. In recent years, rhizosphere microorganisms have also emerged as significant factors affecting the quality of medicinal plants. This study aimed to identify Schisandra resources with high lignan content and analyze the microbial diversity of the rhizosphere soil. High-performance liquid chromatography was used to measure the lignan content in nine Schisandra fruits. High-throughput sequencing was used to analyze the 16S rDNA sequences of rhizosphere bacteria to identify bacterial species diversity. The total lignan content of the nine Schisandra resources ranged from 9.726 mg/g to 14.031 mg/g, with ZJ27 having the highest content and ZJ25 the lowest. Among the six lignan components, Schisandrol A had the highest content, ranging from 5.133 mg/g to 6.345 mg/g, with a significant difference between ZJ25, ZJ27, and other resources ( p < 0.05). Schizandrin C had the lowest content, ranging from 0.062 mg/g to 0.419 mg/g, with more significant differences among the resources. A total of 903,933 sequences were obtained from the rhizosphere soil of the nine Schisandra resources, clustered into 10,437 OTUs at a 97% similarity level. The dominant bacterial phyla were Actinobacteriota , Acidobacteriota , Proteobacteria , Chloroflexi , Gemmatimonadota , and Verrucomicrobiota . The dominant bacterial genera were Candidatus&#95;Udaeobacter , Candidatus&#95;Solibacter , RB41 , Bradyrhizobium , Gaiella , and Arthrobacter . ZJ27 is the Schisandra resource with the highest lignan content, and the rhizosphere bacteria of Schisandra are rich in diversity. Schisandra B is negatively correlated with Bryobacter , Candidatus&#95;Solibacter , and unnamed genera of Gaiellales .

SO 2 plays an important role in wine fermentation, and its effects on wine aroma are complex and diverse. In order to investigate the effects of different SO 2 additions on the fermentation process, quality, and flavor of 'Beibinghong' ice wine, we fermented 'Beibinghong' picked in 2019. We examined the fermentation rate, basic physicochemical properties, and volatile aroma compound concentrations of 'Beibinghong' ice wine under different SO 2 additions and constructed a fingerprint of volatile compounds in ice wine. The results showed that 44 typical volatile compounds in 'Beibinghong' ice wine were identified and quantified. The OAV and VIP values were calculated using the threshold values of each volatile compound, and t the effect of SO 2 on the volatile compounds of 'Beibinghong' ice wine might be related to five aroma compounds: ethyl butyrate, ethyl propionate, ethyl 3-methyl butyrate-M, ethyl 3-methyl butyrate-D, and 3-methyl butyraldehyde. Tasting of 'Beibinghong' ice wine at different SO 2 additions revealed that the overall flavor of 'Beibinghong' ice wine was the highest at an SO 2 addition level of 30 mg/L. An SO 2 addition level of 30 mg/L was the optimal addition level. The results of this study are of great significance for understanding the effect of SO 2 on the fermentation of 'Beibinghong' ice wine.