ABSTRACT
Objective: The genetic diversity of wild Bletilla striata from different sources was analyzed in order to provide the reference value for breeding, protection and development of B. striata germplasm in the future. Methods: Genetic diversity of 50 wild B. striata samples was identified by SRAP molecular marker technique, and the genetic relationship was analyzed by UPGMA method. Results: A total of 117 bands were amplified from 50 samples by using 15 SRAP primer combinations, with an average of 7.8 bands per primer. Among them, 106 bands were polymorphic, with a polymorphism rate of 90.60%. The clustering results showed that the genetic similarity coefficient of 50 B. striata samples was 0.59-0.87, which could be divided into six categories based on the genetic coefficient of 0.66. The genetic distance of two pieces of B.striata from No.2 Lijiang, Yunnan and No.2 Jingshan County, Hubei was not directly related to geographical distance. Conclusion: There are abundant genetic diversity among wild B. striata resources, and there is no direct relationship between geographical distance and genetic distance. SRAP technology can provide theoretical basis for the protection of B. striata resources and variety breeding, which provides reference for the subsequent development and utilization of B. striata.
ABSTRACT
Objective: To study the low polar chemical constituents from the tubers of Bletilla striata. Methods: Silica gel, Sephadex LH-20 column chromatography, and preparative thin layer chromatography were used for the isolation and purification, the chemical structure was identified by the methods of high resolution mass spectrometry (HRMS) and NMR spectroscopic analyses, and the bioactivity of the compound was examined by the method of MTT. Results: A new chlorinated-steroid was obtained during the study on the chemical constituents of B. striata, its structure is 4-chloro-β-sitosterone (1). In addition, the compound showed potential toxicity to 293A cells of human. Conclusion: Further analysis finds that the new compound may be an artifact which is produced by exposing a steroid to strong sunlight in chloroform for a long time, and the reaction mechanism is speculated as the radical substitution reactions induced by strong light.