Pandey Devendra Kumar, Kaur Prabhjot, Kumar Vijay, Banik R M, Malik Tabarak, Dey Abhijit
Department of Biotechnology, School of Biotechnology and Biosciences, Lovely Professional University, Phagwara, Punjab, 144411, India.
School of Biochemical Engineering, Indian Institute of Technology BHU, Varanasi, India.
BMC Plant Biol. 2021 Feb 5;21(1):77. doi: 10.1186/s12870-021-02843-8.
Gloriosa superba L. (Colchicaceae) is a high-value medicinal plant indigenous to Africa and Southeast Asia. Its therapeutic benefits are well-established in traditional medicines including Ayurveda. It is well known for its natural bioactive compound colchicine which exhibits a wide range of pharmacological activities i.e. rheumatism, gout and was also introduced into clinical practices. The increasing demand as well as its illegal harvesting has brought this valuable plant under threatened category.
The present investigation describes a microwave assisted extraction (MAE) strategy coupled with a densitometric-high performance thin layer chromatographic (HPTLC) methodology for the analysis of colchicine from 32 different populations of G. superba. A Box-Behnken statistical design (3 level factor) has been employed to optimize MAE, in which power of microwave, time of irradiation, aqueous ethanol and pH were used as independent variables whereas colchicine was used as the dependent variables. Chromatography was carried out on Silica gel 60 F TLC plates with toluene: methanol, 85:15 (v/v) being used as solvent system. Densitometric measurement was performed at λ=254 nm following post-derivatization (10% methanolic sulphuric acid).
Optimal conditions for extraction to obtain the maximum colchicine yield was found to be 7.51 mg g which was very close to be predicted response 7.48 mg g by maintaining microwave power (460 W), irradiation time (6.4 min), aqueous ethanol-30, pH -3. Colchicine content ranged between 2.12-7.58 mg g among 32 G. superba populations in which only three chemotypes viz. GS- 1, GS- 3, and GS- 2 collected from West Bengal and Sikkim, respectively exhibited maximum yield of colchicine.
Therefore, this newly developed optimized MAE coupled with HPTLC densitometry methodology not only quantifies colchicine in order to identify elite chemotypes of G. superba, but it also encourages in selecting high yielding populations of the plants for industrial use and economic boost for the farmers. This validated, simple and reproducible HPTLC protocol is being used for the first time to estimate colchicine from natural populations of G. superba obtained from 32 different geographical regions of India.
秋水仙（秋水仙科）是一种原产于非洲和东南亚的高价值药用植物。其治疗功效在包括阿育吠陀医学在内的传统医学中已得到充分证实。它以其天然生物活性化合物秋水仙碱而闻名，秋水仙碱具有广泛的药理活性，如治疗风湿、痛风，并且已被引入临床实践。需求的增加以及非法采摘已使这种珍贵植物处于濒危类别。
本研究描述了一种微波辅助萃取（MAE）策略，并结合密度测定 - 高效薄层色谱（HPTLC）方法，用于分析来自32个不同秋水仙种群的秋水仙碱。采用Box - Behnken统计设计（三水平因子）来优化MAE，其中微波功率、辐照时间、乙醇水溶液和pH值用作自变量，而秋水仙碱用作因变量。在硅胶60F TLC板上进行色谱分析，以甲苯：甲醇，85:15（v/v）作为溶剂系统。在10%甲醇硫酸后衍生化后，于λ = 254nm处进行密度测定。
发现获得最大秋水仙碱产量的最佳萃取条件为7.51mg/g，通过保持微波功率（460W）、辐照时间（6.4分钟）、乙醇水溶液 - 30、pH - 3，该值非常接近预测响应值7.48mg/g。在32个秋水仙种群中，秋水仙碱含量在2.12 - 7.58mg/g之间，其中仅从西孟加拉邦和锡金分别采集的三种化学型，即GS - 1、GS - 3和GS - 2表现出最大的秋水仙碱产量。
因此，这种新开发的优化MAE与HPTLC密度测定方法不仅用于定量秋水仙碱以鉴定秋水仙的优良化学型，还有助于选择高产植物种群用于工业用途并为农民带来经济增长。这种经过验证、简单且可重复的HPTLC方案首次用于估计从印度32个不同地理区域获得的秋水仙自然种群中的秋水仙碱。
