Commiphora wightii (Arnott.) Bhandari in the Indian Desert: Biology, Distribution and Threat Status

Rising trade, declining stocks: The global gugul (Commiphora wightii) trade

ETHNOPHARMACOLOGICAL RELEVANCE

Commiphora wightii is exploited in India and Pakistan for an oleo-resin (gum guggul) traditionally used in Ayurvedic, Siddha and Unani medical systems. Processed C. wightii oleo-resin products are exported from India to 42 countries, including re-export to Pakistan, for anti-inflammatory use and as an anti-inflammatory and an anti-obesity treatment considered to lower cholesterol and lipid levels. The C. wightii export trade has particular relevance to the European Union because Belgium, France, Germany, Hungary, Italy, the Netherlands, and United Kingdom are importing countries. Demand and prices for C. wightii oleo-resin are increasing and wild stocks of C. wightii are in decline. The overexploitation of C. wightii after tapping for its commercially valuable oleo-resin is not a new problem, however, but one that has existed for over 50 years. Lopping and chopping trees to extract C. wightii oleo-resin has had a devastating impact on C. wightii populations since the 1960's.

AIM OF THE STUDY

The aim of this study was to review the sustainability of the global trade in C. wightii oleo-resin. This included reviewing studies on resin tapping methods and the impacts of wild harvest on C. wightii populations in India and Pakistan.

MATERIALS AND METHODS

Firstly, we reviewed studies on impacts of C. wightii oleo-resin harvest and on the policy responses taken in relation to harvest and trade in C. wightii oleo-resin. Secondly, we reviewed studies on C. wightii cultivation. Thirdly, global trade data for C. wightii were analyzed.

RESULTS AND CONCLUSIONS

Destructive harvest to obtain the gum is the major threat facing this species. C. wightii populations are also fragmented by habitat loss through clearing for farming. Cutting and lopping in order to extract the medicinal gum are a major threat to C. wightii populations, as is poor recruitment due to grazing by livestock. As a result of over-exploitation, C. wightii oleo-resin production has declined in India. In Gujarat, a key production area, the decline over a 50-year period has been from 30 t in 1963, to 2.42 t in 1999 to 1.6 t in 2013. Consequently, large quantities of C. wightii oleo-resin (around 505 t/year) are imported into India from Pakistan. An estimated 193 t/year of crude gum equivalent is exported from India in the form of processed products. With remaining populations in decline due to commercial exploitation for international trade, a range of policy options (such as CITES Appendix II listing) and practical conservation actions (such as cultivation) need to be considered.

Quantitative determination of guggulsterone in existing natural populations of Commiphora wightii (Arn.) Bhandari for identification of germplasm having higher guggulsterone content

Guggulsterone is an aromatic steroidal ketonic compound obtained from vertical rein ducts and canals of bark of Commiphora wightii (Arn.) Bhandari (Family - Burseraceae). Owing to its multifarious medicinal and therapeutic values as well as its various other significant bioactivities, guggulsterone has high demand in pharmaceutical, perfumery and incense industries. More and more pharmaceutical and perfumery industries are showing interest in guggulsterone, therefore, there is a need for its quantitative determination in existing natural populations of C. wightii. Identification of elite germplasm having higher guggulsterone content can be multiplied through conventional or biotechnological means. In the present study an effort was made to estimate two isoforms of guggulsterone i.e. E and Z guggulsterone in raw exudates of 75 accessions of C. wightii collected from three states of North-western India viz. Rajasthan (19 districts), Haryana (4 districts) and Gujarat (3 districts). Extracted steroid rich fraction from stem samples was fractionated using reverse-phase preparative High Performance Liquid Chromatography (HPLC) coupled with UV/VIS detector operating at wavelength of 250 nm. HPLC analysis of stem samples of wild as well as cultivated plants showed that the concentration of E and Z isomers as well as total guggulsterone was highest in Rajasthan, as compared to Haryana and Gujarat states. Highest concentration of E guggulsterone (487.45 μg/g) and Z guggulsterone (487.68 μg/g) was found in samples collected from Devikot (Jaisalmer) and Palana (Bikaner) respectively, the two hyper-arid regions of Rajasthan, India. Quantitative assay was presented on the basis of calibration curve obtained from a mixture of standard E and Z guggulsterones with different validatory parameters including linearity, selectivity and specificity, accuracy, auto-injector, flow-rate, recoveries, limit of detection and limit of quantification (as per norms of International conference of Hormonization). Present findings revealed the role of environmental factors on biosynthesis of guggulsterone isomers under natural conditions.