Studies on leaf epidermal micromorphology, wood element characters and phytochemical screening of three medicinal plants of Convolvulaceae

Abstract

The scientific evaluation of ethnomedicinally important plants is now being done thoroughly covering various aspects of study like efficacy of the crude drugs, chemistry of active principles, different pharmacognostic parameters, etc. The use of micromorphology and anatomy is now a recognised tool in the field of plant systematics. Therefore, in this investigation the micromorphology of leaf epidermis, stem xylem element characters and phytochemical screening of three ethnomedicinally important members of the family Convolvulaceae namely Evolvulus alsinoides, Evolvulus nummularius and Ipomoea cairica have been studied. The epidermal cells are found to be irregular in shape and the outlines of the cells are wavy in every species. Stomata are amphistomatic and mainly of paracytic type except in Evolvulus nummularius. Trichomes are glandular and non-glandular, unicellular or multicellular, straight or curved. The range of stomatal index varies from 11.40 to 20.00. Palisade ratio ranges from 6.2 to 9.8. The vessel element length ranges from 60.71 um to 357.10 um and the diameter varies from 21.78 um to 66.06 um. Perforation plate is simple and transverse or obliquely placed. Fibres are typical libriform, very long and diameter ranges from 10.71 um to 16.78 um. In every case, tracheids are long with spiral to condensed spiral type of sidewall thickening and diameter is from 07.14 um to 16.07 um. The active compounds are identified by the chemical colour reaction tests belonging to the phytochemical groups of amino acids, alkaloids, reducing sugars, flavonoids, saponins, steroids and triterpenoids, tannins, etc. The findings will be a useful marker for identification of the crude drugs obtained from the selected taxa. The purpose of the study is to know the leaf epidermal micromorphology, wood element characters and phytochemical screening of three ethnomedicinally important plants of the family Convolvulaceae as it has not been properly worked out. These micromorphological features and phytochemical screening will be very helpful in proper identification of respective crude drugs obtained from these three members of Convolvulaceae and also be used in detection of drug adulterants. Thus, it will be a tool in maintaining the quality of the drug obtained from these three plant species.