ABSTRACT
Northeast India represents a rich floristic wealth of India. Orchids form a very noticeable feature of this vegetation. Amongst orchids, the genus Dendrobium forms a very important group of plants which are used by the locals for the treatment of various ailments. A through literature survey revealed that there is a paucity of data on the phytochemical evaluation of Dendrobium species using analytical methods. The chromatographic technique such as HPTLC is reported to be useful for standardization of plant materials in terms of phytochemical markers and evaluation of their quality. Therefore, in this study, five different Dendrobium species have been evaluated and compared in terms of their marker content using validated HPTLC methods. All the samples analyzed were found to be a good source of β-sitosterol with maximum content in D. fimbriatum stem and minimum content in D. chrysanthum roots. D. nobile (roots and stem) and D. moschatum (stem) were also found to be a source of ursolic acid and lupeol, respectively. Thus, this work will contribute in the identification, quality evaluation and standardization of different Dendrobium species. On the basis of maximum bioactive marker content, specific part of Dendrobium species can be selected which may be supported by its efficacy.
ABSTRACT
A protocol has been devised for enhanced in vitro regeneration of critically endangered Mantisia spathulata Schult. and Mantisia wengeri Fischer. Highest Bud Forming Capacity (BFC) of 6.10 +/- 0.55 with an average of 19.93 +/- 3.19 roots was obtained for M. spathulata within 5-6 weeks in Murashige and Skoogs (MS) medium supplemented with a combination of 10.0 microM of N6-benzyladenine (BA) and 2.5 microM of alpha-naphtalene acetic acid (NAA). For M. wengeri, BFC of 7.82 +/- 0.73 and 20.86 +/- 1.65 roots was achieved in MS media supplemented with a combination of 5.0 microM BA and 2.5 microM of NAA RAPD markers were used to evaluate the genetic stability of in vitro raised hardened plantlets. Similarity coefficient among the regenerated plants ranged between 0.85-0.98 for M. spathulata and 0.83-0.98 for M. wengeri. Maximum of 88 and 90% genetic similarity were obtained between in vitro raised hardened plantlets and mother stock of M. spathulata and M. wengeri, respectively through RAPD analysis. The hardened plantlets after RAPD analysis on being transferred to soil of experimental garden showed no marked phenotypic variations in vegetative or floral characteristics.