16 research outputs found
Ophiorrhiza, a promising herbaceous source of the anticancer compound camptothecin
Camptothecin is an important source for the synthesis of some of the major anti-cancer agents such as irinotecan and topotecan. Traditional source of camptothecin are prominently woody plants such as Camptotheca acuminata Decne. and Nothopodytes nimmoniana (Graham) Mabb., and the increasing demand for camptothecin leads to the level of threatening their existence. Ophiorrhiza species composed of herbaceous plants with quick growth characteristics which are reported as alternative source of camptothecin. The present review focus on taxonomical status, traditional uses, biological activities and phytochemical constituents with a special attention in bioproduction of camptothecin from Ophiorrhiza species and its future prospects
Diversity analysis of released varieties of Indian cardamom using ISSR markers reveal narrowing genetic base
311-322Elettaria cardamomum Maton the small cardamom of commerce is a monotypic genus in India under the family Zingiberaceae. Genetic diversity studies using inter simple sequence repeat (ISSR) markers were conducted on a total of 13 released varieties of cardamom including selections and hybrids from different research stations in South India along with a popular variety Njallani and a wild relative Aframomum sps as checks. ISSR markers however, revealed relatively high level of genetic redundancy among the tested varieties with the exception of a few. Nonetheless, unweighted pair group method of arithmetic average (UPGMA) based cluster analysis of the similarity matrix differentiated all the varieties tested with the exception of two and segregated the wild relative Aframomum. Considerable reduction of polymorphism percentage was observed on exclusion of Aframomum while studying ISSR polymorphism which could be an indicator of the narrowing genetic base in the released varieties. Morphological data were compiled based on International Plant Genetic Resources Institute (IPGRI) cardamom descriptor and revealed moderate variability among the varieties. The results highlighted the requirement of molecular characterization of unutilized germplasm accessions, related wild species, and exotic relatives using specific molecular markers to help refine breeding efforts and introgression of new alleles for further improvement and enhancement of genetic base of cultivated cardamom
Soft Confinement Effects on Dynamics of Hydrated Gelatin
Soft materials under geometrical
confinement are ubiquitous and
known to exhibit fascinating properties, sometimes even antagonistic
to their bulk counterpart. Here, we explore the structural relaxation
dynamics (α-relaxation) of the biopolymer gelatin dissolved
in water (bulk form) and under soft spatial confinement using dielectric
relaxation spectroscopy over a wide frequency range starting from
1 Hz up to 2 GHz. The gelatin–water mixture (hydrated gelatin)
is geometrically restricted by the soft fluctuating surfactant monolayer
of water–AOT (sodium bis(2-ethylhexyl)sulfosuccinate)-<i>n</i>-decane reverse microemulsions (MEs), where the core size
of microemulsion droplets varies from 3.7 to 5.0 nm. The stability
of the droplet phase of microemulsion after the incorporation of gelatin
is confirmed by the small-angle neutron scattering (SANS) experiment.
Notably, the hydrated gelatin in soft confinement exhibits faster
relaxation dynamics in comparison to its bulk counterpart, and it
further gets accelerated with reduction in the confining volume. Our
combined results imply that the properties of confining boundary strongly
influence the dynamics of the enclosed material