Biotransformation of cholesterol to diosgenin by freely suspended and immobilised cells of Dioscorea bulbifera L.

The cell suspension cultures, established from the friable callus which was risen from the nodal segments of Dioscorea bulbifera L. in Murashige-Skoog (MS) medium supplemented with indole-3-butryic acid (20 mg L- 1), was examined for cell growth in MS medium fed with cholesterol (50 mg L- 1 and 100 mg L- 1) after 8, 10, 12, 14, 16, and 18 days of culture. The growth index of the cell suspension culture on the 8th day was 1.2 and gradually inclined to 1.9 on the 16th day and remained the same at the 18th day. There is no marked difference in the cell growth of cholesterol-treated and control cell suspension culture. The maximum accumulation of diosgenin was noticed on the 14th day in control and cholesterol-treated cell suspension culture and immobilised cell cultures. The highest concentration of diosgenin, 2.94% and 2.14% dry weight, was obtained in immobilised cell culture and cell suspension culture treated with 100 mg L- 1 cholesterol, respectively

Biotransformation of Ferulic Acid to Vanillin by Locally Isolated Bacterial Cultures

610-612The biotransformation of ferulic acid to vanillin was carried out using locally isolated bacterial cultures from manure, paddy straw and garbage samples which include Pseudomonas sp. Pseudomonas sp. was enriched with the ferulic acid thrice and subsequently named as EF1, EF2 and EF3• EF3 produced maximum vanillin (850 g/100mg culture), followed by EF2 (842 g/100mg culture), manure isolate MAMWR (B) (598 g/100mgculture), EF1 (474 g/100mg culture) and Pseudomonas sp. (230 g/100mg culture). Garbage isolate GRMWSR (B) produced very insignificant amount (1.13 g/100mgculture) of vanillin

<i>In vitro </i>Shoot Regeneration from Leaf and Nodal Explants of <i>Enicostemma</i> <i>hyssopifolium </i>(Willd.) Verd.— A Vulnerable Medicinal Plant

401-404Enicostemma hyssopifolium (Willd.) Verd. plants were established in aseptic cultures from surface sterilized leaf and single node stem segments. Multiple shoots were elicited from leaf explants on MS medium supplemented with BAP (1.5 mg1-1) and IAA (0.5 mg 1-1), while from nodal explants on BAP (1.0 mg 1-1) and IAA (0.5 mg1-1). Maximum shoot proliferation and elongation was established in shoots derived from leaf explants on MS medium supplemented with KN (1.0 mg 1-1) and BAP (1.0 mg 1-1), while in shoots derived from nodal explant it was on MS supplemented with KN (1.0 mg 1-1) and BAP (0.5 mg 1-1). Plantlets were rooted on 1/2 strength MS medium supplemented with IAA (1.0 mg 1-1). The in vitro raised plantlets were acclimatized in green-house and successfully transplanted to the nursery

A modified freeze–thaw method for efficient transformation of Agrobacterium tumefaciens

There is a great potential for genetic manipulation of crop and medicinal plants to enhance productivity through increasing pest and microbial disease resistance and environmental stress tolerance, and also for studying gene function and regulation of physiological and developmental processes$^1$. Transgenic plants that transmit the introduced trait to progeny generations are produced using various DNA delivery methods such as particle acceleration$^2$, electroporation$^3$ and polyethylene glycol permeabilization of protoplasts$^4$. However, most commonly used method for obtaining transgenic plants is by the Agrobacterium tumefaciens-mediated transformation$^{5,6}$. Agrobacterium can transfer DNA to a remarkably broad group of organisms – numerous dicot and monocot angiosperm species$^5$, gymnosperms$^6$ and fungi, including yeast$^7$, ascomycetes$^8$ and basidiomycetes$^9$. Recently, Agrobacterium was reported to transfer DNA to human cells$^{10}$

<i style="">In vitro </i>shoot regeneration from leaf and nodal explants of <i style="">Vernonia cinerea</i> (L.) Less

418-420Multiple shoots were obtained from leaf and nodal explants of Vernonia cinerea on MS media supplemented with different concentrations of BAP. Maximum numbers of shoots were obtained from leaf and nodal explants at 3.0 mg L-1 and 2.5 mg L-1 concentrations of BAP, respectively. Shoot multiplication and their development was better on MS medium supplemented with BAP (2.0 mg L-1) along with NAA (1.5 mg L-1) for both the explants. Rhizogenesis was observed when in vitro shoots were subcultured in half strength MS medium containing IAA (1.5 mg L-1). The in vitro raised plantlets were acclimatized and established successfully in the field