In vitro production and chemical characterization of St. John’s wort (Hypericum perforatum L. cv ‘New Stem’)

Antibacterial activity of leaves and inter-nodal callus extracts of Mentha arvensis L

This report describes Agrobacterium tumefaciens-mediated transformation of Withania somnifera—an important Indian medicinal plant. A. tumefaciens strain LBA4404, containing the binary vector pIG121Hm was used for transformation, along with the gusA reporter gene with intron under the transcriptional control of the Cauliflower Mosaic Virus (CaMV) 35S promoter. The leaf segments from two-and-a-half-month-old green house-grown seedlings were more efficient in transformation, as compared to those from the in vitro-grown shoots. Second expanded leaf from the shoot tip gave the highest transient transformation efficiency. Selection of transgenic shoots was done in the presence of 50 mg l−1 kanamycin. Polymerase chain reaction analysis of T0 transgenic plants showed the presence of gusA and nptII genes. The expression of these transgenes in T1 progeny was confirmed by RT-PCR. The integration of gusA gene was confirmed by Southern blot analysis. The transformation efficiency was found to be 1.67%.

Agrobacterium tumefaciens-mediated transformation of Withania somnifera (L.) Dunal: an important medicinal plant

Effecient multiplication of Withania somnifera was achieved through culture of shoots tips of mature plants on Murashige and Skoog (MS), Schenk and Hildebrandt (SH) and Gamborg (B5) media. However, MS medium was found superior to SH and B5. MS medium supplemented with BAP+IAA (each at 2.0 mg/L) was optimal for induction of shoot buds; whereas, MS supplemented with 0.3 mg/L GA3 was the most suitable for shoot elongation. Elongated shoots were rooted on half strength MS containing with 2.0 mg/L IBA. The rooted plantlets were successfully established in field.

http://nopr.niscair.res.in/bitstream/123456789/5023/1/IJBT%206%281%29%20125-127.pdf

Direct regeneration from apical bud explants of Withania somnifera Dunal

Withania (Family: Solanaceae) is a highly acclaimed genus in the Indian Ayurvedic system of medicine. In Ayurveda, Withania is known to promote physical and mental health and used to treat almost all the disorders that affect human health. Withania somnifera andWithania coagulans are the two most esteemed species of this genus having high medicinal significance. These species are natural source of withanolides (steroidal lactones) which are used as ingredients in many formulations prescribed for a variety of diseases. Many pharmacological studies have been conducted to investigate the properties of Withania as a multi-purpose medicinal agent. Advances in biotechnology, especially in vitro culture techniques, molecular biology and metabolite profiling provided new insights for conservation and management of plant genetic resources and better harvesting of drugs from medicinal plants. This review presents a consolidated account of the phytochemistry, pharmacology and biotechnology involving in vitro propagation, genetic transformation and metabolite profiling in W. somnifera and W. coagulans.

	 

	Key words: Withania, phytochemistry, pharmacology, withanolides, micropropagation, metabolite profiling.

Phytochemistry, pharmacology, and biotechnology of Withania somnifera and Withania coagulans: A review

The development of stem callus mediated plant regeneration system for Withania somnifera is described. Maximum callus proliferation was obtained on Murashige and Skoog medium supplemented with 2.26 μM 2,4-D. Three-week-old, white, friable callus was used for shoot regeneration. The maximum shoot regeneration (6.2 ± 0.34 shoots/explant) was achieved in four weeks when callus was cultured on MS medium fortified with 4.44 μM BA and 0.57 μM IAA. Regenerated shoots were excised and multiplied (8.4 ± 0.43 shoots/explant) on MS medium supplemented with 4.44 μM of BA. Multiple shoots were divided into single shoots and were rooted (5.1 ± 0.49 rootlets/shoot) on half strength MS medium supplemented with 9.84 μM of IBA. After a hardening phase of 3 weeks the plantlets were transferred to the field.

R. Elango Mathavan

Papers

Regeneration of indian ginseng plantlets from stem callus