ABSTRACT
An in vitro method of multiple shoot induction and plant regeneration in Psophocarpus tetragonolobus (L.) DC was developed. Cotyledons, hypocotyls, epicotyls, internodal and young seedling leaves were used as explants. MS media supplemented with various concentrations of either thidiazuron (TDZ) or N6-benzylaminopurine (BAP) along with NAA or IAA combinations were used to determine their influence on multiple shoot induction. MS media supplemented with TDZ induced direct shoot regeneration when epicotyls and internodal segments were used as explants. TDZ at 3 mg L(-1) induced highest rate (89.2 ± 3.28%) of regeneration with (13.4 ± 2.04) shoots per explant. MS media supplemented with BAP in combination with NAA or IAA induced callus mediated regeneration when cotyledons and hypocotyls were used as explants. BAP (2.5 mg L(-1)) and IAA (0.2 mg L(-1)) induced highest rate (100 ± 2.66%) of regeneration with (23.2 ± 2.66) shoots per explant. Mature plants produced from regenerated shoots were transferred successfully to the greenhouse. In a comparative study, the phenolics contents of various parts of greenhouse-grown plants with that of in vitro-raised plants showed significant variations.
Subject(s)
Fabaceae/growth & development , Fabaceae/metabolism , Phenols/metabolism , Plant Shoots/physiology , Regeneration , Tissue Culture Techniques/methods , Benzyl Compounds/pharmacology , Cotyledon/drug effects , Cotyledon/physiology , Fabaceae/drug effects , Flavonoids/metabolism , Hypocotyl/drug effects , Hypocotyl/physiology , Indoleacetic Acids/pharmacology , Naphthaleneacetic Acids/pharmacology , Plant Leaves/drug effects , Plant Leaves/physiology , Plant Roots/drug effects , Plant Roots/metabolism , Plant Shoots/drug effects , Plant Stems/drug effects , Plant Stems/metabolism , Purines/pharmacology , Regeneration/drug effects , Secondary Metabolism/drug effectsABSTRACT
A gene from Withania somnifera (winter cherry), encoding a highly stable chloroplastic Cu/Zn superoxide dismutase (SOD), was cloned and expressed in Escherichia coli. The recombinant enzyme (specific activity of ~4,200 U mg(-1)) was purified and characterized. It retained ~90 and ~70% residual activities after 1 h at 80 and 95 °C, respectively. At 95 °C, thermal inactivation rate constant (K (d)) of the enzyme was 2.46 × 10(-3) min(-1) and half-life of heat inactivation was 4.68 h. The enzyme was stable against a broad pH range (2.5-11.0). It also showed a high degree of resistance to detergent, ethanol and protease digestion. This recombinant Cu/Zn SOD could therefore have useful applications.
