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The effect of copper sulphate on differentiation and elongation of shoot buds from cotyledonary explants of Capsicum annuum L. cv X-235 was investigated. Shoot buds were induced on medium supplemented with 22.2 lM BAP and 14.7 lM PAA. Elongation of shoot buds was obtained on MS medium containing 13.3 lM BAP + 0.58 lM GA 3 . Both shoot induction and elongation media were supplemented with different levels of CuSO 4 (0-5 lM). The levels of CuSO 4 in the induction as well as elongation medium highly influenced the shoot bud formation and their subsequent elongation. Highest number of shoot buds per explant was obtained when the concentration of CuSO 4 was increased 30 times to the normal MS level. Shoot buds formation frequency i.e., the number of shoots formed per explant was increased two fold as compared to those formed on control. Elongation both in terms of percentage and length of shoots was better than that on control. Healthy elongated shoots were rooted on MS medium supplemented with 5.7 lM IAA. Rooted plantlets were transferred to field conditions.

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Portulaca grandiflora, an important medicinal plant was found to show the incidence of shoot tip necrosis (STN) in shoot cultures obtained from nodal explants in Murashige and Skoog (MS) medium with 3% sucrose along with 8 µM Kinetin and 4 µM BAP. This physiological disorder is primarily due to the deficiency of calcium and boron content in the medium. Thus in the present work varying concentration of boron which was used in the form of boric acid (0.1-0.4 mM), calcium gluconate (3-30 mM) and calcium chloride (3-30 mM) were incorporated in MS medium and its effect on STN was evaluated. The observations revealed that 18 mM calcium chloride was the optimum concentration for lowering STN in shoot cultures to 40% after four weeks.

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The cotyledonary node and nodal explants Stereospermum suaveolens DC. were cultured on Woody Plant medium (WPM) supplemented with individual BAP 2 -25 μM), Kn (2 -25 μM) and TDZ (0.1 -2 μM. Observations revealed that in both cotyledonary node and nodal explants, lower concentrations of cytokinins (BAP/Kn/TDZ) were effective in inducing proliferation response. The axillary bud of both the explants proliferated into single shoots which were further subcultured on fresh medium with respective concentrations for shoot multiplication. It was observed that multiple shoots developed only in presence of Kn (8 μM) in both the explants but the shoots developed from nodal explants were strong and healthy with average shoot number reaching to 3.8 ± 0.6 and length 5.4 ± 0.4 cm by the end of third passage. Rooting (100%) was achieved in microshoots when transferred to half strength WPM liquid medium supplemented with IBA (2 μM). The plantlets were transferred to different substrates for acclimatization.

Miconazole, a potent antifungal agent, labilizes rat liver lysosomes. Its labilizing effect is followed by measuring the release of lysosomal hydrolases, namely, acid phosphatase, (-glucuronidase, and arylsulfatase A. The effect of miconazole is concentration dependent in the range of 10-5 to 1.2 x 10-4 M. However, at higher concentrations, miconazole inhibits enzyme release but does not inhibit enzyme activities per se. The effect of miconazole depends on the drug/ lysosome ratio and is influenced by the pH of the incubation media, being minimal at alkaline pH. Membrane-active drugs such as nystatin, 2-phenethylalcohol, hexachlorophene, and digitonin have been compared with miconazole for their lysosome-labilizing action. The effect of miconazole on the lysosomal membrane is confirmed by a decrease in turbidity of the lysosomal suspension.Miconazole {1-[2,4-dichloro-,8-(2,4-dichlorobenzyloxy)-phenethyl]imidazole nitrate} has a broad spectrum of antimicrobial activity against pathogenic and nonpathogenic yeasts, dermatophytes, numerous saprophytic fungi, and gram-positive bacteria (13,25,31). Chemotherapeutic activity of miconazole as a topical applicant is well documented in the treatment of skin and nail infections and vaginal candidiasis (2,5,14,29,32). Studies on the mechanism of biological action of miconazole have been recently reported (9, 10, 28, 33; K. H. Sreedhara Swamy, M. Sirsi, and G. Ramananda Rao, Biochem. Pharmacol., in press). The drug induces leakage of intracellular materials from cells of Candida albicans (28), and at low concentrations it selectively inhibits the uptake of purines and glutamine into these cells (33). Electron microscopic examination of cells of C. albicans exposed to miconazole revealed that the earliest drug-induced alterations are seen at the plasma membrane (9, 10). Further, miconazole has been shown to induce hemolysis of mammalian erythrocytes and binds strongly to erythrocyte membrane lipoproteins (Sreedhara Swamy et al., in press). These investigations clearly indicate that the paramount feature of the biological action of miconazole is its interaction with cell membrane of sensitive organisms, resulting in the impairment of membrane function and eventually cell death.In an attempt to delineate the mode of action of miconazole on cellular and organellar membranes and to obtain a more comprehensive view of biological action, we have carried out studies on the interaction of miconazole with rat liver lysosomes. The present paper describes the effect of miconazole on the integrity of lysosomal membrane, providing further evidence that miconazole interacts with biological systems by impairing membrane function. MATERIALS AND METHODSChemicals. Miconazole nitrate was a gift sample from Ethnor Ltd., Bombay, India. Hexachlorophene, digitonin, 2-phenethylalcohol, p-nitrophenylphosphate, p-nitrocatechol sulfate, phenolphthalein-,-nglucuronide, Triton X-100, and tris(hydroxymethyl)-aminomethane (Trizma base) were purchased from Sigma Chemical Co., St. Louis, Mo. Nystatin was kin...