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101.
Deepika Sharma Rupam Kapoor Ashok K. Bhatnagar 《World journal of microbiology & biotechnology》2008,24(3):395-400
Curculigo orchioides Gaertn. (family Hypoxidaceae) is an endangered anticarcinogenic and aphrodisiac herb, native of India. This study reports
the effect of three arbuscular mycorrhizal (AM) fungal inocula on post-transplanting performance of ‘in vitro’ raised C. orchioides plantlets. The three AM fungal inocula consisted of two monospecific cultures of Glomus geosporum and G. microcarpum and one crude consortium of AM fungal spores isolated from rhizosphere soil of C. orchioides growing in natural habitat. Complete plantlets of C. orchioides were raised by direct organogenesis of leaf explants on half strength Murashige and Skoog’s medium devoid of any growth hormone.
C. orchioides plantlets responded significantly different to all three mycorrhizal treatments. Mycorrhization enhanced the survival rate
of C. orchioides plantlets to 100%. The inoculated plantlets fared significantly better than the uninoculated ones in terms of biomass production
and number of leaves and roots per plant. Mycorrhizal plantlets exhibited higher concentrations of photosynthetic pigments
as well as minerals P, Mg, Cu, Zn, Mn and Fe in both shoots and roots. Among the three inocula tested, plantlets inoculated
with the mixed consortium of AM fungi consistently performed better in terms of the parameters evaluated. The study suggests
use of mixed consortium of AM fungi over monospecific cultures for the sustainable cultivation and conservation of endangered
medicinal plant: Curculigo orchioides. 相似文献
102.
Yu Jiujiang Chang Perng-Kuang Bhatnagar Deepak Cleveland Thomas E. 《Mycopathologia》2003,156(3):227-234
103.
The objective of the present communication is to address the issues concerning reversal of fluoride induced cell injury and disease (i.e. fluorosis) through the elimination of fluoride and consumption of a diet containing essential nutrients and antioxidants. Humans afflicted with fluorosis, as a result of consuming fluoride contaminated water or food, have been investigated. Hospital based diagnostic procedure for early detection of fluorosis, through retrieval of history, clinical complaints, testing of blood, urine and drinking water for fluoride using ion selective electrode technology, along with X-ray of the forearm have been carried out. Confirmed cases of fluorosis were introduced to an intervention protocol consisting of (1) provision of safe drinking water with fluoride levels less than 1 mg/L and (2) counselling on nutritional supplementation with focus on adequate intake of calcium, vitamins C, E and antioxidants. The patients were monitored at frequent intervals up to one year and the results are reported. With a standardized early diagnosis, elimination of fluoride intake and supplementation of a diet rich in essential nutrients and antioxidants, we have shown that the fluorosis can be reversed. 相似文献
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107.
Primary structure of the deoxyguanosine triphosphate triphosphohydrolase-encoding gene (dgt) of Escherichia coli 总被引:1,自引:0,他引:1
The complete nucleotide sequence has been determined for a 2027-bp region that encompasses the structural gene (dgt) encoding deoxyguanosine triphosphate triphosphohydrolase (dGTPase) from Escherichia coli. The gene resides between the htrA and dapD loci at 3.75-3.8' on the bacterial chromosome. Using homologous recombination in a recD recipient, a dgt- bacterial strain was constructed that was deficient in producing functional dGTPase. Comparison of dGTP pools in this and other strains revealed that dGTPase synthesized in vivo does to some degree modulate the level of dGTP in the bacterial cell, yet the magnitude of this modulation may be insufficient to explain the physiological function of dGTPase. 相似文献
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109.
R Z Hawirko P K Bhatnagar K L Chung C T Chow 《Canadian journal of microbiology》1977,23(12):1706-1713
The effect of rifampicin on the developmental phases of germinating spores of Clostridium botulinum, MSp+, has been studied. At sublethal concentrations of rifampicin (0.05 ng/ml) the time periods required for outgrowth and vegetative growth was significantly prolonged because of the inhibition of RNA and protein synthesis. However, rifampicin had essentially no effect on DNA synthesis or on subsequent spore formation. Chemical analyses showed that the amount of protein present in vegetative cells of the rifampicin-treated cultures was twice as great as in the untreated cultures but the total protein content of endospores was the same in both cases. It was revealed in ultrastructural studies of rifampicin (0.1 ng/ml) treated cultures, examined after 22 h, that septum formation and normal cell division of the emerging cell was blocked and a few cells showed constriction which produced one normal and one protoplast-like daughter cell. 相似文献
110.