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21.
P.S.M. Krishna G. Venkateswarlu L.V. Rao 《World journal of microbiology & biotechnology》1998,14(5):689-691
The fermentative production of rifamycin by Amycolatopsis mediterranei (MTCC17) has been studied. Both qualitative and quantitative aspects of the fermentation were determined by optimizing cultural conditions and medium design to improve the production of rifamycin. A pH value of 7.0, a temperature of 26°C, an aeration rate of 250rev/min for a 50ml volume, a level of inoculum of 10% grown aeration for 48h and a fermentation period of 11days were found to be optimum. Among the nitrogen sources, and culture conditions, peanut meal and aeration were found to be critical for rifamycin production respectively. The above mentioned exercise increased the yields of rifamycin from 350mg/l to 2000mg/l. 相似文献
22.
Divakara S. S. M. Uppu Goutham B. Manjunath Venkateswarlu Yarlagadda Jyothi E. Kaviyil Raju Ravikumar Krishnamoorthy Paramanandham Bibek R. Shome Jayanta Haldar 《PloS one》2015,10(3)
Gram-negative ‘superbugs’ such as New Delhi metallo-beta-lactamase-1 (bla
NDM-1) producing pathogens have become world’s major public health threats. Development of molecular strategies that can rehabilitate the ‘old antibiotics’ and halt the antibiotic resistance is a promising approach to target them. We report membrane-active macromolecules (MAMs) that restore the antibacterial efficacy (enhancement by >80-1250 fold) of tetracycline antibiotics towards bla
NDM-1
Klebsiella pneumonia and bla
NDM-1
Escherichia coli clinical isolates. Organismic studies showed that bacteria had an increased and faster uptake of tetracycline in the presence of MAMs which is attributed to the mechanism of re-sensitization. Moreover, bacteria did not develop resistance to MAMs and MAMs stalled the development of bacterial resistance to tetracycline. MAMs displayed membrane-active properties such as dissipation of membrane potential and membrane-permeabilization that enabled higher uptake of tetracycline in bacteria. In-vivo toxicity studies displayed good safety profiles and preliminary in-vivo antibacterial efficacy studies showed that mice treated with MAMs in combination with antibiotics had significantly decreased bacterial burden compared to the untreated mice. This report of re-instating the efficacy of the antibiotics towards bla
NDM-1 pathogens using membrane-active molecules advocates their potential for synergistic co-delivery of antibiotics to combat Gram-negative superbugs. 相似文献
23.
The purpose of this research was to study whether the bioavailability of lovastatin could be improved by administering lovastatin
solid lipid nanoparticles (SLN) duodenally to rats. Lovastatin SLN were developed using triglycerides by hot homogenization
followed by ultrasonication. Particle size and zeta potential were measured by photon correlation spectroscopy. The solid
state of the drug in the SLN and lipid modification were characterized. Bioavailability studies were conducted in male Wistar
rats after intraduodenal administration of lovastatin suspension and SLN. Stable lovastatin SLN having a mean size range of
60 to 119 nm and a zeta potential range of −16 to −21 mV were developed. More than 99% of the lovastatin was entrapped in
the SLN. Lovastatin was dispersed in an amorphous state, and triglycerides were in {ieE162-1} form in the SLN. In vitro stability
studies showed the slow release and stability of lovastatin SLN. The relative bioavailabilities of lovastatin and lovastatin
hydroxy acid of SLN were increased by ∼173% and 324%, respectively, compared with the reference lovastatin suspension.
Published: March 23, 2007 相似文献
24.
G. R. Rao Arun K. Shanker I. Srinivas G. R. Korwar B. Venkateswarlu 《Trees - Structure and Function》2011,25(4):725-734
A thorough and extensive wild germplasm exploration survey was undertaken and 50 high yielding candidate plus trees (CPTs)
of Pongamia pinnata (L.) Pierre from different locations from a latitudinal and longitudinal spread between 12°41′ and 22°E longitude and 77°
and 84°40′N latitude covering 11 locations in an area spread of 150,000 km2 were collected for evaluating genetic association and variability in seed and growth characters. There were significant differences
observed in seed morphology and oil content as was in plant height, and number of branches in the progeny trial. Plant height
and number of branches exhibited much higher values of both phenotypic and genotypic variance than observed in the seed characters.
Among seed characters oil content exhibited highest broad sense heritability of more than 93% followed by seed length (90.0%).
In contrast seed width showed the second highest genetic advance of 5.64% following the highest genetic advance of 10.15%
exhibited by oil content. Hierarchical clustering by Ward’s Minimum Variance Cluster Analysis method showed phylogeographic
patterns of genetic diversity. K means clustering revealed that trees from different geographic regions were grouped together
in a cluster and as were trees from the same geographical area placed in different clusters suggesting that geographical diversity
did not go hand in hand with genetic diversity. In addition clustering identified promising accessions with favourable traits
for future establishment of orchards. 相似文献
25.
A series of curcumin analogs (1-3, 5a-5t) was synthesized through the condensation of appropriately protected hydroxybenzaldehydes with acetylacetone, followed by deprotection. The antioxidant activity of these analogs was determined by superoxide free radical nitroblue tetrazolium and DPPH free radical scavenging methods and the polyhydroxycurcuminoids (5l-5s) displayed excellent antioxidant activity. These analogs showed cytotoxicity to lymphocytes and promising tumor-reducing activity on Dalton's lymphoma ascites tumor cells. 相似文献
26.
Das B Ramu R Venkateswarlu K Rao YK Reddy MR Ramakrishna KV Harakishore K Murty US 《化学与生物多样性》2006,3(2):175-179
Two new ent-clerodane-type diterpenoids, compounds 1 and 2, were isolated from the aerial parts of Pulicaria wightiana, together with three known constituents. Their structures were established based on spectroscopic data, and their antibacterial activities were evaluated (Table 2). 相似文献
27.
M. Maheswari N. Jyothi Lakshmi S. K. Yadav Y. Varalaxmi A. Vijaya Lakshmi M. Vanaja B. Venkateswarlu 《Biologia Plantarum》2006,50(4):741-744
An efficient and rapid regeneration protocol was developed using shoot apices from germinating seedlings of two cultivars
of sorghum, SPV-462 and M35-1, as explants. A vertical slit given from the base of each dissected apex enhanced the efficiency
of callusing response by two fold. MS medium containing 0.5 mg dm−3 each of 2,4-D and kinetin was most effective in producing friable and embryogenic calli. Scanning electron microscopy of
these calli detected somatic embryogenesis. Calli thus induced gave rise to approximately 42 green shoots per callus in both
the genotypes when transferred to regeneration medium containing 1.5 mg dm−3 kinetin. 相似文献
28.
Subrahmanyam D Sarma VM Venkateswarlu A Sastry TV Srinivas AS Krishna CV Deevi DS Kumar SA Babu MJ Damodaran NK 《Bioorganic & medicinal chemistry letters》2000,10(4):369-371
Several 5-substituted alkoxy 20(S)-camptothecin analogues having A- and B-ring substituents were prepared via semi-synthesis. Most of these compounds were found to exhibit potent anti-cancer activity based on their in vitro cytotoxicity data obtained against human tumor cell lines. 相似文献
29.
This work describes an alternative method for estimation of reaction rate of a biofilm process without using a model equation. A first principles model of the biofilm process is integrated with artificial neural networks to derive a hybrid mechanistic-neural network rate function model (HMNNRFM), and this combined model structure is used to estimate the complex kinetics of the biofilm process as a consequence of the validation of its steady state solution. The performance of the proposed methodology is studied with the aid of the experimental data of an anaerobic fixed bed biofilm reactor. The statistical significance of the method is also analyzed by means of the coefficient of determination (R2) and model efficiency (ME). The results demonstrate the effectiveness of HMNNRFM for estimating the complex kinetics of the biofilm process involved in the treatment of industry wastewater. 相似文献
30.
Purushotham Reddy S Chinnababu B Shekhar V Kumar Reddy D Bhanuprakash GV Velatoor LR Venkateswara Rao J Venkateswarlu Y 《Bioorganic & medicinal chemistry letters》2012,22(12):4182-4184
A simple, highly efficient and stereoselective synthetic route has been developed for synthesis of alpinoid-C (1) and its analogues (2, 3 and 4) from commercially available starting materials by using Wittig olefination, Sharpless asymmetric epoxidation, Grubbs cross metathesis as key steps. All the compounds showed moderate anti-proliferative activity against human leukemia/carcinoma (U-937, THP-1, COLO-205 and HepG2) and mouse melanoma (B16-F10) cancer cell lines. Compounds 3 and 4 are found to be most potent with an IC(50) of 7.53 μM and 32.26 μM on THP-1, 11.12 μM and 7.21 μM on COLO-205 cell lines, respectively. 相似文献