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Vinod P. Shah Todd L. Cecil Srini V. Srinivasan Roger L. Williams 《The AAPS journal》2014,16(4):621-624
Principles of dissolution science have been applied to allow waiver of in vivo bioequivalence studies for oral immediate release solid dosage forms, providing certain stipulations are met. This approach reduces regulatory burden without sacrificing product quality and performance requirements that assure continuing equivalence. These principles are broadly applicable to other dosage forms and routes of administration. In this article, we postulate a further opportunity, which relies on a determination of “optimal performance” for nonsolution orally administered drug products. The determination can be applied to certain highly soluble and rapidly dissolving drug products without further study, paving the way possibly for even further reductions in regulatory burden. 相似文献
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T. Sindhu S. Rajamanikandan P. Srinivasan 《Indian journal of pharmaceutical sciences》2014,76(2):170-174
The present study was designed to evaluate the antioxidant and antibacterial activity of methanol extract of Kyllinga nemoralis. Six different in vitro antioxidant assays including 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, superoxide anion radical, hydrogen peroxide radical, ferric reducing antioxidant power assay and reducing power were carried out to ensure the scavenging effect of the plant on free radicals. In addition, total antioxidant capacity assay, total phenolic contents, tannins, flavonoids and flavonol contents of the plant were also analysed by the standard protocols. Kyllinga nemoralis exhibited high antioxidant activity on 2,2-diphenyl-1-picrylhydrazyl assay (IC50= 90 μg/ml), superoxide radical scavenging assay (IC50= 180 μg/ml) and hydrogen peroxide radical scavenging assay (IC50= 200 μg/ml), compared with standards. These observations provide comprehensible supporting evidence for the antioxidant potential of the plant extract. Reducing power (IC50= 213.16 μg/ml) and hydroxyl radical scavenging activity (IC50= 223 μg/ml) of the plant extract was remarkable. The methanol extract of K. nemoralis exhibited significant antimicrobial activity against Gram-positive human pathogenic bacteria. Standard in vitro antioxidant assays assessed the electron donating ability of the plant extract in scavenging free radicals. The inhibitory effect of the plant extract against bacterial pathogens may be due to the presence of phytochemicals. Thus, the results suggest that Kyllinga nemoralis is a potential source of antioxidants and could serve as the base for drug development. 相似文献