D. Muralidhara Rao

Bioavailability may be considered as one aspect of drug product quality that links the in-vivo performance of the drug product used in clinical trials with studies demonstrating evidence of safety and efficacy. In the present study, the bioavailability was performed for the qualitative evaluation of the L-lysine produced by modified Corynebacterium glutamicum. Thirty 3-week-old male Sprague-Dawley rats weighing 45-55 g were used. The animals were divided into three groups. The first group was kept on a protein free basal diet which was supplemented with the biotechnologically modified L-lysine from Corynebacterium glutamicum. The second group comprised of animals which were fed the same basal diet but supplemented with a marketed preparation of L-lysine. The third group was kept on a regular protein diet which served as a control. The animals were fed ad libitum for 13 days, during which weight gain and food consumption were recorded and food conversion efficiency (FCE; weight gained/weight food eaten) was calculated. Ratios of means were calculated using the (least-square means)LSM for untransformed and ln-transformed FCE. The bioavailability was estimated by measuring the pharmacological activity (weight gained) and compared with that of the marketed preparations of L-lysine under similar conditions. For the study reference and test samples,-s the 95% confidence interval fell within the range of 97.72 and 103.61, which was the indication of bio similarity for biological activity of both the samples.