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As a result of physiological changes and senescence, susceptibility of loquat fruit to postharvest diseases increases during storage at room temperature. The present study investigated the effects of postharvest anti-oxidant treatments on the physiological changes and the incidence of decay during storage at room temperature. Fresh-picked loquat fruit were treated with four solutions, tap water (control), 5 mM salicylic acid (SA), 2000 ppm ascorbic acid (AsA) and 5 mM citric acid (CA). All fruit were dipped into the above solutions for 5 min, air dried and stored under room conditions (18±2°C and 55% RH). Respiration rate, total soluble solids (TSS), titratable acidity (TA), flesh firmness, weight loss and decay were evaluated at three-day intervals until decayed fruit reached more than 50%. The results showed that postharvest treatments with anti-oxidants (especially SA) slowed down the respiration rate and weight loss, and maintained higher levels of flesh firmness.

Aims: This paper describes the In vitro study of protein binding by sildenafil citrate (SC) in presence of bisoprololfumarate (BF) and metformin hydrochloride (MH). Study Design: Study was designed to assess In vitro of quenching of bovine serum albumin (BSA) by sildenafil citrate (SC) in presence of bisoprolol fumarate (BF) and metformin hydrochloride (MH) by fluorescence spectrophotometry. Place and Duration of Study: Drug Analysis and Research Laboratory, Centre for Advanced Research in Sciences, University of Dhaka, Dhaka-1000, Bangladesh between December 2013 and March 2014. Methodology: In the present work, the In vitro study of quenching of BSA by SC in presence of BF Original Research Article Rokonujjaman et al.; BJMMR, 5(3): 362-375, 2015; Article no.BJMMR.2015.040 363 and MH have been studied by fluorescence emission spectroscopy under different conditions. At first, the BSA solution (20 μM) was prepared in phosphate buffer (pH =7.4) in eight test tubes and different amounts of sildenafil citrate was added to each BSA solution to obtain the final concentrations as 0, 20, 40, 80, 120, 160,240 and 320 × 10 -6 molL -1 , respectively. Then the fluorescence emission spectra of BSA-SC system were recorded for eight test tubes at two excitation wavelengths of BSA (λExmax= 280 nm and λExmax=293 nm) at 298 K and 308 K. Similarly, the fluorescence emission spectra of BSA-(SC+BF), BSA-(SC+MH) and BSA-(SC+BF+MH) systems were recorded at 280 nm and293 nm at 298 K and 308 K. Quenching constants were determined using the Stern-Volmer equation to provide a measure of the strength of quenching of BSA by SC in presence of BF and MH in all the systems. Results: The quenching of BSA by SC was increased in presence of BF and MH but remained close in presence of both BF and MH. Quenching constants were larger for the BSA-(SC+BF) system and ranked in the order as BSA-(SC+BF)>BSA-(SC+MH)>BSA-(SC+BF+MH)≈ BSA-SC at 280 nm at two different temperatures, respectively. But quenching at the excitation wavelength of 293 nm was ranked in order as BSA-(SC+BF) >BSA-(SC+MH) >BSA-(SC+BF+MH)>BSA-SC at 298 K and 308 K, respectively. Conclusion: It was found that BSA quenched by SC in presence of BF and MH, which indicated that the effectiveness of SC might be predominately influenced by these drugs.