The methylotrophic yeast Pichia pastoris is a well-established expression host, which is often used in the production of protein pharmaceuticals. This work aimed to evaluate the effect of various concentrations of ascorbic acid in mixed feeding strategy with sorbitol/methanol on productivity of recombinant human growth hormone (r-hGH). The relevant concentration of ascorbic acid (5, 10, or 20 mmol) and 50 g/L sorbitol were added in batch-wise mode to the medium at the beginning of induction phase. The rate of methanol addition was increased stepwise during the first 12 h of production and then kept constant. Total protein and r-hGH concentrations were analyzed and the results compared with sorbitol/methanol feeding using one-way analysis of variance. Moreover, an effective clarification process using activated carbon was developed to remove process contaminants like pigments and endotoxins. Finally, a three-step chromatographic process was applied to purify the product. According to the obtained results, addition of 10 mmol ascorbic acid to sorbitol/methanol co-feeding could significantly increase cell biomass (1.7 fold), total protein (1.14 fold), and r-hGH concentration (1.43 fold). One percent activated carbon could significantly decrease pigments and endotoxins without any significant changes in r-hGH assay. The result of the study concluded that ascorbic acid in combination with sorbitol could effectively enhance the productivity of r-hGH. This study also demonstrated that activated carbon clarification is a simple method for efficient removal of endotoxin and pigment in production of recombinant protein in the yeast expression system.

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Background: Over the past years, orally disintegrating films (ODFs) have been a suitable alternative to conventional oral dosage forms such as tablets and capsules, especially for patients with dysphagia. ODF is relatively a new dosage form which is prepared using hydrophilic polymers, which rapidly dissolve on tongue or buccal cavity and has other advantages of rapid onset of action and improved bioavailability. The aim of this study was formulation of ODF dosage forms containing alprazolam, which is a short-acting anxiolytic of the benzodiazepines class of psychoactive drugs. Materials and methods: Various polymers like hydroxy propyl methyl cellulose (HPMC6cps), sodium carboxy methyl cellulose (Na CMC), polyvinyl alcohol (PVA72000), and different plasticizers like propylene glycol (PG), polyethylene glycol (PEG400) with different percentage using solvent casting technique were used to prepare ODF formulations. Physicochemical tests including weight and thickness determination, disintegration time, assay and dissolution time were performed to find the optimum formulation. Results: The optimized formulation contained PVA72000 and PEG400 with disintegration time less than 60 seconds and acceptable dissolution rate. Conclusion: ODT dosage form of alprazolam with acceptable dissolution behavior and proper disintegration time was successfully formulated in this study.