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Diarylheptanoids from Alnus nepalensis leaves have been reported for promising activity against filariasis, a mosquito-borne disease, and this has prompted us to investigate its anti-malarial and safety profile using in-vitro and in-vivo bioassays. A. nepalensis leaf extracts were tested in-vitro against chloroquine-sensitive Plasmodium falciparum NF54 by measuring the parasite specific lactate dehydrogenase activity. Among all, the chloroform extract (ANC) has shown promising anti-plasmodial activity (IC50 8.06 ± 0.26 µg/mL). HPLC analysis of ANC showed the presence of diarylheptanoids. Efficacy and safety of ANC were further validated in in-vivo system using Plasmodium berghei-induced malaria model and acute oral toxicity in mice. Malaria was induced by intra-peritoneal injection of P. berghei infected red blood cells to the female Balb/c mice. ANC was administered orally at doses of 100 and 300 mg/kg/day following Peter's 4 day suppression test. Oral administration of ANC showed significant reduction of parasitaemia and increase in mean survival time. It also attributed to inhibition of the parasite induced pro-inflammatory cytokines as well as afford to significant increase in the blood glucose and haemoglobin level when compared with vehicle-treated infected mice. In-vivo safety evaluation study revealed that ANC is non-toxic at higher concentration. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Streptokinase is a well-established cost-effective therapeutic molecule for thrombo-embolic complications. In the current study, a tag-free variant of streptokinase with a native N-terminus (N-rSK) was developed using the Pichia expression system. A three-copy clone was screened that secreted 1062 mg/L of N-rSK in the complex medium at shake flask level. The biologically active (67,552.61 IU/mg) N-rSK recovered by anion exchange chromatography was predicted to contain 15.43% α-helices, 26.43% β-sheets. The fermentation run in a complex medium yielded a poor quality product due to excessive N-rSK degradation. Therefore, modified basal salt medium was also employed during fermentation operations to reduce the proteolytic processing of the recombinant product. The concomitant feeding of 1 g/L/h soya flour hydrolysate with methanol during the protein synthesis phase reduced the proteolysis and yielded 2.29 g/L of N-rSK. The fermentation medium was also supplemented with urea during growth and induction phases. The combined feeding approach of nitrogen-rich soya flour hydrolysate and urea during bioreactor operations showed significant improvement in protein stability and resulted in a 4-fold increase in N-rSK concentration to a level of 4.03 g/L over shake flask. Under optimized conditions, the volumetric productivity and specific product yield were 52.33 mg/L/h and 33.24 mg/g DCW, respectively. [ABSTRACT FROM AUTHOR]