Implementation of good manufacturing practices (GMP) to improve the quality of smoked fish (Scombercolias).

For several years, fish smoking has been the widely adopted processing method among artisanal fish smokers located along the coastal zones in many parts of West Africa including Ghana. However, several issues pertaining to biochemical and microbiological contaminants still remain, mainly because of the suboptimal, unhygienic fish handling during the processing. To help curtail the problem, we developed and implemented a simple good manufacturing practice (GMP) system for experimentation at two local fish smoking facilities (Facility A, FA; Facility B, FB) to assess the effectiveness for improving the quality of smoked fish. The implementation of GMP did not affect the physical properties of the smoked fish but improved the peroxide value, total volatile base nitrogen, polyaromantic hydrocarbons and histamine levels. The total aerobic counts decreased from 3.96 ± 0.12 cfu/g to 1.52 ± 0.28 cfu/g (FA) or from 4.10 ± 0.2 cfu/g to 1.85 ± 0.85 cfu/g, (FB). The coliforms and Escherichia coli decreased respectively from 1.69 ± 0.12 cfu/g and 1.15 ± 0.21 cfu/g (FA) and from 1.74 ± 0.37 cfu/g and 1.24 ± 0.37 cfu/g, (FB) to below detection (no observed colony) after introducing the single use of potable water, use of smoking oven and fish core temperature of 108.1 ± 7.5 °C and 82.5 ± 3.9 °C, respectively for 2 h, wearing of safety apparels, drying and cooling of smoked fish under nets, and the use of waste disposal bins. The results show that sensitization and training of fish smokers in GMP may be relevant for improving the microbial and overall quality of smoked fish.

Identification of molecular determinants of antibiotic resistance in some fish farms of Ghana.

Antimicrobial resistance is a global health challenge caused by the ability of microorganisms including bacteria, fungi, protozoans and viruses to survive the effects of drugs that hitherto were effective against them. This study sought to investigate the presence of antibiotic-resistant bacteria and their corresponding molecular determinants in fish farms of the Central and Western Regions of Ghana. Management practices and antibiotic use at the fish farms were obtained through the administration of a questionnaire. Coliform and Gram-positive bacterial loads of catfish (Clarias gariepinus), tilapia (Oreochromis niloticus) intestinal microbiota, and pond water samples recovered on MacConkey Agar and Mannitol Salt Agar were determined. Bacterial isolates were identified using various biochemical assays. Antibiotic resistance profiles and possible responsible genes of bacterial isolates were determined using the disc diffusion and Polymerase Chain Reaction (PCR) methods respectively. The study revealed that none of the fish farm managers admitted using antibiotics for prevention and treatment of diseases and no major disease outbreak had ever been recorded. Bacterial loads of pond water exceeded the acceptable level of ≤100 E. coli and <10 coliforms per mL for wastewater recommended for use in fish farming. In all, 145 bacterial isolates comprising 99 Gram negative and 46 Gram-positive bacteria were stored and identified. Most isolates were resistant to at least an antibiotic. Both Gram-negative and Gram-positive bacteria were highly resistant to beta-lactam antibiotics with a corresponding high percentage detection of the bla TEM gene compared to other classes of antibiotics. This study has revealed the presence of various molecular determinants of antibiotic resistance including bla TEM, cmIA, qnrS, tetB and bla CTX-M, in multidrug-resistant bacteria at some fish farms in Ghana. There is the need to increase awareness about risks associated with the misuse and overuse of antibiotics by humans and the potential risk of spread of multi-drug resistant-bacteria in the environment.

Molecular Structure-Based Screening of the Constituents of Calotropis procera Identifies Potential Inhibitors of Diabetes Mellitus Target Alpha Glucosidase.

Diabetes mellitus is a disorder characterized by higher levels of blood glucose due to impaired insulin mechanisms. Alpha glucosidase is a critical drug target implicated in the mechanisms of diabetes mellitus and its inhibition controls hyperglycemia. Since the existing standard synthetic drugs have therapeutic limitations, it is imperative to identify new potent inhibitors of natural product origin which may slow carbohydrate digestion and absorption via alpha glucosidase. Since plant extracts from Calotropis procera have been extensively used in the treatment of diabetes mellitus, the present study used molecular docking and dynamics simulation techniques to screen its constituents against the receptor alpha glucosidase. Taraxasterol, syriogenin, isorhamnetin-3-O-robinobioside and calotoxin were identified as potential novel lead compounds with plausible binding energies of -40.2, -35.1, -34.3 and -34.3 kJ/mol against alpha glucosidase, respectively. The residues Trp481, Asp518, Leu677, Leu678 and Leu680 were identified as critical for binding and the compounds were predicted as alpha glucosidase inhibitors. Structurally similar compounds with Tanimoto coefficients greater than 0.7 were reported experimentally to be inhibitors of alpha glucosidase or antidiabetic. The structures of the molecules may serve as templates for the design of novel inhibitors and warrant in vitro assaying to corroborate their antidiabetic potential.