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Bila, S.

Publications and source records attributed to Bila, S..

2 recordsLinked to original sources

Assessing Mozambican Honey Quality: Differential Physical, Chemical and Microbiological Characteristics in Formal and Informal Markets

Honey is a natural product made by bees and is widely valued as a healthy food. Its quality can deteriorate due to microbial activity and physical or chemical changes. This study assessed honey from formal (n=12) and informal (n=12) markets in three Mozambican provinces: Maputo, Sofala, and Inhambane, to evaluate its quality and safety. Physicochemical parameters such as viscosity, water activity (Aw), pH, ash content, total soluble solids, and diastase activity were measured using standard AOAC methods. Microbiological quality was evaluated by counting aerobic mesophilic bacteria, moulds and yeasts, and by checking for pathogenic bacteria, including Escherichia coli and Salmonella species. The results showed marked differences. Honey from informal markets had a significantly higher ash content (0.613% {+/-} 0.079%), which is a recognized indicator of contamination (p < 0.05). In contrast, formal market samples demonstrated superior quality with greater total soluble solids (77.84 {degrees}Brix {+/-} 0.75{degrees}Brix) and viscosity (2.168 {+/-} 0.755 Pa.s). All honey samples from formal markets retained diastase activity, while 25% (3 out of 12) of informal market samples showed no enzymatic activity. From a microbiological perspective, all samples were within safe limits. In conclusion, the physicochemical irregularities observed in honey from informal markets underline the urgent need for better hygiene practices and stronger regulatory enforcement to protect consumers and strengthen the local honey industry.

biochemistry↗

In situ protein crystallography: a single-crystal electron diffraction pipeline for structure determination inside living cells.

Intracellular crystallization is an emerging approach in structural biology that bypasses the need for protein purification. An InCellCryst pipeline was recently established for structure determination by serial X-ray crystallography. Serial crystallography requires the exposure of tens of thousands of cells containing intracellular crystals, precluding high-resolution structural studies on proteins with low numbers of crystals. To overcome this limitation, we combined the InCellCryst approach with the advantages of 3D electron diffraction and established the new IncellED method. Using microcrystals of the HEX-1 protein from Magnaporthe grisea, grown inside High Five insect cells, we demonstrate that electron diffraction data collected from a single crystal yields a high-resolution structure at 1.9 [A] resolution, comparable to 1.8 [A] achieved by serial X-ray crystallography. The IncellED methodology opens structure determination for proteins that crystallize with low efficiency and use widely available electron cryo-microscope infrastructure, paving the way for intracellular macromolecular electron crystallography at high resolution.

biophysics↗