Investigation of the Antimicrobial Activity and <i>in Vivo </i>Cytotoxicity of <i>Diospyros malabarica </i>(Desr.) Kostel. Fruit Extracts

Mankind is facing an unprecedented threat of existence due to the antibiotic resistance developed by bacteria. The unripe fruits of Diospyros malabarica (Desr.) Kostel. (family: Ebenaceae) can be considered as one of the natural sources to tackle this issue. The present study is designed to assess the antimicrobial activity of D. malabarica seed and flesh ex-tracts. Herein, D. malabarica extracts were prepared using polar solvents (i.e., water and 70% ethanol) and their antimicrobial activity as well as in vivo toxicity was investigated. Their antibacterial activity was investigated against gram positive (Bacillus subtilis) and gram negative (Escherichia coli DH5α, and Salmonella typhi) bacteria at different time points. All the extracts showed the highest antibacterial activity after 2 hours of incubation. The aqueous seed extract showed the maximum zone of inhibition (i.e., ~13 mm) against Bacillus subtilis with a minimum inhibitory concentration (MIC) value of 2 μg/μl. The an-tibacterial propensity was also confirmed through trypan blue dye exclusion assay, CellToxTM Green assay, and lipid peroxidation (LPO) assay. On the other hand, the etha-nolic seed extract demonstrated higher antifungal activity through inhibition of mycelial growth. All the extracts showed excellent hemocompatibility against both human and rat red blood cells (RBCs). They also did not show any toxicity to rat liver and kidneys. Taken together, this study demonstrates that the aqueous and ethanolic extracts of D. malabarica seed and flesh could be an effective source of natural antimicrobial agents with no cytotox-ic activity.

Enhanced Chimp Optimization Algorithm Using Attack Defense Strategy and Golden Update Mechanism for Robust COVID-19 Medical Image Segmentation

Medical image segmentation is a powerful and evolving technology in medical diagnosis.In fact,it has been identified as a very effective tool to support and accompany doctors in their fight against the spread of the coronavirus(COVID-19).Various techniques have been utilized for COVID-19 image segmentation,including Multilevel Thresholding(MLT)-based meta-heuristics,which are considered crucial in addressing this issue.However,despite their importance,meta-heuristics have significant limitations.Specifically,the imbalance between exploration and exploitation,as well as premature convergence,can cause the optimization process to become stuck in local optima,resulting in unsatisfactory segmentation results.In this paper,an enhanced War Strategy Chimp Optimization Algorithm(WSChOA)is proposed to address MLT problems.Two strategies are incorporated into the traditional Chimp Optimization Algorithm.Golden update mechanism that provides diversity in the population.Additionally,the attack and defense strategies are incorporated to improve the search space leading to avoiding local optima.The experimental results were conducted by comparing WSChoA with recent and well-known algorithms using various evaluation metrics such as Feature Similarity Index(FSIM),Structural Similarity Index(SSIM),Peak signal-to-Noise Ratio(PSNR),Standard deviation(STD),Freidman Test(FT),and Wilcoxon Sign Rank Test(WSRT).The results obtained by WSChoA surpassed those of other optimization techniques in terms of robustness and accuracy,indicating that it is a powerful tool for image segmentation.