ALOE IRAFENSIS AN ENDEMIC PLANT OF YEMEN: PHYTOCHEMICAL SCREENING, ANTIBACTERIAL, ANTIOXIDANT, AND WOUND-HEALING ACTIVITIES

Objectives: The objectives of the study were to determine the phytochemical constituents and assess the antibacterial, antioxidant, and wound-healing properties of the methanol extracts of Aloe irafensis. Methods: Methanol extracts of A. irafensis’s latex, gel, and green skin were screened for their phytochemical constituents. All three extracts were investigated regarding their antibacterial potential using disc diffusion and microdilution assays, and their antioxidant activity using 2,2-diphenyl-1- picrylhydrazyl free-radical scavenging assay. Histopathological study of wound healing area was performed for the latex extract in male albino rats. Results: The methanol extracts of A. irafensis revealed the presence of carbohydrates, steroids, phenols, tannins, and anthrones. The latex extract showed greater inhibition zones against Staphylococcus aureus and Pseudomonas aeruginosa (24 and 17 mm, respectively) and minimum inhibitory concentration values of 1.25 and 2.50 mg/ml, respectively. The latex extract showed the highest antioxidant activity (IC50 of 65.54 μg/ml), followed by green skin (IC50 of 89.48 μg/ml). The latex extract significantly accelerated the rate of wound healing in rats (p<0.01), compared to fucidin ointment, a reference control. Histological findings showed remarkably less scar width at wound closure site in the latex extract-treated wounds. Granulation tissue contained fewer inflammatory cells and more fibroblasts in wounds treated with the latex extract compared to those treated with the vehicle. Conclusion: A. irafensis latex extract is a potential source of bioactive compounds that can be used as antioxidant, antibacterial, and wound healing agents

New Thiazolidine-4-One Derivatives as SARS-CoV-2 Main Protease Inhibitors

It has been more than four years since the first report of SARS-CoV-2, and humankind has experienced a pandemic with an unprecedented impact. Moreover, the new variants have made the situation even worse. Among viral enzymes, the SARS-CoV-2 main protease (Mpro) has been deemed a promising drug target vs. COVID-19. Indeed, Mpro is a pivotal enzyme for viral replication, and it is highly conserved within coronaviruses. It showed a high extent of conservation of the protease residues essential to the enzymatic activity, emphasizing its potential as a drug target to develop wide-spectrum antiviral agents effective not only vs. SARS-CoV-2 variants but also against other coronaviruses. Even though the FDA-approved drug nirmatrelvir, a Mpro inhibitor, has boosted the antiviral therapy for the treatment of COVID-19, the drug shows several drawbacks that hinder its clinical application. Herein, we report the synthesis of new thiazolidine-4-one derivatives endowed with inhibitory potencies in the micromolar range against SARS-CoV-2 Mpro. In silico studies shed light on the key structural requirements responsible for binding to highly conserved enzymatic residues, showing that the thiazolidinone core acts as a mimetic of the Gln amino acid of the natural substrate and the central role of the nitro-substituted aromatic portion in establishing π-π stacking interactions with the catalytic His-41 residue

Screening of Salt-stress, Antioxidant Enzyme, and Antimicrobial Activity of Leave extracts of Mangroves Avicennia marina L. from Hodaidah, Yemen

In the present study the salinity stress, antioxidant enzyme and antimicrobial activities of leaf extract of Avicennia marinawere investigated. As visualized from SDS-PAGE, no differences was found in number of protein band, but the intensities of several protein bands having apparent molecular mass by reduced severely in salt treated samples with enhanced activities of CAT, POX and GPX. Escherichia coli (ATCC8739), Staphylococus aureus (ATCC 6538), and Bacillus subtilis (ATCC6633) and fungus (Candida albicans ATCC 2091, and Aspergillus niger ATCC 16404) were used as the test pathogenic bacteria and fungi, respectively in this study. The Avicennia marina extract possessed antibacterial activity against E. coli, S. aureus, and B. subtilis (12, 6, and 7 mm respectively), with antifungal activity against C. albicans and A. niger (9 and 10 mm)

Screening of Salt-stress, Antioxidant Enzyme, and Antimicrobial Activity of Leave extracts of Mangroves Avicennia marina L. from Hodaidah, Yemen

In the present study the salinity stress, antioxidant enzyme and antimicrobial activities of leaf extract of Avicennia marinawere investigated. As visualized from SDS-PAGE, no differences was found in number of protein band, but the intensities of several protein bands having apparent molecular mass by reduced severely in salt treated samples with enhanced activities of CAT, POX and GPX. Escherichia coli (ATCC8739), Staphylococus aureus (ATCC 6538), and Bacillus subtilis (ATCC6633) and fungus (Candida albicans ATCC 2091, and Aspergillus niger ATCC 16404) were used as the test pathogenic bacteria and fungi, respectively in this study. The Avicennia marina extract possessed antibacterial activity against E. coli, S. aureus, and B. subtilis (12, 6, and 7 mm respectively), with antifungal activity against C. albicans and A. niger (9 and 10 mm)

Impact of country-level corporate governance on entrepreneurial conditions

The present study examines the effect of country-level corporate governance (CLCG) and Directors' Liability (DL) on Entrepreneurial Framework Conditions (EFCs) across 52 countries from 2014 up to 2017 using balanced panel data and Panel Correction Standard Error estimation. The results revealed that the CLCG has a significant impact across EFCs dimensions. Further, the results declared that the impact of DL is significant and positive in countries that have a high score of DL, but this impact is statistically negative in countries that have a low score of DL. The findings have momentous implications for entrepreneurs, policymakers, regulators, international organizations, and academicians. The study makes novel contributions to the strand literature underpinning country-level governance and the role of directors' liability with EFCs. It brings a useful insight into a previously undocumented area of research highlighting the importance of CLCG dimensions and DL as important factors and determinants for better entrepreneurial conditions

Alternative forage feeds for beef cattle in Northwestern Alberta, Canada: forage yield and nutritive value of forage brassicas and forbs

Forbs and forage brassicas are non-traditional forage crops in northwestern Alberta, Canada. Ten forage brassicas (barkant turnips, bayou kale hybrid, daikon radish, collard, inka brand marrowstem kale, malwira turnip rape, purple top turnips, tillage radish, vivant hybrid cross and winfred) and four forbs (buckwheat, chicory, plantain and phacelia) were seeded on 25 May 2018 and 23 May 2019. The above-ground parts of plants were harvested for forage yield and nutritive quality on 15 August 2018 and 29 August 2019. Forage dry matter (DM) yield, crude protein (CP) and total digestible nutrients (TDN) respectively varied from 2953 to 10740 kg DM ha−1, 12.2–23.5% CP and 58.8–77.9% TDN. Some crops had no nitrate (ant-nutritional factor) detected, while six crops (bayou kale cross, chicory, phacelia, plantain, purple top turnips and tillage radish) had nitrate concentrations ranging 0.26–0.56%, considered toxic for beef cattle. In general, the brassicas and forbs investigated produced forage with high nutritional quality. Based on forage DM yield and nitrate level in the forage, the crops with the most attractive forage options that can provide alternative forage feed for beef cattle production from this study would be buckwheat, daikon radish, inka brand marrowstem kale and forage collards