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Mimusops laurifolia is a native species restricted to the Red Sea mountains and Gulf of Aden. Its leaves contain saponins with wide range of biological activities. The presented research aimed to prepare saponins-rich extract from n -butanol fraction of M. laurifolia leaves and screen it for promising antimicrobial activities. Minimum inhibitory concentration (MIC) of the prepared saponins against Candida albicans , and their potential anti-pathogenic and antivirulence effects were determined. Different concentrations of the saponins-rich extract were investigated for their antimicrobial potential, particularly against C. albicans , using the agar well diffusion method. To assess the potential antivirulence and antipathogenic effects, we carried out molecular docking of the bioactive saponins against four key enzymes in C. albicans , which are involved in virulence and/or pathogenicity. Different concentrations of the investigated mixture showed notable antifungal activity against C. albicans with an MIC value of 6.4 μg ml−1. Docking analysis of the investigated saponins showed their affinity toward the docked enzymes, particularly saponin 1 with secreted aspartic proteinase 3 and saponin 6 with secreted aspartic proteinase 5. Thereafter, the stability of these two protein-ligand interactions was investigated using molecular dynamics (MD) simulation. The molecular interactions between saponins and the enzymes' active sites were analyzed and discussed. [ABSTRACT FROM AUTHOR]

Aims: Infectious bronchitis virus (IBV) is a highly contagious, acute viral respiratory disease that mostly affects chickens. The poultry sector has suffered enormous losses as a result of IBV. Currently, live attenuated vaccines are routinely used to prevent and control IBV. However, due to the enormous genetic variety, vaccinations are becoming ineffective, with low cross-protection effects among vaccine serotypes. The present study aimed at investigating the possible antiviral effects of curcumin, epigallocatechin gallate (EGCG) and their mixtures against IBV in vivo. Methodology and results: Curcumin, EGCG and their combinations were administered to infected and uninfected chicken groups and viral load titers were determined by real-time PCR. The clinical symptoms of both the negative and positive control groups were also compared. Finally, the trachea tissues of each group were examined histopathologically. According to our findings, the viral titer and the clinical signs dropped significantly during the pretreatment infection procedure. Curcumin, EGCG and their combinations also show significant antiviral activities. Conclusion, significance and impact of study: This study clearly shown that natural compounds and their combinations, such as curcumin or/and ECGC can reduce viral pathogenicity in vivo, suggesting that they might have therapeutic implications in the poultry sector. [ABSTRACT FROM AUTHOR]

Background: Lutein and its isomerzeaxanthin are safe natural compounds. They are able to reduce the development of tumor and other chronic diseases. The objectives of the current study was to examine the cytotoxicity of lutein isolated and purified from alfalfa, safe and low-cost plant, on five different human cancer cell lines, namely (MCF-7), (HepG2), (A549), (PC3), and (HCT116), as well as normal (HFB4) cells. Method: We examined the cytotoxicity of lutein purified from Medicago sativa L and evaluate its activity against human liver HepG2, breast MCF-7, lung A549, prostate PC3, and colon HCT116 cancer cell lines using SRB assay in comparison with doxorubicin as a reference drug. Results: Results revealed that the tested extract could be a more promising anticancer agent in the case of MCF-7 (IC50, 3.10±0.47 µg/ml) compared with standard drug doxorubicin (IC50, 2.90±0.30 µg/ml). Moreover, the extract showed a moderate effect on HepG2 (IC50, 6.11±0.84 µg/ml) versus doxorubicin (IC50, 2.90±0.30 µg/ml); meanwhile, the extract showed no activity against A549, PC3, and HCT116 cells. The results further revealed that the extract had no toxicity against the growth of normal HFB4 cells versus doxorubicin. Conclusion: Lutein-rich extract from alfalfa had a major antiproliferative role in breast MCF-7 and liver HepG2 compared to doxorubicin. [ABSTRACT FROM AUTHOR]

The need of extremophile enzymes is increased. Such enzymes had found their utility in bio-industries such as leather, food, animal feed, textiles, and in bioconversions and bioremediation. Screening of microorganisms producing enzymes from different areas of soil led to the isolation of 38 isolates, the isolates were plate-screened for their ability to produce extracellular enzymes. The promising strains were selected and screened for their enzyme thermostability and screened quantitatively for potential industrial and therapeutic applications. Tolerance of selected microorganisms was investigated to a varied range of pH, salinity, and enzyme activity over a range of temperature. The genotypic identification of 16S rDNA sequence of the promising strains revealed that our strains were Streptomyces mutabilis, Streptomyces ghanaensis, Streptomyces rochei and Enterobacter cloacae. The isolated microorganisms quantified as an effective producer of industrially important enzymes amylase, cellulase, esterase, casienase and therapeutic enzyme L-asparaginase. All enzymes produced from the four isolates show enzyme activity and stability at different high temperature (60 °C, 80 °C, 100 °C). The amylase shows optimum activity at 37 °C, while the other four enzymes show optimum activity at different high temperature (60 °C, 80 °C). The study shows that Streptomyces mutabilis produce acidophilic enzyme amylase, Streptomyces ghanaensis produce acidophilic enzyme cellulase and neutrophilic enzyme esterase, Enterobacter cloacae and Streptomyces rochei produce alkalophilic enzymes (L-asparaginase, caseinase) respectively. Enzymes show highest enzyme activity at high NaCl concentration (5 and 7.5%). [ABSTRACT FROM AUTHOR]

Lipase catalytic activity is greatly influenced by immobilization on nanoparticles. In this study, lipase from Aspergillus niger was immobilized on TiO 2 nanoparticles with different morphologies: microspheres, nanotubes, and nanosheets. All TiO 2 samples were prepared by a hydrothermal method. Lipase/TiO 2 nanocomposites were prepared by a physical adsorption method through hydrophobic interactions. The prepared composites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). The catalytic activity of free and immobilized lipases was tested using sunflower oil in the presence of methanol to produce biodiesel at 40 °C for 90 min. The lipase immobilized on TiO 2 microspheres showed the highest activity compared to the lipase immobilized on TiO 2 nanotubes and nanosheets. To optimize the lipase-to-microsphere ratio, lipase was immobilized on TiO 2 microspheres in different microspheres/lipase, w/w, (S/L) ratios of 1:1, 1:0.75, 1:0.5, and 1:0.25. It was noticed that the hydrolytic activity follows the order 1:0.25 > 1:0.5 > 1:75 > 1:1. The immobilization yield activities were found to be 113, 123, 125, and 130% for the microspheres/lipase (S/L) ratios of 1:1, 1:0.75, 1:0.5, and 1:0.25, respectively., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)