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Background: Endophytes are the richest sources of natural compounds, showing biological varieties and pharmacological activities. Objective: This study aims to isolate bioactive secondary metabolites from endophytic Aspergillus tubenginses with study the biological activity of the isolated bioactive compounds. Materials and Methods: Anofinic acid were obtained from Aspergillus tubenginses crude extract using chromatographic techniques and characterized by spectral analysis. Results: Nine endophytic fungi were isolated from Hyoscyamus muticus plant. The most efficient isolate was AF3 identified as Aspergillus tubenginses ASH4 by 18S rRNA gene sequencing. Anofinic acid is an isolated active metabolite biosynthesized by A. tubenginsis was extracted from ethyl acetate with UPAC name of 2,2-dimethyl-2H-1-benzopyran-6-carboxylic acid. It shows a strong antimicrobial activity against human pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Candida albicans and Bacillus subtilis. Moreover, anofinic acid inhibits biofilm formation and has antioxidant activity, with strong activity against some carcinoma cells such as HCT-116, Hep-G2 and MCF-7. Conclusion: Anofinic acid was purified from the endophytic Aspergillus tubenginses crude extract and showed antimicrobial, antibiofilm, antioxidant, anticancer activities. [ABSTRACT FROM AUTHOR]

Amidases (L-asparaginase and L-glutaminase) catalyze the deamination process of L-asparagine and L-glutamine to their corresponding acidic form with ammonia releasing. Both enzymes are considered one of the most biomedical and biotechnologically important groups of enzymes, besides their international contributing as an important commercial products. L-asparaginase and L-glutaminase have been receiving more attention as antileukemic agent for treatment of acute lymphoblastic leukemia (ALL) and other types of cancer. On the other hand, these enzymes also used in food manufacture for their hydrolysis effect and is a possible way to decrease the amount of free L-asparagine in the preliminary ingredients of food making, thus minimize the imminent risk of causing neurotoxic and carcinogenic acrylamide compound which formed when food heated above 120 °C. Glutamic and aspartic acid are important amino acids in food processing achieve a delicious, fine, sour and umami taste beside their nutritional important to food. A recent review discusses the mode of action of L-asparaginase and L-glutaminase. Also, this review lists the sources of L-asparaginase and L-glutaminase, production optimization of enzymes, and uses of the two enzymes in cancer therapy and other industrial purposes. [ABSTRACT FROM AUTHOR]

PHYSIOLOGICAL and biochemical characteristics of Fusarium oxysporum and Trichoderma viride isolated from old manuscripts of the General Book Organization of Egypt including effects of incubation periods, carbon sources, temperature, pH and relative humidity on linear growth (mm) and dry weight (mg) were established. Cellulolytic activity (Avicelase, CMCase, and Fpase were measured by the size of the clear zone on specific media. The results show that the best incubation period for F. oxysporum was 9 day on PDA solid medium and 12 day for liquid medium, while for T. viride was 6 and 9 day for solid and liquid media respectively. Cellulase production increased gradually over an, incubation period up to a maximum of 18 day for both F. oxysporum and T. viride beyond which a slight decline in the enzyme activity could be observed. The two isolates grow and attain maximum linear and dry weight at temperatures degree between 25 and 30°C. Both organisms can grow on PDA solid medium along a pH ranging from pH 3.5-8.5, with maximum growth at pH 3.5-6.5. F. oxysporum and T. viride grow effectively on all tested carbon sources (sucrose, maltose, lactose, glucose, arabinose, starch, pectin and raffinose) reaching maximum growth after 7 days of incubation. Cotton pulp was considered the best carbon source for inducing the highest Avicelase enzyme activity for both F. oxysporum and T. viride. Also, maximum growth was attained over a range of relative humidity, as the growth of F. oxysporum was increased by increasing the RH up to 92.3% and up to 100% for T. viride. [ABSTRACT FROM AUTHOR]

The agar diffusion method was used to determine the antimicrobial activities of Euphorbia hirta (EH) and Polygonum plebeium (PP) against S.aureus, B39. Ethyl acetate extract of Euphorbia hirta (EH) and Polygonum plebejum (PP),was the most effective solvent. MIC of plant extract Polygonum plebeium (PP) and Euphorbia hirta (EH) was 25mg/ ml. The antimicrobial activity of ethyl acetate extract of E. hirta (EH) and P. plebeium (PP) was more effective when incubated at 25°C for 10 min with MRSA, B39; pH 5 was more effective against MRSA, B39. Light condition for 24hr was effective against MRSA, B39; Static condition had slight effectiveness against MRSA, B39. Xylose exhibited the highest activity on MRSA, B39; no amino acids, metallic ions and vitamins were effective. Ethyl acetate extract of E. hirta (EH) was subjected to column chromatography and monitored with TLC, 5 spots were detected. Anti MRSA spots were identified as Hydroquinone and O-coumaric acid. [ABSTRACT FROM AUTHOR]

Thirteen microbial isolates were evaluated for green synthesis of Mg and Mn nanoparticles. The isolates were come from soil and wastewater samples from detergent processing industry. Metallotolerance ability of isolates was assessed towards these metals. Bacterial isolate B4 Mg/W was selected as highly extremo-tolerant for Mg+2 and can grow between 800 to 15000ppm (80-1500%)and was identified as Pseudomonas stutzeri, B4 Mg/W. Fungal isolate F4 Mn/ S was selected as extremo-tolerant for Mn+2 and grow in the range 800 to 45000ppm (80-4500%) and was identified as Fusarium nygamai, F4 Mn/ S. Biosynthesis of the Mg and Mn nanoparticles was achieved in both cases extracellular and intracellular. The nanoparticles were characterized using atomic absorption spectrophotometer (AAS), dynamic light scattering (DLS) and transmission electron microscope (TEM). Pseudomonas stutzeri, B4 Mg/W nanoparticle size was ranges from (229.3-553.2 nm) with different mean number for each size, the maximum mean number 33.7% was that of the particles with size 356.2 r. nm and atomic absorption spectrophotometer (AAS) revealed uptake percentage of the metal was 35.17%. Fusarium nygamai, F4 Mn/ S nanoparticles ranges from (61.21-127.5 to 412.5 nm) with different mean numbers for each size, the maximum mean number 23.1% was that of the particle size 82.09 nm and range from 23.1 to 28.1 % and AAS was 27.07%. Antimicrobial activity against Streptococcus pyogenes RCMB010015, 31.25 and 62.5 mm followed by Candida albicans RCMB05035, 15.63 and 62.5; then Staphylococcus aureus RCMB010027 and Eschericia coli RCMB010056 gave7.81and 62.5mm for both; while for Aspergillus fumigates RCMB02564 gave the least amount of inhibition 1.95 and 15.63mm; moreover Pseudomonas aeruginosa RCMB010043 was very resistant for both Pseudomonas stutzeri, B4 Mg/W and Fusarium nygamai, F4 Mn/S inracellular nanoparticles, respectively. [ABSTRACT FROM AUTHOR]

Thirteen microbial isolates were evaluated for green synthesis of Mg and Mn nanoparticles. The isolates were come from soil and wastewater samples from detergent processing industry. Metallotolerance ability of isolates was assessed towards these metals. Bacterial isolate B4 Mg/W was selected as highly extremo-tolerant for Mg+2 and can grow between 800 to 15000ppm (80-1500%)and was identified as Pseudomonas stutzeri, B4 Mg/W. Fungal isolate F4 Mn/ S was selected as extremo-tolerant for Mn+2 and grow in the range 800 to 45000ppm (80-4500%) and was identified as Fusarium nygamai, F4 Mn/ S. Biosynthesis of the Mg and Mn nanoparticles was achieved in both cases extracellular and intracellular. The nanoparticles were characterized using atomic absorption spectrophotometer (AAS), dynamic light scattering (DLS) and transmission electron microscope (TEM). Pseudomonas stutzeri, B4 Mg/W nanoparticle size was ranges from (229.3-553.2 nm) with different mean number for each size, the maximum mean number 33.7% was that of the particles with size 356.2 r. nm and atomic absorption spectrophotometer (AAS) revealed uptake percentage of the metal was 35.17%. Fusarium nygamai, F4 Mn/ S nanoparticles ranges from (61.21-127.5 to 412.5 nm) with different mean numbers for each size, the maximum mean number 23.1% was that of the particle size 82.09 nm and range from 23.1 to 28.1 % and AAS was 27.07%. Antimicrobial activity against Streptococcus pyogenes RCMB010015, 31.25 and 62.5 mm followed by Candida albicans RCMB05035, 15.63 and 62.5; then Staphylococcus aureus RCMB010027 and Eschericia coli RCMB010056 gave7.81and 62.5mm for both; while for Aspergillus fumigates RCMB02564 gave the least amount of inhibition 1.95 and 15.63mm; moreover Pseudomonas aeruginosa RCMB010043 was very resistant for both Pseudomonas stutzeri, B4 Mg/W and Fusarium nygamai, F4 Mn/S inracellular nanoparticles, respectively. [ABSTRACT FROM AUTHOR]

Background: COVID-19 patients are vulnerable to develop secondary microbial infections that are frequently multidrugresistant (MDR) and increase the severity of the disease and mortality risk, which has created an urgent need for the use of natural products as antimicrobial agents. Objective: This study aimed to evaluate and compare the polyphenol content of some honeybee products from different origins as well as their antimicrobial activity against some MDR secondary microbial infections in COVID-19 patients. Methods: During the winter of 2021, sixteen clinical microbial isolates were collected from sputum and chest swabs of COVID-19 patients from some hospitals in Cairo, Egypt, and their antimicrobial susceptibility testing was performed. The total phenolic content (TPC) and total flavonoid content (TFC) of eight honeybee products from different origins were evaluated, and their antimicrobial activity was determined by recording the inhibition zone diameter (IZD) and minimum inhibitory concentration (MIC). Results: According to results, Turkish propolis, Egyptian royal jelly sample1, and Egyptian honey contained the highest polyphenol content and consequently showed significant antimicrobial activity compared to other bee products under study. Turkish propolis contained elevated polyphenol contents (TPC= 322.33 mg Gallic acid (GAE)/100 g and TFC= 88.974 mg Quercetin (QUE)/100 g) and expressed its antimicrobial activity with IZD ranging 15.33-28.33 mm and MIC value of 0.105-7.5 mg/ml. Also, Egyptian royal jelly1 and Egyptian honey contained high polyphenol contents (TPC= 134.737 mg GAE/100 g and TFC= 78.162 mg QUE/100 g) and (TPC= 98.571 mg GAE/100 g and TFC= 44.487 mg QUE/100 g), respectively, and showed antimicrobial activity with IZD of 0.00-21.66 mm and 0.00-22.00 mm, respectively, as well as MIC values of 1.150-4.69% and 6.25-37.50%, respectively. Indeed, all honey and royal jelly samples showed no activity against Candida spp., while propolis exhibited good action against it. Conclusion: Honeybee products are promising natural products that possess unique antimicrobial activities that help to fight MDR secondary microbial infections in COVID-19 patients, in which their antimicrobial activity is largely affected by polyphenol contents and geographical origins. [ABSTRACT FROM AUTHOR]