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Fusarium oxysporum is one of the most harmful soil-borne pathogens that cause root rot, damping-off, and wilt disease in many plant species. Management of Fusarium oxysporum diseases is often by using many harmful and expensive chemical fungicides which have many harmful effects on the environment and human health. The current study was conducted to identify the chemical constituents of black cumin seeds' methanolic extract and investigate the ability of the major constituents to inhibit the Fusarium oxysporum trypsin-like serine protease, which play an important role in F. oxysporun pathogenicity. The HPLC-MS analysis of black cumin seeds' methanolic extract revealed the presence of seven major compounds: amentoflavone, Procyanidin C2, Quercetin3-O-sophoroside-7-O-rhamnoside, 5,7-Dihydroxy-3,4-dimethoxyflavone, Borapetoside A, tetrahydroxy-urs-12-en-28-O-[b-D-glucopyranosyl (1-2)-b-D-glucopyranosyl] ester, and kudzusapongenol A-hexA-pen. The results of molecular docking between these compounds and the active site of Fusarium oxysporium trypsin showed that only four compounds were able to bind to the active site of F. oxysporum trypsin. Amentoflavone, 5,7-Dihydroxy-3,4-dimethoxyflavone, and Quercetin3-O-sophoroside-7-O-rhamnoside have the highest binding energy, −6.4, −6.5, and −6.5 Kcal/mol, respectively. In addition, the results clarify that 5,7-Dihydroxy-3,4-dimethoxyflavone was the only compound to form a hydrogen bond with Asp189 (the residue responsible for substrate specificity). The results of the study strongly indicate that flavonoids of black cumin seeds' methanolic extract could be used as effective inhibitors for the F. oxysporum trypsin-like serine protease. [ABSTRACT FROM AUTHOR]

Liver toxicity is a common condition that can be induced by environmental pollutants. The present study explored the hepatoprotective activity of steroidal saponins extracted from the yam plant versus CC14-induced hepatotoxicity in albino rats. Twenty-five albino rats were classified into 5 groups. Rats of group (G1) were provided a basal diets and drinking water and served as un-treated controls. Other groups were administered CC14 orally twice a week at a dose of 400 mg/kg. The second group (G2) did not receive any further treatment and served as a positive controls while rats in the groups G3, G4 and G5 were administered saponins (50,100 and 200 mg/kg body weight, respectively) for six weeks in the remaining groups. The hepatoprotective activity of saponins was assessed by measurement of liver enzymes, kidney function tests, malondialdehyde content, and antioxidant defense enzymes activities in serum of these rats. Saponins administration improved liver and renal function and significantly increased the activities of catalase, glutathione peroxidase (GSH-PX), glutathione reductase GSH-RD and superoxide dismutase SOD. These increases were linked to a considerable decrease in serum malondialdehyde levels, indicating that lipid peroxidation was being mitigated. Thus, the concentration of saponins (200 mg/kg) is the best concentration of protection against CC14-induced hepatic injury, improved liver and renal function, and reduced oxidative stress in rats. [ABSTRACT FROM AUTHOR]

The present study evaluated the ability of different extracts of cinnamon and black cumin seeds to inhibit the growth of the phytopathogenic fungus Rhizoctonia solani and its extracellular cell wall degrading enzymes. Concentrations of 300 and 450 ppm of methylene chloride and hexane extracts of cinnamon completely inhibited the growth of R. solani after 72 hours of incubation at 25±1°C in vitro. Methylene chloride or hexane extracts of black cumin seeds at 4000 ppm after 72 hours inhibited the growth of R. solani by 37 and 39% respectively. Moreover, black cumin seed hexane extract at 2000 ppm inhibited 55% and 38% of the activity of pectin lyase (PL) and polygalacturonase (PG) respectively. In addition, the methanolic extract of black cumin seeds at 2000 ppm exhibited a significant reduction of exo-protease activity (74.8%). GC-MS analysis results showed that linoleic acid is the main component of the fixed oil fraction of black cumin seed hexane extract while (E)-cinnamaldehyde is the main component in both hexane and methylene chloride extracts of cinnamon. HPLC-MS analysis of black cumin seeds methanolic extract showed that amentoflavone, was the main component. Docking was used to identify the major component interaction with pectin lyase A and exo-protease. [ABSTRACT FROM AUTHOR]

Nanotechnology takes a significant position to control pests. Silicon dioxide nanoparticles (SiO2-NPs) is considered one of the best alternates to chemical pesticides for plant crop protection from harmful arthropods such as phytophagous mites, Tetranychus urticae. Therefore, this study aims to evaluate the effect of (SiO2-NPs) to control T. urticae. Under greenhouse conditions, the results revealed, in larval stage, high mortality percentage (99.05±0.83%) followed by eggs (98.74±1.22%). Also, nymph stage recorded high mortality (94.66±1.81%) at high concentration 1500 ppm. While the adult females of T. urticae recorded mortality 91.92±1.02% after 72h. Eventually, the immature stages of T. urticae were susceptible to (SiO2-NPs). Meanwhile, at laboratory evaluation on immature stages of T. urticae which resulted from live treated females during 96h showed a sharp decrease in average numbers of eggs through 96h, at 1000 and 1500 ppm. No numbers of the larval stage were recorded at 1500 ppm. No numbers of nymph stage were recorded at all concentrations and periods. Moreover, activity of AChE was significantly inhibited at 1500 ppm, while activity of glutathione-Stransferase was significantly increased after 72 h. Finally, (SiO2-NPs) are effective against immature stages of T. urticae under greenhouse and laboratory conditions. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the effect of solar UV radiation on defensive enzymes activities in lettuce seedlings. Seeds of lettuce were grown in high tunnels for 35 days, exposed to three different levels of solar UV, created by using three different types of plastic films. Each plastic film transmits different levels of solar UV (0% in UV-B, 4% in UVL and 83% in UV-T). The obtained results indicated that solar UV radiation has led to significant decrease in seedling fresh weight. UV-B treatment resulted the highest shoot and root length while UV-T treatments exhibited the highest shoot: root ratio. Solar UV radiations have no effect on peroxidase activity in shoots. While ascorbate peroxidase was activated and catalase was inhibited in shoot by UV-T treatments. In lettuce roots, peroxidase, ascorbate peroxidase, and catalase activities were increased by increasing the level of solar UV radiation. In case of UV-T, phenylalanine ammonia lyase (PAL) activity in both shoots and roots of lettuce seedlings was higher than those of other treatments. In addition, Phenols are accumulated in lettuce shoots as a result of UV radiation in UV-L and UV-T treatments. Also, phenols in roots increased by increasing solar UV dose. The study concluded that solar UV radiation induced some antioxidant enzymes, increased the accumulation and biosynthesis of phenolic compounds and reduced lettuce seedlings growth [ABSTRACT FROM AUTHOR]

Drought is one of the most harmful abiotic stresses in arid and semiarid regions, so, field experiments were performed to examine biochar impact (15 or 20 t ha-1) on soil properties, physiological, morphological, and yield of barley under drought conditions. Our results displayed that drought caused a remarkable decrease in stem height and leaf area. Additionally, relative water contents (RWC%), chlorophyll a and b concentrations, as well as yield parameters were significantly reduced under drought. Conversely, lipid peroxidation (MDA), electrolyte leakage (EL%), and enzymatic activity were significantly augmented in the stressed plants during both seasons. Application of biochar led to improve leaves number (15.3), stem height (57%) and leaf area. Also, physiological characters like chlorophyll (72%) and RWC (33%), as well as yield, were increased considerably. Contrariwise, MDA and EL were reduced significantly (47 and 54%) under biochar application; furthermore, biochar led to regulate peroxidase and catalase activity in the stressed plants. It is concluded that biochar treatment can significantly improve soil properties, particularly soil EC (dSm4), soil organic matter % and soil pH as well as increase yield characters via improving stress tolerance of barley under drought conditions; the best treatment was 20 t biochar ha-1 in the plants irrigated twice. [ABSTRACT FROM AUTHOR]