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Background High losses of sorghum crops due to fungal diseases, such as grain mold and stalk rot, are economically harmful and cause increased use of environmentally damaging chemical fungicides, which also are detrimental to human health. Hence, finding safe and effective ways to manage fungal diseases of sorghum is urgently needed. Results In the present study, the antagonistic activities of Trichoderma viride and T. harzianum against different pathogenic fungal strains were evaluated in vitro using a dual culture assay. Furthermore, the anti-mycotic activity of Trichoderma spp. culture filtrates was evaluated against different fungal strains using a food poisoning technique. Additionally, the antifungal activities of ethyl acetate extracts of T. viride and T. harzianum against different pathogens were evaluated using a disk diffusion method. As indicated by the dual culture assay, T. harzianum suppressed 66.8, 69.5, 68.7, 54.6, 84.12, and 71.39% of the mycelial growth of Curvularia lunata, Exserohilum rostratum, Fusarium chlamydosporum, F. incarnatum, F. proliferatum, and Macrophomina phaseolina, respectively. T. viride was more effective for controlling the growth of these pathogens, inhibiting 81.0, 89.0, 63.0, 70.7, 84.4, and 71.8% of mycelial growth, respectively. Both E. rostratum and M. phaseolina showed resistance to carbendazim fungicide at all tested concentrations, whereas the fungicidal concentrations of carbendazim against C. lunata, F. chlamydosporum, and F. incarnatum strains were 2.50, 1.50, and 2.00 ppm, respectively. Furthermore, F. proliferatum was sensitive to carbendazim fungicide at all tested concentrations. Antifungal assays of the ethyl acetate extracts of T. viride and T. harzianum indicated the potent activity of these extracts against fungal phytopathogens with different susceptibility patterns. F. chlamydosporum was the most sensitive to the extracts of T. viride and T. harzianum with minimum inhibitory concentrations of 0.5 and 1.0 mg/disk, respectively. Conclusion The potent suppression of sorghum phytopathogens by T. viride and T. harzianum makes them potential sources of safe and effective natural fungicides compared to carbendazim fungicide.

Objectives Cancer is the most common cause of death every year. Moreover, high incidence of bacterial resistance to the most frequently used antibiotics contributes a significant death and disability worldwide. Hence, formulation of novel antimicrobial and anticarcinogenic agents is required. Methods In the current study, the antibacterial efficiency of clove extracts (acetonic, dichloromethane, ethanolic, and petroleum ether) against four pathogenic bacterial strains [Escherichia coli, Salmonella typhi, Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA)] was estimated by disc diffusion method. Furthermore, the anticancer potency of S. aromaticum extracts against HCT human colon carcinoma was appraised using MTT assay. The phytochemical ingredients of the most effective extract were determined using gas chromatography–mass spectrometry (GC–MS) analysis. Results and conclusion The dichloromethane extract presented the highest antibacterial potency against the pathogenic isolates recording minimum inhibitory concentration (MIC) of 1 mg/disc against MRSA strain and 0.5 mg/disc against both of E. coli and S. typhi strains. Furthermore, the minimum bactericidal concentration (MBC) of clove dichloromethane extract was recoded at 2 mg/disc against MRSA stain, and 1 mg/disc against E. coli and S. typhi strains. The dichloromethane extract of clove showed the lowest cytotoxic activity against HCT cell line whereas, the ethanolic extract exerted the highest efficacy with relative IC50 of 6.71 and 2.53 µg/ml respectively. GC–MS analysis revealed that the clove dichloromethane extract was comprised of eugenol (50.65%) and eugenyl acetate (12.54%) as major active components. In conclusion, clove extracts could be utilized as potential antibacterial and anticarcinogenic agents.

Background Saprolegniasis often cause a significant economic losses to fish hatchery and intensive fish industry. The treatment of saprolegnoid diseases with malachite green seems to have harmful effect and is considered as a mutagenic and carcinogenic substance. The teratogenic and carcinogenic potential of malachite green increased the necessity to find an effective alternative treatment to control the disease. Methods In the present study, seven fungicides used in agriculture were investigated to control Saprolegnia parasitica and S. diclina in vitro. The antifungal activity of each fungicide was compared with that of malachite green as reference fungicide using food poisoning technique. Fish toxicity of the effective fungicides was performed to detect the most applicable fungicides in fish aquarium. Results Four of seven fungicides were found to be effective against the two saprolegnoid fungi. Azoxystrobin and metalaxyl were the most effective fungicides inhibited fungal growth of the two saprolegnoid fungi completely at concentration of 200 ppm and 250 ppm respectively while cyazofamid and etridiazole were moderately effective. Acute toxicity assay of the two effective fungicides showed metalaxyl was low toxic to fish with LC50 of 360 ppm while azoxystrobin was 225 ppm. Hence, it was confirmed that 200 and 250 ppm of azoxystrobin and metalaxyl which completely inhibited mycelial growth of the saprolegniod fungi could be safely used for saprolegniasis control. Conclusion These fungicides which proved to be effective and fishery safer may be applicable as a aquatic fungicides avoiding teratogenic and carcinogenic risk of malachite green.

Alfalfa mosaic virus (AMV) is a worldwide distributed virus that has a very wide host range and causes significant crop losses of many economically important crops, including potato (Solanum tuberosum L.). In this study, the antiviral activity of Bacillus licheniformis strain POT1 against AMV on potato plants was evaluated. The dual foliar application of culture filtrate (CF), 24 h before and after AMV-inoculation, was the most effective treatment that showed 86.79% reduction of the viral accumulation level and improvement of different growth parameters. Moreover, HPLC analysis showed that a 20 polyphenolic compound was accumulated with a total amount of 7,218.86 and 1606.49 mg/kg in POT1-treated and non-treated plants, respectively. Additionally, the transcriptional analysis of thirteen genes controlling the phenylpropanoid, chlorogenic acid and flavonoid biosynthetic pathways revealed that most of the studied genes were induced after POT1 treatments. The stronger expression level of F3H, the key enzyme in flavonoid biosynthesis in plants, (588.133-fold) and AN2, anthocyanin 2 transcription factor, (97.005-fold) suggested that the accumulation flavonoid, especially anthocyanin, might play significant roles in plant defense against viral infection. Gas chromatography-mass spectrometry (GC-MS) analysis showed that pyrrolo[1,2-a]pyrazine-1,4-dione is the major compound in CF ethyl acetate extract, that is suggesting it acts as elicitor molecules for induction of systemic acquired resistance in potato plants. To our knowledge, this is the first study of biological control of AMV mediated by PGPR in potato plants.

Vulvovaginal candidiasis is a common health problem affecting about 75% of women at reproductive age. Teratogenicity and fetal toxicity resulting from antifungal therapy during pregnancy necessitates formulation of novel therapeutic agents. Disk diffusion method was performed to evaluate the antifungal activity of Mentha longifolia extracts against different candidal strains. Moreover, the anticancer activity of different M. longifolia extracts against MCF7 breast cancer cell line was evaluated by MTT assay. The M. longifolia n-hexane extract exhibited the highest antifungal activity, while the methanolic extract showed no antimicrobial activity against the tested Candida strains. Minimum inhibitory concentration (MIC) of n-hexane extract was 250 µg/disk against C. tropicalis while it was 500 µg/disk against C. albicans and C. glabrata. Minimum fungicidal concentration (MFC) was 0.5 mg/disk against C. albicans and C. tropicalis, and 1 mg/disk against C. glabrata. GC–MS analysis of the n-hexane extract was performed to detect the active phytochemical components. Menthone (18.37%) was the main phytochemical active component of n-hexane extract followed by butyloctanol (16.13%), 1,5-(1-Bromo-1-methylethyl)-2-methyl-2-cyclohexen-1-one (14.89%), α-tocopherol (13.13%), eugenol (12.21%), α-resorcylamide (11.56%), citronellal (3.71%), butylated hydroxytoluene (3.21%), isocaryophyllene (2.81%), 2-hexyldecanol (2.12%) and tau-cadinol (1.87%). The methanolic extract exhibited the highest anticancer activity against MCF7 breast cancer cell line while diethyl ether extract exhibited the lowest activity with IC50 of 91.67 and 244.70 µg/ml respectively. M. longifolia extracts could be used as a potential source of novel anticandidal and anti-carcinogenic therapeutic agents. Keywords: Vulvovaginal candidiasis, Mentha longifolia, Anti-candida, Minimum inhibitory concentration, Cytotoxicity, Phytochemicals

The widespread use of chemical control agents and pesticides for plant-pathogen control has caused many human health and environmental issues. Plant extracts and biocontrol agents have robust antimicrobial activity against different plant pathogens. However, their antiviral activities are still being investigated. In the present study, the methanol extract of Paronychia argentea was characterized and evaluated for its protective activity against the tobacco mosaic virus (TMV) infection in tomato plants under greenhouse conditions at 21 days post-inoculation. The results showed that the foliar application of P. argentea extract (10 µg/mL) enhanced tomato plant growth, resulting in significant increases in shoot and root parameters and total chlorophyll contents. Moreover, a significant reduction in TMV accumulation level in P. argentea-treated plants of 77.88% compared to non-treated plants was reported. Furthermore, induction of systemic resistance with significant elevation in production of antioxidant enzymes (PPO, CAT, and SOD) and transcriptional levels of the pathogenesis-related proteins (PR-1 and PR-7) and polyphenolic genes (CHS and HQT) were also observed. Out of 16 detected compounds, HPLC analysis revealed that the most abundant polyphenolic compounds found in P. argentea extract were gallic acid (5.36 µg/mL), kaempferol (7.39 µg/mL), quercetin (7.44 µg/mL), ellagic acid (7.89 µg/mL), myricetin (8.36 µg/mL), and ferulic acid (8.69 µg/mL). The findings suggest that the use of P. argentea extract as an effective and safe source for the production of bioactive compounds may offer a solution for a promising approach for the management of plant viral infections. To the best of our knowledge, this is the first report of the protective activity of P. argentea extract against plant viral diseases.

Background Candida vaginitis is a global health hazard that increases morbidity among women of childbearing age. Recent studies have revealed a high incidence of drug-resistant Candida strains. Additionally, treating Candida vulvovaginitis during pregnancy is challenging as antifungal therapy is associated with fetal abnormalities. Hence, it is important to develop novel therapeutic strategies to treat vulvovaginal candidiasis. Methods In this study, we used the disc diffusion method to evaluate the anticandidal activity of different Syzygium aromaticum extracts (methanol, ethyl acetate, n-hexane, and diethyl ether) against C. albicans, C. glabrata, and C. tropicalis. Furthermore, gas chromatography-mass spectrometry (GC-MS) analysis of different S. aromaticum extracts was performed to determine active components exhibiting anticandidal activity. Cytotoxicity of different clove extracts against the HUH7 cell line was evaluated. Results The ethyl acetate extract exhibited the highest antifungal activity against C. albicans, C. glabrata, and C. tropicalis with inhibition zone diameters of 20.9, 14.9, and 30.7 mm, respectively. The minimum inhibitory concentration of the S. aromaticum ethyl acetate extract was 250 μg/disc against C. tropicalis, and 500 μg/disc against C. albicans and C. glabrata, while the minimum fungicidal concentration was 0.5 mg/disc against C. tropicalis and 1 mg/disc against the C. albicans and C. glabrata. GC-MS analysis of the ethyl acetate extract revealed the main bioactive compound as eugenol (58.88%), followed by eugenyl acetate (23.86%), trans-caryophyllene (14.44%), and α-humulene (1.88%). The cytotoxicity assay indicated that the diethyl ether extract demonstrated the lowest toxicological effect against the HUH7 cell line, with a relative IC50 of 62.43 μg/ml; the methanolic extract demonstrated a higher toxicity (IC50, 24.17 μg/ml). Conclusion As the S. aromaticum extract exhibited high antifungal activity at low concentrations, it can be a potential source of natural antifungal drugs.

Due to environmental concern, the research to date has tended to focus on how textile dye removal can be carried out in a greener manner. Therefore, this study aims to evaluate the decolorization and biotransformation pathway of Mordant Orange-1 (MO-1) by Cylindrocephalum aurelium RY06 (C. aurelium RY06). Decolorization study was conducted in a batch experiment including the investigation of the effects of physio-chemical parameters. Enzymatic activity of C. aurelium RY06 during the decolorization was also investigated. Moreover, transformation and biodegradation of MO-1 by C. aurelium RY06 were observed using the gas chromatography-mass spectrometry. Manganese peroxidase, lignin peroxidase, laccase, 1,2-dioxygenase, and 2,3-dioxygenase enzymes were detected during the decolorization. In general, the present work concluded that the MO-1 was successfully degraded by C. aurelium RY06 and transformed to be maleic acid and to be isophtalic acid.

Objectives A high incidence of stalk rot disease of maize causes huge economic losses as well as deleterious effects on the environment and human health resulting from fungicide use. Against this background, the current study was established to evaluate the antagonistic efficacy of Trichoderma viride and Trichoderma harzianum strains against Fusarium proliferatum and Fusarium verticillioides strains, the most common causative agents of stalk rot disease of maize. Methods Dual culture assay was performed to determine the antagonistic efficacy of Trichoderma strains against some fusarial pathogens of maize. Mycoparasitic relationships of the antagonistic fungal strains against fungal pathogens were investigated using a slide culture technique. Furthermore, a food poisoning technique was performed to detect the antimycotic efficacy of Trichoderma culture filtrates against fusarial pathogens of maize. Antifungal activity of organic solvent extracts of T. harzianum and T. viride was evaluated using the disc diffusion method. GC–MS analysis was used to detect the active components of these extracts. Results and conclusion Trichoderma viride showed antagonistic activity against F. proliferatum and F. verticillioides with mycelial inhibition rates of 80.17% and 70.46%, while T. harzianum exhibited rates of 68.38% and 60.64%, respectively. The culture filtrates of T. viride and T. harzianum strains exhibited antifungal activity against F. verticillioides strain with suppressive rates of 56.7% and 32.2%, while the mycelial inhibition rates against F. proliferatum strain were 44.09% and 23.50%, respectively. Mycoparasitic action of T. harzianum strain against fusarial strains was detected, while no mycoparasitism was observed between T. viride and fungal pathogens. The fungicidal concentration of carbendazim fungicide against F. proliferatum was 2.00 ppm, while F. verticillioides strain exhibited resistance to carbendazim fungicide. Moreover, the acetonic extracts of T. viride and T. harzianum strains exerted the highest antifungal potency against F. proliferatum strain, recording minimum inhibitory concentrations of 0.25 and 0.50 mg/ml, respectively. The main bioactive constituents of the acetonic extracts of T. viride and T. harzianum strains were palmitic acid (22.87%) and acetic acid (21.36%), respectively. In conclusion, the antagonistic strains could be a potential source of novel biological fungicides, especially against carbendazim-resistant F. verticillioides strain, avoiding side effects of chemical fungicides.

Presently, the bioprocessing of agricultural residues to various bioactive compounds is of great concern, with the potential to be used as plant growth promoters and as a reductive of various diseases. Lycopersiconesculentum, one of the most consumed crops in the human diet, is attacked by Fusarium wilt disease, so the main aim is to biocontrol the pathogen. Several fungal species were isolated from decayed maize stover (MS). Trichodermaasperellum was chosen based on its organic acid productivity and was molecularly identified (GenBank accession number is MW195019). Citric acid (CA) was the major detected organic acid by HPLC. In vitro, CA of T.asperellum at 75% completely repressed the growth of Fusariumoxysporum f. sp. lycopersici (FOL). In vivo, soaking tomato seeds in CA enhanced the seed germination and vigor index. T. asperellum and/or its CA suppressed the wilt disease caused by FOL compared to control. There was a proportional increment of plant growth and yield, as well as improvements in the biochemical parameters (chlorophyll pigments, total phenolic contents and peroxidase, and polyphenol oxidase activities), suggesting targeting both the bioconversion of MS into CA and biological control of FOL.

Alkali activated concretes have emerged as a prospective alternative to conventional concrete wherein diverse waste materials have been converted as valuable spin-offs. This paper presents a wide experimental study on the sustainability of employing waste sawdust as a fine/coarse aggregate replacement incorporating fly ash (FA) and granulated blast furnace slag (GBFS) to make high-performance cement-free lightweight concretes. Waste sawdust was replaced with aggregate at 0, 25, 50, 75, and 100 vol% incorporating alkali binder, including 70% FA and 30% GBFS. The blend was activated using a low sodium hydroxide concentration (2 M). The acoustic, thermal, and predicted engineering properties of concretes were evaluated, and the life cycle of various mixtures were calculated to investigate the sustainability of concrete. Besides this, by using the available experimental test database, an optimized Artificial Neural Network (ANN) was developed to estimate the mechanical properties of the designed alkali-activated mortar mixes depending on each sawdust volume percentage. Based on the findings, it was found that the sound absorption and reduction in thermal conductivity were enhanced with increasing sawdust contents. The compressive strengths of the specimens were found to be influenced by the sawdust content and the strength dropped from 65 to 48 MPa with the corresponding increase in the sawdust levels from 0% up to 100%. The results also showed that the emissions of carbon dioxide, energy utilization, and outlay tended to drop with an increase in the amount of sawdust and show more the lightweight concrete to be more sustainable for construction applications.

A series of benzopyran-connected pyrimidine (1a–g) and benzopyran-connected pyrazole (2a–i) derivatives were synthesized via Biginelli reaction using a green chemistry approach. Cu(II)-tyrosinase was used as a catalyst in the synthesis of compounds 1a–g and 2a–i via the Biginelli reaction. The as-synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass spectroscopy, and elemental analysis. The as-synthesized compounds were screened for larvicidal and antifeedant activities. The larvicidal activity was evaluated using the mosquito species Culex quinquefasciatus, and the antifeedant activity was evaluated using the fishes of Oreochromis mossambicus. The compounds 2a–i demonstrated lethal effects, killing 50% of second instar mosquito larvae when their LD50 values were 44.17, 34.96, 45.29, 45.28, 75.96, and 28.99 μg mL−1, respectively. Molecular docking studies were used for analysis based on the binding ability of an odorant binding protein (OBP) of Culex quinquefasciatus with compound 2h (binding energy = −6.12 kcal mol−1) and compound 1g (binding energy = −5.79 kcal mol−1). Therefore, the proposed target compounds were synthesized via a green method using Cu(II)-enzyme as a catalyst to give high yield (94%). In biological screening, benzopyran-connected pyrazole (2h) was highly active compared with benzopyran-connected pyrimidine (1a–g) series in terms of larivicidal activity.

Streptomyces griseorubens E44G is a chitinolytic bacterium isolated from cultivated soil in Saudi Arabia (a hot, arid climatic region). In vitro, antifungal potential of S. griseorubens E44G was assessed against the phytopathogenic fungus, Fusarium oxysporum f. sp. lycopersici (the causative agent of the Fusarium wilt disease of tomato). An inhibition zone of 24 mm was recorded. The chitinolytic activity of S. griseorubens E44G was proved when the colloidal chitin agar plate method was used. A thermostable chitinase enzyme of 45 kDa molecular weight was purified using gel filtration chromatography. The optimum activity was obtained at 60 °C and pH 5.5. The purified enzyme has shown a very pronounced activity against the phytopathogenic fungus, F. oxysporum. The molecular characterization of the chitinase gene indicated that it consists of 1218 bp encoding 407 amino acids. The phylogentic analysis based on the nucleotide DNA sequence and the deduced amino acids sequence showed high similarity percentages with other chitinases isolated from different Streptomyces species. In the field evaluation, application of both S. griseorubens E44G treatments significantly increased all tested growth and yield parameters and decreased the disease severity compared with the infected-untreated tomato plants suggesting potential as a biocontrol agent.

The Sclerotium tuber rot fungus (Sclerotium rolfsii Sacc.) represents a serious problem for Jerusalem artichoke (JA) tubers during storage periods. The aim of this study was to investigate an alternative preservation method using a natural essential oil to inhibit the fungal growth, increase storability, and keep nutritive value of JA tubers under storage conditions. In vitro antifungal activity was assessed using two essential oils; caraway and spearmint at concentrations of 2, 3, 4 and 5 %. Among the tested treatments, caraway oil at 2 % resulted in complete inhibition of the fungal growth. In the storage experiment, two preservation methods were applied using caraway oil. In the first method, JA tubers were treated with caraway oil at 2 %, kept in perforated polyethylene bags and stored at 4 °C and 90 % relative humidity (RH). In the second method, JA tubers were treated with caraway oil at 2 %, kept between peat moss layers and stored at room temperature (25/10 °C, day /night) and 70 % RH. Comparing with the infected-untreated control, tubers infected with S. rolfsii and treated with caraway oil which kept in peat moss exhibited lower severity of Sclerotium tuber rot, sprouting percentage and weight loss. On the other hand, this treatment led to the highest dry matter and contents of carbohydrates, protein, inulin and total phenols as well as the activity of peroxidase and polyphenol oxidase enzymes. Based on the obtained results we recommend the use of caraway oil and peat moss when storing JA tubers at room temperature due to its eco-safety and saving of the cooling energy.

During preservation, Jerusalem artichoke (JA) tubers are subjected to deterioration by mold fungi under storage, which signifies a serious problem. A new blue mold (Penicillium polonium) was recorded for the first time on JA tubers. Penicillium mold was isolated, identified (morphologically, and molecularly), and deposited in GenBank, (MW041259). The fungus has a multi-lytic capacity, facilitated by various enzymes capable of severely destroying the tuber components. An economic oil-based procedure was applied for preserving and retaining the nutritive value of JA tubers under storage conditions. Caraway and clove essential oils, at a concentration of 2%, were selected based on their strong antifungal actions. JA tubers were treated with individual oils under storage, kept between peat moss layers, and stored at room temperature. Tubers treated with both oils exhibited lower blue mold severity, sprouting and weight loss, and higher levels of carbohydrates, inulin, and protein contents accompanied by increased levels of defense-related phytochemicals (total phenols, peroxidase, and polyphenol oxidase). Caraway was superior, but the results endorse the use of both essential oils for the preservation of JA tubers at room temperature, as an economic and eco-safe storage technique against the new blue mold.

This research investigates the possibility of grinding and burning bivalve clam seashells to produce seashell ash powder. This ash is used to partially replace cement by 5, 10, 15 and 20% by weight. These mixes are tested and compared with a SC0 that has 0% seashell ash powder (SC0). The fresh and hardened properties of all mixes are studied through a variety of tests, including: slump, unit weight, compressive strength and splitting tensile strength. The durability of seashell concrete cubic specimens is studied by immersion in 5% NaOH(aq) and MgSO4(aq) solutions. The addition of thermally treated seashells increased the calcium hydroxide content. The results also show that the compressive strength of the 5% replacement is slightly higher than the SC0 at 28 and 90 days of age, while the tensile strength is higher than the standard for the 5% and 10% of replacement at 7 and 28 days. Furthermore, the slump test value generally increases with increasing the percentage of replacement. The highest durability against sulfate and alkaline attacks is obtained with 5% replacement of cement with seashells which reported the lowest decrease in weight and the highest compressive strength after immersion in 5% NaOH(aq) and MgSO4(aq) solutions. The 5% replacement mix is the optimum percentage of replacement. Therefore, this study recommends replacing cement with 5% seashell cement. This research investigates the possibility of grinding and burning bivalve clam seashells to produce seashell ash powder. This ash is used to partially replace cement by 5, 10, 15 and 20% by weight. These mixes are tested and compared with a SC0 that has 0% seashell ash powder (SC0). The fresh and hardened properties of all mixes are studied through a variety of tests, including: slump, unit weight, compressive strength and splitting tensile strength. The durability of seashell concrete cubic specimens is studied by immersion in 5% NaOH(aq) and MgSO4(aq) solutions. The addition of thermally treated seashells increased the calcium hydroxide content. The results also show that the compressive strength of the 5% replacement is slightly higher than the SC0 at 28 and 90 days of age, while the tensile strength is higher than the standard for the 5% and 10% of replacement at 7 and 28 days. Furthermore, the slump test value generally increases with increasing the percentage of replacement. The highest durability against sulfate and alkaline attacks is obtained with 5% replacement of cement with seashells which reported the lowest decrease in weight and the highest compressive strength after immersion in 5% NaOH(aq) and MgSO4(aq) solutions. The 5% replacement mix is the optimum percentage of replacement. Therefore, this study recommends replacing cement with 5% seashell cement.

Globally, plant viral infection is one of the most difficult challenges of food security, where considerable losses in crop production occur. Nanoparticles are an effective control agent against numerous plant pathogens. However, there is limited knowledge concerning their effects against viral infection. In the present study, the green synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous leaf extract of Mentha spicata was achieved. X-ray diffraction patterns confirmed the crystalline nature of the prepared ZnO NPs. Dynamic light scattering and scanning electron microscopy analyses revealed that the resultant ZnO NPs were spherical in shape with a particle size ranged from 11 to 88 nm. Fourier transmission infrared spectroscopy detected different functional groups, capping and stability agents, and showed Zn-O bond within wavenumber of 487 cm&minus, 1. Under greenhouse conditions, the antiviral activity of biological synthesized ZnO NPs (100 &micro, g/mL) against Tobacco mosaic virus (TMV) was evaluated. The double foliar application of the prepared ZnO NPs, 24 h before and 24 h after TMV-inoculation, was the most effective treatment that showed a 90.21% reduction of viral accumulation level and disease severity. Additionally, the transcriptional levels of PAL, PR-1 (salicylic acid marker gene), CHS, and POD genes were induced and up-regulated in all ZnO NPs treated plants. Notably, the results exhibited that aqueous extract of Mentha spicata was an effective reducing agent for the green synthesis of ZnO NPs, which showed significant antiviral activity. Finally, the detected protective and curative activity of ZnO NPs against TMV can encourage us to recommend its application for plant viral disease management. To our knowledge, this is the first study describing the antiviral activity of the green synthesized ZnO NPs.

The high incidence of Candidal vulvovaginitis (CVV) among pregnant women and its treatment during pregnancy is a challenge as the antifungal therapy is associated with foetal abnormalities. Additionally, various Candida species exhibit resistance to commonly used antifungal agents. Hence, there is a need to develop new therapeutic strategies against CVV. In the present study, we have evaluated the antifungal activity of cinnamon extracted by four solvents with different degrees of polarity against common Candida pathogens. The ethyl acetate extract of cinnamon was the most effective solvent extract and exhibited the highest antifungal activity against Candida albicans , Candid atropicalis and Candida glabrata , with an inhibition zone diameter of 32.47, 32.1 and 16.7 mm respectively. GC-MS revealed that cinnamon ethyl acetate extract comprised of 1-phenylpropene-3.3-diol diacetate (68.5%), eugenol (11.6%), cinnamic acid (8.2%), cinnamaldehyde (6.1%) and 6-ethyl-3,4- dimethylphenol (5.4%). Minimum inhibitory concentration of cinnamon ethyl acetate extract against C. albicans and C. tropicalis was 0.5 mg/disc, while that against C. glabrata was 1 mg/disc. Minimum fungicidal concentration of cinnamon ethyl acetate extract against C. tropicalis was 1 mg/disc, while that against C. albicans and C. glabrata was 2 mg/disc respectively.

Antagonistic actinomycete strains isolated from the environment are valuable tools for an eco-friendly, healthy, and safe control of phytopathogenic fungi. We have evaluated the culture filtrate of Streptomyces griseorubens E44G, an actinomycete strain isolated from soil, on the growth and ultrastructure of hyphal cells of the phytopathogenic fungus Fusarium oxysporum f. sp. lycopersici, the causal agent of Fusarium wilt disease of tomato. The effect of the Streptomyces culture filtrate on some of the carbohydrate fractions in the hyphal cell of the pathogen using gold-labeled lectin complexes was also elucidated. Of the concentrations of S. griseorubens E44G culture filtrate tested, the highest (400 μL) had the most potent antifungal effect on the mycelial growth of the fungus. At this concentration, some changes in the morphology of the fungal hyphae were observed by scanning electron microscopy, and a number of dramatic changes in the ultrastructure of the hyphal cells of the fungus were observed by transmission electron microscopy. Ultracytochemical localization of carbohydrate fractions of the hyphal cell of the fungus revealed the presence of a very high quantity of chitin in the cell wall which was digested following exposure to the culture filtrate of S. griseorubens E44G, indicating the presence of a chitinase enzyme in that filtrate. The ultracytochemical investigations also indicated the presence of mannose, glucose, and galactose in the fungal cell wall, as well as the absence of glucosides. Moreover, the fungal cell cytoplasm contained glucosides and galactose but not chitin. These results confirm that the chitinase enzyme was produced by S. griseorubens E44G and that this enzyme may play a role in the potential of this strain as an antifungal agent against F. oxysporum f. sp. lycopersici.