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The thermophilic fungus Gymnascella thermotolerans GTE-21 produces a significant amount of both volatile and nonvolatile compounds with potent antifungal and anticancer properties. Gas chromatography-mass spectrometry (GC-MS) was utilized to identify 14 volatile organic compounds (VOCs) released by G. thermotolerans. The most predominant compound identified was diisooctyl phthalate, constituting 71.99% of the total VOCs, followed by phenol, 2-methoxy-4-(2-propenyl) at 7.12%. The GTE-21's VOCs demonstrated significant antifungal growth inhibition activity of 42.5% against Fusarium solani and 39.03% against Alternaria alternata. Additionally, GTE-21's crude extract exhibited substantial antibacterial effects, evidenced by inhibition zones of 1.5 cm against S. epidermidis, 1.4 cm against C. ciferrii, and 1.3 cm against S. aureus. The CHR2RClR2R:MeOH (1:1) fraction was more effective against human pathogens, producing the largest zones of inhibition of 1.1 and 1.03 cm against S. epidermidis and C. ciferrii, respectively. The evaluation of GTE-21's antifungal activity using the Evans blue assay showed that fungal spores treated with GTE-21's crude extract exhibited 96.2% inhibition at a concentration of 25 mg/ml. Similarly, the fractions CH2Cl2:MeOH (1:1) and CH2Cl2:MeOH (9:1) demonstrated spore inhibition rates of 96.3% and 94.3%, respectively. The EtOAc crude extract demonstrated pronounced cytotoxic effects against the SKOV-3 and MDA-MB-231 cancer cell lines. For SKOV-3, cell viability decreased to 3.40% and 0.47% at concentrations of 50 and 100 μL, respectively. In the case of MDA-MB-231, cell viability was reduced to 0.19% at both 50 and 100 μL concentrations. [ABSTRACT FROM AUTHOR]

Desert plant vegetation plays an important role in natural habitat, as its growth depends largely on germination of seeds. The growth of individual plants depends on how the seed germination responds to environmental conditions. Seeds of ten desert species were collected at the Red Sea road in Egypt. The purpose of this study is to provide a clear picture of some important factors (temperature, scarification, and soaking treatment) on the germination of the collected seeds. The temperature effect was found to play the greatest role in the germination rate for most of the species' seeds between 25° and 30°. Reseda pruinosa and Ochradenus baccatus experienced the highest percentages of seed germination at 25° which were 100% and 93% respectively followed by Schouwia purpurea and Cotula cinerea which their seeds germination was 87% while at 30°, R. pruinosa and S. purpurea represented the highest two values of germination which were 93% and 80% respectively. S. purpurea showed significant response to concentrated nitric acid treatment in both 30s and 1.0min. which were 100% and 87% respectively, while Asphodelus fistulosus made up about 65% germination. R. pruinosa showed slight growth of around 7% after soaking in boiling water. [ABSTRACT FROM AUTHOR]

The fruit rot disease of sweet melon is responsible for serious of economic crop losses that have occurred sporadically in Aswan, Egypt recently. The symptoms appeared as water-soaking lesion which advanced to the rotting of the fruit surface. White mycelial mats with brown color inside appear on the lesion at the surface of the fruit. Disease symptoms, morphological and mycological characteristics, pathogenicity and molecular identification, indicated as Fusarium solani, are the disease causative. When healthy fruits of sweet melon sprayed with spore suspension of the isolated F. solani, the disease symptoms appeared as white spot, which enlarged and turned brown. Dual culture techniques showed that the endophytic fungi, Aspergillus terreus, Fusarium solani and Penicillium verrucosum isolated from the medicinal plant Solenostemma arghel inhibited the pathogen growth in variable levels. The extract of ethyl acetate of the endophytic fungal was found to be active against Fusarium solani. The ethyl acetate fractions of Penicillium verrucosum inhibited the pathogen growth by 47% while A. terreus, and F. solani showed inhibition percentage of 45% and 40%, respectively [ABSTRACT FROM AUTHOR]

Drought and heat stresses are major constraints to agriculture worldwide, reducing crop productivity and affecting global food security. Two okra cultivars (Japanese and Egyptian) with different physiological attributes were crossbred for producing F1 hybrids. All cultivars and their hybrids were evaluated for drought stress tolerance at two water regimes (12% and 2%). At limited water condition, photosynthesis and stomatal conductance tended to decrease in Egyptian parent and Japanese ×Egyptian hybrid while transpiration rate showed no significant changes in both parents and F1 hybrids. Maximum quantum yield of PSII (Fv/Fm) ratio was decreased with decreasing soil moisture content in Japanese cultivar, E×J and J×E hybrids with mean value of (0.14, 0.16 and 0.15, respectively). Chlorophyll content in both parents and their hybrids was decreased under severe drought stress. Significant high activity levels of the anti-oxidative enzymes, peroxidase (POX) and superoxide dismutase (SOD) was observed in water-stressed plants than in well-watered (12% water regime) plants. The highest activity of POX was recorded in E×J hybrid (234.9 U/g FW) and the highest activity of SOD was found in Japanese cultivar (18.69 U/g FW). Accumulation of proline content under drought severity stress in both hybrids (E×J and J×E) was recorded (16.7 and 10.4 mg/g DW, respectively). The performance of E×J hybrid was more prominent than parents because of the strong antioxidant defence system and accumulation of higher proteins, proline and chlorophyll content than other cultivars. [ABSTRACT FROM AUTHOR]

Background and Objectives: The use of endophytic fungi for management of phenol residue in paper and pulp industries has been shown as cost-effective and eco-friendly approach. In this study, isolation of endophytic fungi from roots, stems, and leaves of Hibiscus sabdariffa was conducted. Additionally, the isolated fungi were examined for their ability to degrade phenol and its derivatives in paper and pulp industrial samples, using different growth conditions. Materials and Methods: Out of 35 isolated endophyitc fungi, 31 were examined for their phenol biodegradation capacity using Czapek Dox broth medium containing Catechol and Resorcinol as a sole carbon source at final concentrations of 0.4, 0.6 and 0.8%. Results: A total of 35 fungal species belonging to 18 fungal genera were isolated and identified from different parts of H. sabdariffa plants. All strains have the capability for degrading phenol and their derivatives with variable extents. The optimum condition of degrading phenol in paper and pulp effluent samples by Fusarium poae11r7 were at pH 3-5, temperature at 28-35°C, good agitation speed at no agitation and 100 rpm. Conclusion: All endophytic fungal species can utilize phenol and its derivatives as a carbon source and be the potential to degrade phenol in industrial contaminants. [ABSTRACT FROM AUTHOR]

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In this study, we investigated the potential role of the karrikin receptor KARRIKIN INSENSITIVE2 (KAI2) in the response of Arabidopsis seedlings to high-temperature stress. We performed phenotypic, physiological and transcriptome analyses of Arabidopsis kai2 mutants and wild-type (WT) plants under control (kai2_C and WT_C, respectively) and 6- and 24-h heat stress conditions (kai2_H6, kai2_H24, WT_H6 and WT_H24, respectively) to understand the basis for KAI2-regulated heat stress tolerance. We discovered that the kai2 mutants exhibited hypersensitivity to high-temperature stress relative to WT plants, which might be associated with a more highly increased leaf surface temperature and cell membrane damage in kai2 mutant plants. Next, we performed comparative transcriptome analysis of kai2_C, kai2_H6, kai2_H24, WT_C, WT_H6 and WT_H24 to identify transcriptome differences between WT and kai2 mutants in response to heat stress. K-mean clustering of normalized gene expression separated the investigated genotypes into three clusters based on heat-treated and non-treated control conditions. Within each cluster, the kai2 mutants were separated from WT plants, implying that kai2 mutants exhibited distinct transcriptome profiles relative to WT plants. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed a repression in 'misfolded protein binding', 'heat shock protein binding', 'unfolded protein binding' and 'protein processing in endoplasmic reticulum' pathways, which was consistent with the downregulation of several genes encoding heat shock proteins and heat shock transcription factors in the kai2 mutant versus WT plants under control and heat stress conditions. Our findings suggest that chemical or genetic manipulation of KAI2 signaling may provide a novel way to improve heat tolerance in plants., (© The Author(s) 2022. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)