Developing and applying a novel plant growth–promoting agent (PGPA; a micronutrient-amino acid chelated compound developed from autolysis yeast cells) in alleviating salt stress toxicity can be the best alternative option environmentally and economically. High-performance liquid chromatography (HPLC) showed that the assembled PGPA is rich in nucleobases than yeast extract (> 56-fold). This study, as a first investigation, was aimed to evaluate PGPA’s potential role in reducing oxidative injury induced by salt stress. Barley (Hordeum vulgare L. cv. Giza 123) plants were grown under non-saline or saline conditions (6.0 and 12.0 dS m−1) with and without PGPA foliar application. The PGPA application mitigated salt-induced oxidative stress by enhancing the activity of superoxide dismutase, catalase, guaiacol peroxidase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, glutathione reductase, glutathione peroxidase, and glutathione S-transferase, as well as the content of ascorbate, glutathione, proline, and glycinebetaine. Moreover, PGPA protected salt-stressed plants from the deleterious effects of methylglyoxal by up-regulating the glyoxalase enzymes activity. The PGPA alleviated membrane damage by decreasing reactive oxygen species (ROS) accumulation, lipid peroxidation, protein oxidation, electrolyte leakage, and NADP+ content. The protection of photosynthesis by PGPA was closely associated with the improved chlorophyll fluorescence parameters, leaf water content, membrane stability index, and NADPH content. The PGPA-treated plants also exhibited higher stomatal conductivity together with improved transpiration and photosynthetic rates under saline conditions. Overall, PGPA regulated the antioxidant machinery, glyoxalase system, and photosynthetic capacity, implying that it plays a critical role in salt stress mitigation. Therefore, it could be a useful agent to alleviate the harmful effects of salinity stress.

Potential biologically active derivatives of the curcumin were prepared by the cyclocondensation reaction cyclohexanone 2, imino pyrimidine 3, pyrmidinones 4, thiopyrimidine 6 and pyranone 5, 7 when treated with acetylacetone, guanidine, ureaethylcyanoacetate, thiourea and ethylacetoacetate, respectively. The structures of compounds (2-7) were elucidated by means of microanalysis as well as spectral measurements such as IR, H-NMR, MS. The anti-diabetic potential of curcumin derivatives were evaluated by assessing amylase inhibition assay, also inhibition of histamine release activity of curcumin derivatives were assessed by U937 human monocytes. The results for amylase inhibition activity revels that the curcumin inhibits α-amylase in a concentration dependent manner. Compounds 4 and 5 exhibited significant inhibitory activity against amylase enzyme and was comparable with that of acrabose. Also, compounds 5, 6 and 7 exhibited significant inhibitory activity against histamine. Our results concluded that curcumin pyrmidinones and pyranone derivatives have highly effects as anti-diabetic and anti-histamine activities.

Background: The present study investigated the antifungal activity and mode of action of four Olea europaea leaf extracts, Thymus vulgaris essential oil (EO), and Boswellia carteri EO against Fusarium oxysporum. Methods:Fusarium oxysporum Lactucae was detected with the internal transcribed spacer (ITS) region. The chemical compositions of chloroform and dichloromethane extracts of O. europaea leaves and T. vulgaris EO were analyzed using GC-MS analysis. In addition, a molecular docking analysis was used to identify the expected ligands of these extracts against eleven F. oxysporum proteins. Results: The nucleotide sequence of the F. oxysporum Lactucae isolate was deposited in GenBank with Accession No. MT249304.1. The T. vulgaris EO, chloroform, dichloromethane and ethanol efficiently inhibited the growth at concentrations of 75.5 and 37.75 mg/mL, whereas ethyl acetate, and B. carteri EO did not exhibit antifungal activity. The GC-MS analysis revealed that the major and most vital compounds of the T. vulgaris EO, chloroform, and dichloromethane were thymol, carvacrol, tetratriacontane, and palmitic acid. Moreover, molecular modeling revealed the activity of these compounds against F. oxysporum. Conclusions: Chloroform, dichloromethane and ethanol, olive leaf extract, and T. vulgaris EO showed a strong effect against F. oxysporum. Consequently, this represents an appropriate natural source of biological compounds for use in healthcare. In addition, homology modeling and docking analysis are the best analyses for clarifying the mechanisms of antifungal activity.