Plant growth-promoting endophytic bacteria can stimulate the growth, nutrient acquisition, symbiotic performance and stress tolerance of chickpea plants under saline soil conditions. The aim of this study was to investigate the stress-adaptive mechanisms of chickpea plants mediated by Bacillus subtilis (BERA 71) under saline conditions. Inoculation with BERA 71 enhanced plant biomass and the synthesis of photosynthetic pigments and reduced the levels of reactive oxygen species (ROS) and lipid peroxidation in plants under conditions of stress. Furthermore, the activities of ROSscavenging antioxidant enzymes (superoxide dismutase, peroxidase, catalase and glutathione reductase), the levels of non-enzymatic antioxidants (ascorbic acid and glutathione) and the total phenol content were increased in stressed plants during bacterial association. The bacteria decreased sodium accumulation and enhanced the nitrogen, potassium, calcium and magnesium content in the plants. The suppression of ROS generation and of lipid peroxidation and the accumulation of proline in BERA-71-inoculated plants enhanced the membrane stability under salinity stress and non-stress conditions.

Cheeseweed mallow ( Malva parviflora L.) was used to biosynthesize silver nanoparticles. The biosynthesized silver nanoparticles were classified by UV–vis Spectroscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). The shape and size distribution were visualized by Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FE-SEM), and Zeta potential analysis. The chemical composition of M. parviflora leaf extract was identified by Gas Chromatography and Mass Spectroscopy (GC/MS). Finally, in vitro antifungal assay was done to assess the potential of biosynthesized silver nanoparticles and crude leaf extract of M. parviflora for inhibiting the mycelial growth of phytopathogenic fungi. The UV–vis analysis manifests the formation of silver nanoparticles. FTIR analysis established that chemicals of the leaf extract stabilized the biosynthesized silver nanoparticles by binding with the free silver ions. The TEM, FE-SEM and zeta potential analyzer confirmed that the biosynthesized silver nanoparticles were mostly spherical with an average diameter of 50.6 nm. The biosynthesized silver nanoparticles and leaf extract of M. parviflora effectively mitigate the mycelial growth of Helminthosporium rostratum, Fusarium solani, Fusarium oxysporum , and Alternaria alternata. The maximum reduction in mycelial growth by biosynthesized nanoparticles was observed against H. rostratum (88.6%). Whereas, the leaf extract of M. parviflora was most effective against F. solani (65.3%). Thus, the biosynthesis of nanoparticle assisted by M. parviflora is a feasible and eco-friendly method for the synthesis of silver nanoparticles. Further the silver nanoparticles and leaf extract of M. parviflora could be explored for the development of the fungicide.

The green biosynthesis of nanoparticles by plant extracts is an attractive and promising technique for medicinal applications. In the current study, we chose one of the daisy plants, Aaronsohnia factorovskyi (which grows in the Najd region, Saudi Arabia), to investigate its anti-microbial efficacy, in combination with silver nanoparticles. The biosynthesized nanoparticles were evaluated for antibacterial activity against Staphylococcus aureus, Bacillussubtilis (Gram-positive), Pseudomonas aeruginosa, and Escherichia coli, (Gram-negative) using the disc diffusion method, while the antifungal activity was assessed against Fusarium oxysporum, Fusarium solani, Helminthosporiumrostratum, and Alternariaalternata. The potential phytoconstituents of the plant extracts were identified by Fourier-transform infrared spectroscopy (FT-IR) techniques, the Field emission scanning electron microscopy (FE-SEM), Chromatography/Mass Spectrometry (GC-MS) techniques, and Zeta potential analysis. The current study revealed the ability of the tested plant extract to convert silver ions to silver nanoparticles with an average diameter of 104–140 nm. Biogenic Aaronsohnia factorovskyi-silver nanoparticles (AF-AgNPs) showed significant antibacterial activity against Staphylococcus aureus with inhibition zone diameter to 19.00 ± 2.94 mm, and antifungal activity against Fusarium solani, which reduced the growth of fungal yarn to 1.5 mm. The innovation of the present study is that the green synthesis of NPs, which is simple, cost-effective, provides stable nano-materials, and can be an alternative for the large-scale synthesis of silver nanoparticles.

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Grape seed extract (GSE) is a natural source of polyphenolic compounds and secondary metabolites, which have been tested for their possible antimicrobial activities. In the current study, we tested the antibacterial and antifungal activities of aqueous GSE and the biosynthesized silver nanoparticles loaded with GSE (GSE-AgNPs) against different pathogens. The biosynthesized GSE-AgNPs were assessed by UV spectroscopy, dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and gas chromatography/mass spectrometry (GC/MS). The antimicrobial activities were assessed against different bacterial and fungal species. DLS analysis showed that GSE-AgNPs had a Z-Average of 91.89 nm while UV spectroscopy showed that GSE-AgNPs had the highest absorbance at a wavelength of ~415 nm. FTIR analysis revealed that both of GSE and GSE-AgNPs consisted of different functional groups, such as hydroxyl, alkenes, alkyne, and aromatic rings. Both FE-SEM and TEM showed that GSE-AgNPs had larger sizes and rough surfaces than GSE and AgNO3. The results showed significant antimicrobial activities of GSE-AgNPs against all tested species, unlike GSE, which had weaker and limited effects. More studies are needed to investigate the other antimicrobial activities of GSE.

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Currently, the bioremediation of petroleum hydrocarbons employs microbial biosurfactants because of their public acceptability, biological safety, and low cost. These organisms can degrade or detoxify organic-contaminated areas, such as marine ecosystems. The current study aimed to test the oil-biodegradation ability of the fungus Drechslera spicifera, which was isolated from contaminated soil samples in Riyadh, Saudi Arabia. We used hydrocarbon tolerance, scanning electron microscopy, DCPIP, drop-collapse, emulsification activity, recovery of biosurfactants, and germination assays to assess the biodegradation characteristics of the D. spicifera against kerosene, crude, diesel, used, and mixed oils. The results of DCPIP show that the highest oxidation (0.736 a.u.) was induced by crude oil on the 15th day. In contrast, kerosene and used oil had the highest measurements in emulsification activity and drop-collapse assays, respectively. Meanwhile, crude and used oils produced the highest amounts of biosurfactants through acid precipitation and solvent extraction assays. Furthermore, the biosurfactants stimulated the germination of tomato seeds by more than 50% compared to the control. These findings highlight the biodegradation ability of D. spicifera, which has been proven in the use of petroleum oils as the sole source of carbon. That might encourage further research to demonstrate its application in the cleaning of large, contaminated areas.

This study was designed to investigate the potential defensive strategy of Sana Makki extract (SME) against Cd-induced in vivo nephrotoxicity and its underlying mechanisms. Male albino rats were used in a thirty days study comparing control, SMEtreated, CdCl 2 -treated, and combined SME and Cd treatment. Pre-treatment with SME signifi cantly reduced serum kidney biomarkers (urea and creatinine), the concentration of renal KIM-1, and kidney index values. Additionally, SME also attenuated CdCl 2 -induced oxidative and nitrosative stress in renal tissue; signifi cantly reducing malondialdehyde (MDA) and nitric oxide (NO) concentrations and signifi cantly increasing antioxidant enzymes in kidney tissue. Molecularly, SME signifi cantly upregulated antioxidant gene expression (SOD2, GR, GPx1, and CAT) caused by Cd. Notably, the augmented mRNA expression of nuclear-related factor 2 (Nrf2) by Cd was enhanced by SME administration. SME markedly suppressed the Cd-induced rise in pro-infl ammatory cytokines. The combination of Cd and SME relieved the Cd-induced apoptotic damage by enhancing Bcl2 and suppressing Bax and Cas-3 levels in renal tissue. The renal tissue histoarchitecture confi rmed the biochemical and molecular fi ndings. Collectively, our data indicate that SME can counteract Cd-induced renal intoxication through anti-oxidative, antiinfl ammatory, and anti-apoptotic mechanisms.