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Β-glucosidase (BGLs) act synergistically with endoglucanases and exoglucanases and then are of great interest for biomass conversion into bioethanol. Thus, the aim of the current study is to produce a recombinant β-glycosidase from Moniliophtora perniciosa expressed in Escherichia coli cells. Enzyme coding sequence expression was confirmed through Sanger sequencing after using wheat bran (WB) and carboxymethylcellulose (CMC) as fungal growth media. Synthetic gene betaglyc-GH1 with optimized codons for E. coli expression was cloned in pET-28a. β-glucosidase recombinant (GH1chimera) was purified using a nickel column and its identity was confirmed through mass spectrometry. The recombinant enzyme presented an apparent molecular mass of 53.23 kDa on SDS-PAGE. Recombinant β-glucosidase has shown hydrolytic activity using p-nitrophenyl-β-D-glycopyranoside (pNPG) as substrate and maximum activity at pH 4.6 and 65 °C. Thus, the results indicate that the application of the GH1chimera in the hydrolysis of lignocellulosic materials to obtain glucose monomers can be efficient.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-024-04128-x.

Silver nanoparticles (AgNPs) have attracted increasing attention in nanomedicine, with versatile applications in drug delivery, antimicrobial treatments, and cancer therapies. While chemical synthesis remains a common approach for AgNP production, ensuring environmental sustainability requires a shift toward eco-friendly, "green" synthesis techniques. This article underscores the promising role of plant extracts in the green synthesis of AgNPs, highlighting the importance of their natural sources and diverse bioactive compounds. Various characterization methods for these nanomaterials are also reviewed. Furthermore, the anticancer potential of green AgNPs (Gr-AgNPs) is examined, focusing on their mechanisms of action and the challenges to their clinical implementation. Finally, future directions in the field are discussed.

A total of 151 genotypes of durum and bread wheat exhibiting symptoms of stunting and bushy growth, leaf yellowing, and drying of clumps were recorded at ICAR-IARI Regional Station, Indore, Madhya Pradesh, India from 2016 to 2018. The disease incidence was recorded more in durum wheat genotypes as compared to bread wheat genotypes. The presence of any virus, bacterial, and fungal pathogens was ruled out by applying cultural growth and electron microscopy. However, association of phytoplasmas presence was confirmed in 142 (out of 151) durum and bread wheat genotypes by employing PCR primer pairs of 16S rRNA, leuS and secA genes. The sequence analysis of all the genes and in silico RFLP analysis of 16S rDNA sequences of wheat phytoplasma strains identified them as rice yellow dwarf group (16SrXI-B) and Bermuda grass white leaf group (16SrXIV-A). Two symptomatic weed species (Parthenium hysterophorus and Cleome gynandra) tested positive for 16SrXI-B phytoplasma subgroup and four weed species (Cynodon dactylon, Digitaria sanguinalis, Euphorbia hirta and Rhynchosia minima) for 16SrXIV-A phytoplasma subgroup growing in and around wheat fields. Six hopper species identified from symptomatic wheat fields were also analyzed for phytoplasma presence. Three hopper species viz., Sogatella furcifera, Balclutha rubrostriata, and Exitianus indicus were tested positive to phytoplasmas in 16SrXIV group, while Sogatella kolophon, Cofana unimaculata, and Maiestas sp. tested positive to 16SrXI group of phytoplasmas in nested PCR assays. Transmission assays revealed that S. furcifera and B. rubrostriata successfully transmitted the 16SrXIV-A strain from infected wheat to healthy wheat plants; however, C. unimaculata was able to transmit 16SrXI-B subgroup from infected wheat to healthy wheat plants under glasshouse conditions. A variation in phytoplasma associated disease incidence was recorded on wheat genotypes in different years and was also found positively correlated with temperature, humidity, and hopper population. The identification of similar phytoplasma strains (16SrXI and 16SrXIV group) from wheat, weeds, and hoppers indicated potential risk of transmission of these strains to wheat genotypes and other agricultural crops, which needs further investigations on epidemiological aspects.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-024-04114-3.

Clostridioides difficile, a zoonotic pathogen causing enteric diseases in different animals and humans. A comprehensive study on the presence of toxin genes and antimicrobial resistance genes based on genome data of C. difficile in animals is scanty. In the present study, a total of 15 C. difficile isolates were recovered from dogs and isolates with toxin genes (D1, CD15 and CD26) along with two other non-toxigenic strains (CD28, CD32) were used for whole genome sequencing and comparative genomics. Sequence type-based clustering was noted in the whole genome phylogeny with 4 known multi-locus sequence typing (MLST) clades namely I, II, IV, and V and a cryptic clade. ST11 and ST54 were reported for the 2^nd time worldwide in dogs. Out of 109 genomes used in the study, 29 genomes were predicted with all four toxin genes (toxA, toxB, cdtA, cdtB) while 22 did not have any of the toxin genes. ST11 of MLST clade V had the maximum number of 46 genomes predicted with at least one toxin gene. Among the genomes sequenced in this study, CD26 had a maximum of 5 AMR genes (aac(6')-aph(2″), ant(6)-Ia, catP, erm(B)_18, and tet(M)_11) and CD15 was predicted with 2 AMR genes (aac(6')-aph(2″), erm(B)_18). Tetracycline resistance genes were predicted most in the ST11 genome. Of the 22 non-toxigenic strains, 9 genomes (ST48 = 5, ST3 = 2, ST109 = 1, ST15 = 1) were predicted with a minimum of one AMR gene. Pangenome analysis indicated that the Bpan value is 0.12 showing that C. difficile has an open pangenome structure. This indicates that the organism can evolve by the addition of new genes. This study reports the circulation of clinically important ST11 and multidrug-resistant non-toxigenic strains among animals.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-024-04102-7.

This study investigated the antagonistic activity of Trichoderma asperellum against chickpea Fusarium wilt through in vitro and in vivo experiments. The dual culture test showed that Trichoderma had a significant inhibitory effect on the growth of the tested Fusarium isolates, with an inhibition rate ranging from 71.33% to 80.66%. The volatile and non-volatile metabolites produced by Trichoderma also showed antagonistic effects, with a growth inhibition rate ranging from 47.33% to 51.33% and a colonization rate ranging from 60% to 67%. In vivo experiments demonstrated that treating chickpea seeds with Trichoderma asperellum 48 h after inoculation with Fusarium significantly enhanced chickpea growth compared to seeds inoculated with Fusarium alone. Arial part length enhancement ranged between 69.3% and 92,19% while root length increased by 61,9% and 127%, this implied a significant improvement in biomass. These findings highlight Trichoderma's potential in controlling chickpea Fusarium wilt and enhancing plant growth, making it an environmentally friendly method in sustainable agriculture and crop protection.

In this study, it was aimed to examine the neuroprotective effects of ethanolic extracts of Chlorella variabilis YTU.ANTARCTIC.001 and Chlorella pyrenoidosa OZCIMEN.001 microalgae that were isolated from Antarctica in a H₂O₂-induced oxidative stress model using SH-SY5Y cell line. In this context, first, Antarctic microalgae were cultivated and characterized. It was determined that C. pyrenoidosa and C. variabilis had specific growth rates of 0.093 and 0.097 day^-1, respectively, and doubled their cell concentration in 7 days. With the antioxidant and phenolic content analysis, it was found that 1 mg/mL C. pyrenoidosa and C. variabilis ethanolic extracts had 33-37% radical scavenging activity and 102-107 mg GAE/mg extract phenolic content, respectively. Then, the cytotoxic effects of the microalgae extracts on SH-SY5Y cells were assessed across a concentration range of 6.25-125 µg/mL. The results indicated a concentration-dependent effect on cell viability, with no observed cytotoxicity within the tested range. Notably, the highest neuroprotective activity was recorded with C. variabilis extract at a concentration of 75 µg/mL, which maintained cell viability at 73.7% ± 0.3. These findings showed the significant neuroprotective potential of C. pyrenoidosa and C. variabilis ethanolic extracts, attributed to their substantial antioxidant properties and non-cytotoxic nature at effective concentrations. The promising neuroprotective efficacy of these extracts highlights their potential for therapeutic applications in neurodegenerative disease prevention and treatment.

This study aimed to address the gap in knowledge regarding the fate of foodborne pathogens within agro-ecosystems. It specifically focused on the surrogate microorganism Clostridium sporogenes, which was introduced into lettuce-producing environments via surface and spray irrigation methods, respectively. The concentration of C. sporogenes in the rhizosphere, phyllosphere, and non-rhizosphere soil was quantified by quantitative polymerase chain reaction (qPCR) over a 42-day trial. The surface irrigation method exhibited a more noticeable contamination effect on the soil environments, compared to the phyllosphere. The results indicated a noticeable increase in C. sporogenes concentrations during the initial 22 days, with a 10.4-fold rise (0.39-4.05 log copy numbers/g soil) in the rhizosphere and 1.9-fold increase (2.97-5.59 log copy numbers/g soil) in the non-rhizosphere. However, concentrations in both soil environments subsequently decreased, falling below the initial inoculum concentration by the end of the trial. In contrast, the spray irrigation method resulted in most of the contamination being localised on the lettuce phyllosphere, with a high C. sporogenes concentration of 9.09 log copy numbers/g leaves on day 0. This concentration exponentially decreased to a minimal 0.019 log copy numbers/g leaves by day 32. Although concentrations in both soil environments decreased over time, trace concentrations of C. sporogenes were detectable at the end of the trial, posing a potential hazard to the microbiological safety of postharvest produce. These findings shed light on the dynamics of C. sporogenes in agro-ecosystems and underscore the importance of irrigation practices that ensure the safety of those who consume fresh produce.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-024-04069-5.

Crude oil contamination has been widely recognized as a major environmental issue due to its various adverse effects. The use of inhabitant microorganisms (native to the contaminated sites) to detoxify/remove pollutants owing to their diverse metabolic capabilities is an evolving method for the removal/degradation of petroleum industry contaminants. The present study deals with the exploitation of native resident bacteria from crude oil contaminated site (oil exploration field) for bioremediation procedures. Fifteen (out of forty-four) bioremediation-relevant aerobic bacterial strains, belonging to the genera of Bacillus, Stenotrophomonas, Pseudomonas, Paenibacillus, Rhizobium, Burkholderia, and Franconibacter, isolated from crude oil containing sludge, have been selected for the present bioremediation study. Crude oil bioremediation performance of the selected bacterial consortium was assessed using microcosm-based studies. Stimulation of the microbial consortium with nitrogen or phosphorous led to the degradation of 60-70% of total petroleum hydrocarbon (TPH) in 0.25% and 0.5% crude oil experimental sets. CO₂ evolution, indicative of crude oil mineralization, was evident with the highest evolution being 28.6 mg mL^-1. Ecotoxicity of treated crude oil-containing media was assessed using plant seed germination assay, in which most of the 0.25% and 0.5% treated crude oil sets gave positive results thereby suggesting a reduction in crude oil toxicity.

We investigated the hypoglycemic activity and pharmacokinetic study of two synthesized benzoyl benzodioxol derivatives, compound I (methyl 2-(6-(2-bromobenzoyl)benzo[d][1,3]dioxol-5-yl)acetate), and compound II, 2-(6-benzoylbenzo[d][1,3]dioxol-5-yl)acetic acid, which showed very strong α-amylase inhibiting activity in our previous study. Then, diabetes was induced by the injection of streptozotocin to mice. The molecular docking simulations and analyses of density functional theory analyses were conducted to study the binding interactions with human pancreatic alpha-amylase, and their pharmacokinetic properties were further evaluated by ADMET profiling. Compound I showed the most important hypoglycemic effect, decreasing the blood glucose by 32.4%, higher than that of compound II by 14.8% and even the positive control acarbose by 22.9%. Histopathological examination revealed that diabetic livers showed portal inflammation with some apoptotic hepatocytes due to streptozotocin treatment, whereas controls without any treatment maintained normal liver architecture. Molecular docking studies gave results for the best binding affinity of the compound I, through its strong water bridges and π-π interactions, and also through analysis with density functional theory, was more stable and reactive when compared to compound II. Further ADMET analysis showed that both compounds shared a promising pharmacokinetic profile, and compound I had the potential for CNS penetration. Thus, compound I was selected as the best candidate for developing new hypoglycemic agents with potent efficacy, good binding interactions, and excellent pharmacokinetic properties.

The effects of four initial culture pH values (3, 4, 5, and 6) and nitrogen limitation on growth, TAG accumulation, lipid production, fatty acid profile, and estimated biodiesel quality of Starmerella magnoliae X3 were investigated. TAG and lipid levels were measured by Nile Red fluorescence and sulfo-phospho-vanilin (SPV) techniques, respectively. The results showed that a combination of nitrogen limitation and acidic pH significantly (p < 0.05) increased TAG accumulation, total lipid contents, and lipid productivity in Starmerella magnoliae X3 compared to the control group. Under nitrogen limitation, the highest TAG accumulation was achieved at initial pHs of 3 and 5 after 72 h of cultivation, and the highest lipid productivity (0.306 g L^-1 d^-1) was observed after 48 h at pH 3; the major fatty acids at the four pH values were oleic acid (63.6%-64%), palmitoleic acid (11.3%-12.5%), stearic acid (9.7%-11.4%), and palmitic acid (9.4%-10%). In addition, both stresses were associated with lower iodine value and higher cetane number of the biodiesel compared to the control. These findings suggest that cultivation in a low-nitrogen medium at an initial pH of 3 or 5 holds promise in increasing TAG production in Starmerella magnoliae X3.