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microbeMASST, a taxonomically informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbe-derived metabolites and relative producers without a priori knowledge will vastly enhance the understanding of microorganisms' role in ecology and human health.

Integrating grain yield, component traits and metabolite profiles aids in selecting drought‐adapted and climate‐smart crop varieties preferred by end users. Understanding the trends and magnitude of grain‐based metabolites is vital for selecting wheat genotypes with higher grain yield, drought tolerance, water use efficiency and product profiles. The aim of this study was to determine the response of newly developed wheat genotypes for grain yield and component traits and metabolites under drought stress to guide selection. One hundred wheat genotypes were preliminarily evaluated for agro‐morphological traits and water use efficiency under drought‐stressed and non‐stressed conditions during the 2022 and 2023 growing seasons using a 5 × 20 alpha lattice design with two replications. Ten high‐yielding genotypes were selected based on grain yield and were validated for agronomic traits and water use efficiency (WUE), and grain samples were assayed to profile their key metabolites under drought‐stressed conditions. Significant differences existed (p < 0.05) among the tested wheat genotypes for yield and yield components, WUE, drought tolerance and major metabolites to discern trait associations. The grain yield of the 10 genotypes ranged from 590.00 g m−2 (genotype LM70 × BW140) to 800.00 g m−2 (BW141 × LM71) under drought‐stressed treatment, whilst under non‐stressed it ranged from 760.06 g m −2 (LM70 × BW140) to 908.33 g m−2 (LM71 × BW162). Grain yield‐based water use efficiency of the assessed genotypes was higher under non‐stressed (0.18 g mm−1) than drought‐stressed (0.17 g mm−1) conditions. The highest drought tolerance index (211.67) and stress susceptibility index (0.77) were recorded for BW162 × LM71, whilst the lowest tolerance index (23.33) and stress susceptibility index (0.09) were recorded in BW141 × LM71. Grain metabolites, including the apigenin‐8‐C‐glucoside (log2Fold = 3.00) and malate (log2Fold = 3.60) were present in higher proportions in the high‐yielding genotypes (BW141 × LM71 and LM71 × BW162) under drought‐stressed conditions, whilst fructose (log2Fold = −0.50) and cellulose (log2Fold = −3.90) showed marked decline in the two genotypes. Based on phenotypic and metabolite profile analyses, genotypes BW141 × LM71 and LM71 × BW162 were selected for being drought‐tolerant, water‐use efficient and recommended for production or breeding. The findings revealed associations between yield components, water use efficiency and grain metabolites to guide the selection of best‐performing and drought‐tolerant wheat varieties. [ABSTRACT FROM AUTHOR]

Herein, a micro‐solid‐phase extraction (μSPE) method was developed using a pipette tip for rutin extraction, employing activated hollow carbon nanospheres (HCNSs) as the sorbent. Characterization of the activated carbon nanospheres through TGA, FTIR, and SEM analysis confirmed the success of the activation process. The study demonstrated the efficacy of PT‐μSPE in rutin extraction under pH 2 conditions with a standard concentration of 2 mg·L−1. The optimal mass of HCNSs was found to be 2 mg, and a loading volume of 500 μL resulted in the maximum recovery of rutin. Propan‐2‐ol was the best elution solvent with 15 aspirating/dispensing cycles. The correlation of determination (R2) for the calibration curve was found to be 0.9991, and the LOD and LOQ values were 0.604 and 1.830 mg·L−1, respectively. The applicability of the method was demonstrated by extracting rutin from a complex Moringa oleifera leaf extract with the relative standard deviation (RSD) of 3.26%, thereby validating this method as feasible for the extraction of useful bioactive compounds from complex plant samples. [ABSTRACT FROM AUTHOR]

Introduction: The presence of pharmaceuticals and personal care products in environmental matrices is considered one of the major scientific concerns. Most of these substances are disposed of unchanged through wastewater treatment plants and sewage systems. Consequently, they are continuously introduced into the water systems and progressively contaminate surface, ground and drinking water. During the COVID-19 pandemic, a large number of emerging contaminants including parabens were released to the environment through various routes. In this study, the occurrence of parabens (methylparaben (MePB), ethylparaben (EtPB), propylparaben (PrPB), and butylparaben (BuPB) was investigated in wastewater samples from various wastewater treatment plants (WWTPs) and the receiving surface waters in KwaZulu Natal and Gauteng Provinces (South Africa). Methods: The samples were collected between October 2020 and December 2021, covering the 2nd, 3rd and 4th waves of the COVID-19 pandemic. A solid phase extraction protocol with high-performance liquid chromatography was used to extract and enrich parabens before analysis. Results and Discussion: Methylparaben (2.02-84.7 μg/L), EtPB (<0.24-24.8 μg/L), PrPB (<0.26-55.1 μg/L), and BuPB (<0.27-17.3 μg/L) were quantified in wastewater influent collected WWTPs of KwaZulu Natal Province. While <0.19-5.43 μg/L, <0.16-5.63 μg/L, <0.17-6.89 μg/L, and <0.19-5.32 μg/L for MePB, EtPB, PrPB, and BuPB, respectively, were quantified in effluent wastewater from the same province. The concentrations of MePB, EtPB, PrPB, and BuPB in influent wastewater from Gauteng Province were 2.58-123 μg/L, <0.24-33.6 μg/L, 3.77-73.4 μg/L and <0.27-85.8 μg/L, respectively. In effluent wastewater, concentrations ranging from 0.24-17.76 μg/L (MePB), <0.16-4.88 μg/L (EtPB), 0.69-12.5 μg/L (PrPB), and <0.19-4.726 μg/L (BuPB) were quantified. During the 4th wave, the concentrations of parabens in surface water were lower compared to the second and third waves of the pandemic. In general, the paraben residues in the surface of KwaZulu Natal Province (<0.08-16.4 μg/L) were higher than those in Gauteng Province (0.08-3.14 µg/L). Methylparaben and propylparaben were dominant in all investigated samples (wastewater and surface water), followed by ethylparaben. The ecotoxicological risk assessment was carried out for aquatic biota, which was estimated in terms of risk quotients (RQs). RQs for the target compounds in river water indicated that MePB and EtPB pose low risk, whereas PrPB and BuPB pose low to medium risk to aquatic organisms. [ABSTRACT FROM AUTHOR]

Due to the emergence of drug-resistant microorganisms, the search for broad-spectrum antimicrobial compounds has become extremely crucial. Natural sources like plants and soils have been explored for diverse metabolites with antimicrobial properties. This study aimed to identify microorganisms from agricultural soils exhibiting antimicrobial effects against known human pathogens, and to highlight the chemical space of the responsible compounds through the computational metabolomics-based bioprospecting approach. Herein, bacteria were extracted from soil samples and their antimicrobial potential was measured via the agar well diffusion method. Methanolic extracts from the active bacteria were analyzed using the liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) technique, and the subsequent data was further analyzed through molecular networking approach which aided in identification of potential anti-microbial compounds. Furthermore, 16S rRNA gene sequencing enabled identification of the active bacterial isolates, where isolate 1 and 2 were identified as strains of Bacillus pumilus, whilst isolate 3 was found to be Bacillus subtilis. Interestingly, isolate 3 (Bacillus subtilis) displayed wide-ranging antimicrobial activity against the tested human pathogens. Molecular networking revealed the presence of Diketopiperazine compounds such as cyclo (D-Pro-D-Leu), cyclo (L-Tyr-L-Pro), cyclo (L-Pro-D-Phe), and cyclo (L-Pro-L-Val), alongside Surfactin C, Surfactin B, Pumilacidin E, and Isarrin D in the Bacillus strains as the main anti-microbial compounds. The application of the molecular networking approach represents an innovation in the field of bio-guided bioprospection of microorganisms and has proved to be an effective and feasible towards unearthing potent antimicrobial compounds. Additionally, the (computational metabolomics-based) approach accelerates the discovery of bioactive compounds and isolation of strains which offer a promising avenue for discovering new clinical antimicrobials. Finally, soil microbial flora could serve an alternative source of anti-microbial compounds which can assist in the fight against emergence of multi-drug resistance bacterial pathogens. [ABSTRACT FROM AUTHOR]

The biomass Solanum mauritianum (S. mauritianum) is an invasive weed specie; however, it is a source of medicinally important metabolites, as reported in literature, such as solasonine and solamargine. The study was directed at the optimization of microwave and aqueous two-phase-based extraction techniques which involved microwave-assisted extraction (MAE), aqueous two-phase extraction followed by microwave-assisted extraction (ATPE + MAE), and the "one-pot" microwave-assisted aqueous two-phase extraction (MA-ATPE) for extraction of solasonine and solamargine from leaves of S. mauritianum which was evaluated. The microwave-assisted extraction of solasonine and solamargine yielded optimums at 5.00 min, microwave power of 270 W, and solid/liquid of 0.1 g L−1 at an ethanol concentration of 60%. Application of a two-stage extraction (MAE + ATPE) in CaO-dried alcohol resulted in decreased amounts of solasonine and solamargine extracted. The best yields of solasonine and solamargine were achieved in the MA-ATPE method. Extraction of solamargine and solasonine using Na2CO3 in CaO-dried ethanol during MA-ATPE was approximately threefold and twofold greater than that of MAE + ATPE, respectively. Furthermore, extraction of solamargine and solasonine using NaCl in CaO-dried ethanol during MA-ATPE was approximately twofold greater than that of MAE + ATPE. The synergy of microwaves and salting-out in the "one-pot" MA-ATPE technique was shown to be a contributing factor for enhanced extraction of solamargine and solasonine from leaves of S. mauritianum. Application of this time- and energy-efficient extraction method could potentially be expanded for enrichment of medicinally important compounds from biomass of other medicinal plants. [ABSTRACT FROM AUTHOR]

Rationale: Although mass spectrometry (MS) is a powerful tool in structural elucidation of unknown flavonoids based on their unique fragmentation patterns, proposing the correct fragmentation mechanism is still a challenge from tandem mass spectrometry data only. In recent years, computational tools such as molecular networking and MS2LDA have played a major role in the identification of structurally related compounds through an in‐depth survey of their fragmentation patterns. Methods: Therefore, in this study, three viscutin molecules in Viscum combreticola Engl. crude extracts were characterised using ultra‐high‐performance liquid chromatography‐quadrupole‐time‐of‐flight tandem mass spectrometry and MS2LDA, a computational tool. Ion‐trap mass spectrometry and density functional theoretical modelling were used as confirmatory tools to rationalise the unique fragmentation patterns observed for these molecules. Results: Here, MS2LDA revealed the presence of a unique Mass2Motif in all the three viscutin molecules at m/z 137, which was confirmed to be a 1,3A− RDA (retro‐Diels‐Alder) fragmentation product using liquid chromatography‐ion‐trap mass spectrometry and density functional theoretical modelling. Moreover, MS2LDA proved to be useful in differentiating this spectral feature that was specific to viscutin molecules in the presence of other isobaric ions at m/z 137 occurring in compounds in other molecular families. Conclusion: Therefore, the results of the current study showed that computational tools such as MS2LDA are essential in uncovering some gas‐phase fragmentation reactions of molecules in MS and that theoretical modelling is a powerful tool in rationalising these reactions in metabolite identification. [ABSTRACT FROM AUTHOR]

This article, titled "Editorial: Plant growth-promoting and associated microbes: multi-, meta-omics, and applications," discusses the use of multiomics and metaomics techniques to study the functions of endophytes in plant growth and development. It highlights the potential applications of endophytes in various sectors, such as agriculture, medicine, and drug discovery. The article includes research on the role of halotolerant bacterial endophytes in mitigating salinity stress, the production of secondary metabolites by bacterial and fungal endophytes with potential applications in plant growth and protection as well as the treatment of HIV and multidrug-resistant fungi, and the role of the Beauveria bassiana endophyte in enhancing plant growth and resistance to pathogens. The article emphasizes the importance of understanding plant-endophyte interactions for developing sustainable agricultural practices and harnessing the potential of plant-associated microbiota to enhance crop productivity. [Extracted from the article]

Extraction is a vital prerequisite in most scientific studies involving the isolation and analysis of compounds from biological/environmental systems. The use of large quantities of organic solvents in performing both conventional and modern methods of extraction of these substances stirs issues of safety, environmental concern and cost-effectiveness. Subcritical water extraction (SWE) offers a suitable, safe, cost-effective and environmentally safe alternative compared to other methods as it takes advantage of the special properties of supercritical water under high temperature and pressure conditions (100–374 °C, >50 bar) to extract non-polar analytes. This review presents a critical appraisal of the principles and dynamics of SWE, and the current applications as a viable tool in the extraction of compounds from various biological matrices. Although more research is needed to improve full SWE applications, its adoption in the extraction of phytochemicals as well as other bioactive molecules including mycotoxins from both plant and animal components seems promising and needs to be properly exploited. [ABSTRACT FROM AUTHOR]