Endophytic fungi produce biologically robust metabolites suitable for diverse applications, which support the increasing exploration of these fungi. The study aimed to investigate the in vitro antimicrobial properties of the metabolites of endophytic fungus Aspergillus terreus which isolated from the leaves of Psidium guajava plants while the acute oral toxicity was assessed in vivo.
A. terreus (OR125572) was successfully isolated for the first time from P. guajava. The ethyl acetate extract of A. terreus exhibited antibactericidal effects against Enterobacter aerogenes with a minimum inhibitory concentration of 18.75 mg/ml in contrast to 75.00 ± 0.0, 37.50, and 37.50 mg/ml, respectively against Staphylococcus aureus, Escherichia coli, and Bacillus sphaericus were 75.00 ± 0.0, 37.50, and 37.50 mg/ml, respectively. Analysis of the crude extract obtained from A. terreus by GC-MS revealed a total of 32 distinct compounds. The major components included 1,2-benzenedicarboxylic acid, di-iso-octyl ester; hexyl oxecan-2-one and phenol. The acute oral toxicity study found no symptoms of toxicity and no mortality until the 14th d, suggesting that the LD50 value of A. terreus extract might exceed 1 ml/kg. The group receiving 0.5 ml/kg of A. terreus extract experienced a 42.9% increase in body weight, while administration of varying dosages resulted in a significant reduction in MCV levels. There was also a significant increase in the proportion of monocytes across all treated groups.
The study demonstrated the potential of A. terreus as a source of antimicrobial and other bioactive compounds, with relatively low acute toxicity.
How to cite: Shehabeldine AM, Abdelaziz AM, Abdel-Maksoud MA, et al. Antimicrobial characteristics of endophytic Aspergillus terreus and acute oral toxicity analysis. Electron J Biotechnol 2024;72. https://doi.org/10.1016/j.ejbt.2024.07.003.
Soil salinization is one of the key factors restricting the production of cropland. Once rice is subjected to alkali stress at the bud burst stage, the yield will suffer irreparable serious loss. Compared with salt tolerance, studies on QTL mapping and candidate gene analysis of rice alkali tolerance are limited.
In this study, we used the F2:3 population derived from the alkali-tolerant cultivar LD21 and the alkali-sensitive cultivar WL138 to construct an alkali-tolerant DNA mixing pool, and the BSA (Bulked Segregation Analysis) method was used for re-sequencing. The main QTL qRSLB9 controlling the relative shoot length of rice under alkali stress was mapped by QTL-seq. The candidate interval was narrowed to 346.5 kb by regional linkage mapping, which containing 6 DEGs screened through transcriptome sequencing. The qRT-PCR and candidate gene sequencing showed that LOC_Os09g24260 was most likely to control relative shoot length (RSL) in rice as a major gene who encodes the WD domain, G-beta repeat domain-containing protein.
Based on these results, LOC_Os09g24260 was the candidate gene of qRSLB9 conferring alkalinity tolerance to rice at the bud burst stage. Our study provides valuable genetic information and materials for breeding new rice varieties with alkalinity tolerance.
How to cite: Wang J, Bian J, Liu L, et al. Screening and analysis of candidate genes conferring alkalinity tolerance in rice (Oryza sativa L.) at the bud burst stage based on QTL-seq and RNA-seq. Electron J Biotechnol 2024;71. https://doi.org/10.1016/j.ejbt.2024.07.002.
Different methods for the extraction of trypsin inhibitors in beans (Phaseolus spp.) were investigated. Two randomised complete laboratory experiments were performed, one on the seeds and one on the pods. In the first, the seeds of common bean variety KIS Marcelijan, breeding line Ref_316 × 498 and runner bean variety Bonela were examined. In the second, the fresh pods of five common beans (three breeding lines, two varieties) were analysed. Four extraction methods were used, including ultrasonic-assisted extraction (UAE) for 15 and 30 min and shaking-assisted extraction for 60 and 180 min.
The results showed a significant increase in trypsin inhibitor activity-related traits in UAE compared to shaking extraction, with the 15 min ultrasonic process showing better efficacy than the one with 30 min duration. In the seed experiment, the breeding line Ref_316 × 498 showed the highest Trypsin Units Inhibited (TUI) and TUI/mg sample after a 15 min UAE. In the pod experiment, the breeding line 228_4aa_ca also showed the highest TUI and TUI/mg sample after a 15 min extraction with UAE. These results underline the potential of UAE to maximise trypsin inhibitor content. In addition, remarkable correlations between TUI, TUI/mg sample and the percentage of trypsin inhibition (%TIn) were observed in both experiments.
These results provide valuable insights into the relationship between bean genetic resources, extraction methods and trypsin inhibitor content in bean pods and seeds and serve as a basis for refining extraction protocols. The study encourages further research on the practical implications of investigated protocols for breeding programmes and agricultural practices.
How to cite: Tavakoli Hasanaklou H, Pipan B, Meglič V, et al. Trypsin inhibitors in seeds and pods of Phaseolus vulgaris/coccineus: A comparative study of shaking and ultrasonic extraction methods. Electron J Biotechnol 2024;71. https://doi.org/10.1016/j.ejbt.2024.05.003.
Using cell lines to explore the function of organic compounds is fundamental in biotechnology. Evaluating new additives intended to improve animal production is challenging due to the complexity and uncertainty of in vivo testing. This study investigated the action of a compound with antioxidant properties using cells from terrestrial (LMH cells line) and aquatic vertebrates (CHSE-214).
The results of our study provide reassuring evidence of the compound’s safety for use in animal production. The compound demonstrated no adverse effects on cell viability, indicating its potential for safe application. Furthermore, the compound’s antioxidant properties were evident, with a 100% recovery in both cell lines when exposed to hydrogen peroxide 0.1 mM. It also effectively reduced cellular ageing caused by metabolic processes, as measured by the TBARS formation in both cell lines, from 5 MDA µM/mg protein to 2.5 MDA µM/mg protein when used at 0.05 or 0.5 g/L. Notably, this action did not increase cell membrane oxidation, further supporting its safety profile.
These findings indicate that the compound has an antioxidant effect and can be used independently or in combination with metabolic stimulants in the diets of production animals. Applying this additive and its possible synergy with other compounds could help reduce oxidative stress and improve growth in animal production. The data generated in this study provide a solid basis for designing diets incorporating this additive to observe improvements in animal production based on activity observed at the cellular level.
How to cite: Olivares- Ferretti P, Maguregui E, Chavez V, et al. Novel antioxidant additive ENTAN molecule for animal production: Evaluation at the cellular level. Electron J Biotechnol 2024;71. https://doi.org/10.1016/j.ejbt.2024.07.001.
Lactobacillus plantarum can produce many secondary metabolites, some of which have antibacterial effects. This study aimed to explore the main antimicrobial metabolites of Lactobacillus plantarum LPZN19.
The results of antibacterial activity after fermentation for different durations showed that the metabolites from the LPZN19 cell-free supernatant (LCFS) after 24 h had the strongest antibacterial activity, which was confirmed by the highest contents of organic acids and fatty acids in the LCFS after 24 h. Lactic acid, phenyllactic acid, malic acid, aspartic acid, dodecanoic acid and propionic acid were the main differentially abundant metabolites. LCFS was separated by semi-preparative liquid chromatography to obtain 4 antibacterial parts, mainly organic acids such as lactic acid, glycolic acid, and citric acid, and fatty acids such as stearic acid, palmitic acid, and octanoic acid. In addition, fatty glycerides and amino acids with antimicrobial activity were included.
Our findings indicate that the main antimicrobial metabolites of L. plantarum LPZN19 include organic acids, fatty acids, fatty glycerides and some amino acids with antimicrobial activity, which not only clarifies the main antimicrobial metabolites of L. plantarum LPZN19 but also provides an effective method for rapid screening of antimicrobial substances.
How to cite: Wang Y, Xu Y. Analysis and identification of the main antimicrobial metabolites of Lactobacillus plantarum LPZN19. Electron J Biotechnol 2024;71. https://doi.org/10.1016/j.ejbt.2024.05.005.