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Zymoseptoria tritici is the causal agent of Septoria tritici blotch (STB), one of the most economically destructive wheat foliar diseases. In this study, we explore the physiological and molecular changes elicited in two wheat cultivars with divergent responses (Taichung 29 = susceptible, and Shafir = resistant) upon infection by Z. tritici. Our aim is to uncover novel insights into the intricate mechanisms that govern wheat defense against Z. tritici infection. Our quantitative histopathological study showed that H2O2 accumulated in the resistant cultivar to a higher degree compared to the susceptible cultivar at the biotrophic and switching phase. Additionally, we combined qPCR with a targeted quantitative HPLC technique to evaluate the expression profiles of 13 defense-related genes and profile the polyphenolic compounds induced differentially in the STB susceptible and resistant cultivar. Our finding indicated that five out of 13 genes were strongly up-regulated in the resistant cultivar compared with that of the susceptible one at eight days post-inoculation (dpi), corresponding to the transition phase present in the infection process of Z. tritici. Finally, our targeted HPLC analysis demonstrated that the traced phenolic compounds were highly elevated in the susceptible cultivar infected by Z. tritici compared with that of the resistant cultivar. In conclusion, our comprehensive analysis unveils a robust defense response in the resistant wheat cultivar Shafir, characterized by heightened H2O2 accumulation, significant up-regulation of key defense-related genes during the transition phase, and a distinct profile of polyphenolic compounds, shedding light on the intricate mechanisms contributing to its resistance against Z. tritici, thereby providing valuable insights for the development of more resilient wheat varieties. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1), the most potent toxic and carcinogenic secondary fungal metabolite, has frequently been reported in food/feed. Nowadays, herbal extracts are considered safe dietary additives to reduce the toxicity of such compounds. The protective capability of various combinations of hydro‐alcoholic extracts (HAEs) of ginger, turmeric, and Shirazi thyme, against the toxicity of AFB1 on the RAW264.7 cell line was investigated. The RAW264.7 cells were exposed to six different concentrations of AFB1 (0.09, 0.18, 0.37, 0.75, 1.5, and 3 μg mL−1) for 48 h to determine the IC50 of AFB1. AFB1 was estimated to have an IC50 of 1.5 μg mL−1 for RAW264.7 cells. Then, the cells were simultaneously incubated with 1.5 μg mL−1 AFB1 and the HAEs for 24 h. The HAEs significantly reduced the toxicity of AFB1 in RAW264.7 cells. HAE of Shirazi thyme showed the highest amount of total phenol content (TPC) and the highest DPPH• activity. In addition, a combination of ginger, turmeric, and Shirazi thyme extract showed the highest antioxidant activity. Rutin, quercetin, and apigenin were the main phenolic components of ginger HAE. A significantly positive correlation was observed between TPC of hydro‐alcoholic extract with ferric reducing antioxidant power (FRAP) and 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) values. Consequently, the simultaneous consumption of such extracts is recommended to protect the cells against dietary toxins. [ABSTRACT FROM AUTHOR]

Aims To identify promising fungal endophytes that are able to produce glycyrrhizin and enhance it in licorice and the mechanisms involved. Methods and results Fifteen fungal endophytes were isolated from Glycyrrhiza glabra L. rhizomes among which SGGF14 and SGGF21 isolates were found to produce glycyrrhizin by 4.29 and 2.58 µg g−1 dry weight in the first generation of their culture. These isolates were identified as Fusarium solani and Alternaria tenuissima , respectively, based on morphological characteristics and sequence analysis of internal transcribed spacer, TEF1, ATPase , and CAL regions. Subsequently, G. glabra plants were inoculated with these fungal isolates to examine their effect on glycyrrhizin production, plant growth parameters and the expression of key genes involved in glycyrrhizin pathway: SQS1, SQS2, bAS, CAS, LUS, CYP88D6 , and CYP72A154. Endophytes were able to enhance glycyrrhizin content by 133%–171% in the plants. Natural control (NC) plants, harboring all natural endophytes, had better growth compared to SGGF14- and SGGF21-inoculated and endophyte-free (EF) plants. Expression of SQS1, SQS2, CYP88D6 , and CYP72A154 was upregulated by inoculation with endophytes. LUS and CAS were downregulated after endophyte inoculation. Expression of bAS was higher in SGGF21-inoculated plants when compared with NC, EF, and SGGF14-inoculated plants. Conclusions Two selected fungal endophytes of G. glabra can produce glycyrrhizin and enhance glycyrrhizin content in planta by modulating the expression of key genes in glycyrrhizin biosynthetic pathway. [ABSTRACT FROM AUTHOR]

Glabridin is a well-known active isoflavone found in the root of licorice (Glycyrrhiza glabra L.) that possess a wide range of biological activity. Plant cells, hairy roots, and fungal endophytes cultures are the most important alternative methods for plant resources conservation and sustainable production of natural compounds, which has received much attention in recent decades. In the present study, an efficient culture condition was optimized for the biomass accumulation and glabridin production from fungal endophyte Aspergillus eucalypticola SBU-11AE isolated from licorice root. Type of culture medium, range of pH, and licorice root extract (as an elicitor) were tested. The results showed that the highest and lowest biomass production was observed on PCB medium (6.43 ± 0.32 g/l) and peptone malt (5.85 ± 0.11 g/l), respectively. The medium culture PCB was produced the highest level of glabridin (7.26 ± 0.44mg/l), while the lowest level (4.47 ± 0.02mg/l) was obtained from the medium peptone malt. The highest biomass (8.51 ± 0.43 g/l) and glabridin (8.30 ± 0.51mg/l) production were observed from the PCB medium adjusted with pH = 6, while the lowest value of both traits was obtained from the same medium with pH = 7. The highest production of total glabridin (10.85 ± 0.84mg/l) was also obtained from the culture medium treated with 100 mg/l of the plant root extract. This information can be interestingly used for the commercialization of glabridin production for further industrial applications. [ABSTRACT FROM AUTHOR]

This study offers new perspectives on the biochemical and physiological changes that occur in wheat following a gene-for-gene interaction with the fungal pathogen Zymoseptoria tritici. The Z. tritici isolate IPO323, carries AvrStb6, while ΔAvrStb6#33, lacks AvrStb6. The wheat cultivar (cv.) Shafir, bears the corresponding resistance gene Stb6. Inoculation of cv. Shafir with these isolates results in two contrasted phenotypes, offering a unique opportunity to study the immune response caused by the recognition of AvrStb6 by Stb6. We employed a variety of methodologies to dissect the physiological and biochemical events altered in cv. Shafir, as a result of the AvrStb6-Stb6 interaction. Comparative analysis of stomatal conductance demonstrated that AvrStb6-Stb6 mediates transient stomatal closures to restrict the penetration of Zymoseptoria tritici. Tracking photosynthetic functionality through chlorophyll fluorescence imaging analysis demonstrated that AvrStb6-Stb6 retains the functionality of photosynthesis apparatus by promoting Non-Photochemical Quenching (NPQ). Furthermore, the PlantCV image analysis tool was used to compare the H2O2 accumulation and incidence of cell death (2, 4, 8, 12, 16, and 21 dpi), over Z. tritici infection. Finally, our research shows that the AvrStb6-Stb6 interaction coordinates the expression and activity of antioxidant enzymes, both enzymatic and non- enzymatic, to counteract oxidative stress. In conclusion, the Stb6-AvrStb6 interaction in the Z. tritici-wheat pathosystem triggers transient stomatal closure and maintains photosynthesis while regulating oxidative stress. [ABSTRACT FROM AUTHOR]

The experiment was carried out to investigate the effect of aluminum silicate (AS), humic acid (HA), Saccharomyces cerevisiae cell wall (SC), herbal powder (HP) and a commercial toxin binder to alleviate the effects of aflatoxin B1 (AFB1) in broiler diet. In this experiment we used 320 day old chicks in a completely randomized design with 8 treatments and 4 replications, and 10 birds in each replicate, from 7 to 28 days of age. Experimental treatments were: 1) negative control (NC; without AFB1), 2) positive control (PC; contaminated by 0.3 mg AFB1 / kg diet), 3) PC + AS, 4) PC + AS + HA, 5) PC + AS + SC, 6) PC + AS + HA + SC, 7) PC + Magnotox as a commercial binder and 8) PC + HP. Feeding AFB1 contaminated diet reduced broiler performance, increased relative weights of liver, heart, pancreas and reduced serum albumin, total protein and glucose concentrations (P <0.05). Inclusion of AS in PC diet individually improved the negative effects of AFB1. However, supplementation of SC boosted AS effects, HA supplementation was rarely effective. Finally, it can be concluded that the combination of AS + SC has the highest adsorbing ability of AFB1. [ABSTRACT FROM AUTHOR]

BACKGROUND: The application of phytogenic additives in the form of essential oils have attracted considerable attention in poultry industry. OBJECTIVES: An experiment was conducted to evaluate effects of the blends of essential oils (EO) isolated from some medicinal plants including savory, thyme, fennel and rosemary on performance, blood metabolites, intestinal microflora, and meat quality of broilers. METHODS: Two hundred 1-day-old broilers were randomly allocated to 5 treatments with 4 replicates of 10 chicks. The dietary treatments included 1) NC (negative control; without EO), 2) PC (positive control; 300 mg commercial EO of oregano/kg diet), 3) SR (300 mg EOs of savory and rosemary/kg diet), 4) SRT (300 mg EOs of savory, rosemary and thyme/kg diet), 5) SRTF (300 mg EOs of savory, rosemary, thyme and fennel/kg diet). RESULTS: Neither PC nor combinations of EOs affected growth performance of broilers. Serum cholesterol reduced (P<0.05) by feeding the blend of EOs compared with NC. The lowest ileal Lactobacillus counts were observed in chicks fed diets supplemented with EO of oregano or SR (P<0.05). Dietary supplementation of oregano EO decreased (P<0.05) lipid peroxidation of thigh meat after 30 and 60 days of frozen storage compared with NC group. CONCLUSIONS: Broilers fed diets supplemented with EOs of oregano or SR had the lowest ileal Lactobacillus spp. counts probably due to their large amount of carvacrol contents which suppress growth and proliferation of Gram-positive bacteria. Contrary to blended EOs, oregano EO did not reduce serum cholesterol concentration, suggesting hypocholesterolemic effect of other compounds except carvacrol in EOs. The highest stability to meat oxidation was achieved in oregano EOs-fed broilers. This antioxidative effect was lower in treatments with less carvacrol contents. [ABSTRACT FROM AUTHOR]

The occurrence of antibiotic-resistant pathogenic bacteria is becoming a serious problem. The rise of multiresistance strains has forced the pharmaceutical industry to come up with new generation of more effective and potent antibiotics, therefore creating development of antivirulence compounds. Due to extensive usage of cell-to-cell bacterial communication (QS) systems to monitor the production of virulence factors, disruption of QS system results in creation of a promising strategy for the control of bacterial infection. Numerous natural quorum quenching (QQ) agents have been identified. In addition, many microorganisms are capable of producing smaller molecular QS inhibitors and/or macromolecular QQ enzymes. In present survey, anti QS activity of 1280 rhizosphere bacteria was assessed using the Pectobacterium carotovorum as AHLdonor and Chromobacterium violaceum CV026 as biosensor system. The results showed that 61 strains had highly AHL-degrading activity. Both Lux I and Lux R activity were affected by some isolates, suggesting that the rhizobacteria target both QS signal and receptor. These soil microorganisms with their anti-QS activity have the potential to be novel therapeutic agents for reducing virulence and pathogenicity of antibiotic resistant bacteria. [ABSTRACT FROM AUTHOR]

There is a great interest in the use of natural antifungal compounds for the control of fungi such as Rhizopus stolonifer in the postharvest agricultural system and food industry. In this study, the inhibitory effect of essential oil extracted from Satureja richingeri and its major compound, Carvacrol, on spore development and mycelial growth of R. stolonifer was investigated. Mycelium exhibited higher sensitivity to the oil and Carvacrol than that observed for spores. Spore treatment with oil and Carvacrol for 2 and 3 h led to a complete inhibition of spore germination, after 4 h of incubation. However, continuing the incubation to 6 h resulted in germination of 4.67% of the spores treated with the oil but no germination was detected for those treated with Carvacrol. It could be concluded that treatment with S. richingeri essential oil for 3 h would extend the shelf life of agricultural product considerably via inhibition of spore germination. [ABSTRACT FROM AUTHOR]

Aflatoxin B 1 (AFB 1 ), the most potent toxic and carcinogenic secondary fungal metabolite, has frequently been reported in food/feed. Nowadays, herbal extracts are considered safe dietary additives to reduce the toxicity of such compounds. The protective capability of various combinations of hydro-alcoholic extracts (HAEs) of ginger, turmeric, and Shirazi thyme, against the toxicity of AFB 1 on the RAW264.7 cell line was investigated. The RAW264.7 cells were exposed to six different concentrations of AFB 1 (0.09, 0.18, 0.37, 0.75, 1.5, and 3 μg mL -1 ) for 48 h to determine the IC 50 of AFB 1 . AFB 1 was estimated to have an IC 50 of 1.5 μg mL -1 for RAW264.7 cells. Then, the cells were simultaneously incubated with 1.5 μg mL -1 AFB 1 and the HAEs for 24 h. The HAEs significantly reduced the toxicity of AFB 1 in RAW264.7 cells. HAE of Shirazi thyme showed the highest amount of total phenol content (TPC) and the highest DPPH• activity. In addition, a combination of ginger, turmeric, and Shirazi thyme extract showed the highest antioxidant activity. Rutin, quercetin, and apigenin were the main phenolic components of ginger HAE. A significantly positive correlation was observed between TPC of hydro-alcoholic extract with ferric reducing antioxidant power (FRAP) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) values. Consequently, the simultaneous consumption of such extracts is recommended to protect the cells against dietary toxins., Competing Interests: Authors declare that they do not have any conflicts of interest., (© 2024 The Author(s). Food Science & Nutrition published by Wiley Periodicals LLC.)