Search

In an effort to find a potential antagonist for Cryptostroma corticale , the causal agent of the sooty bark disease, different fungi previously isolated from Acer pseudoplatanus were tested in dual culture antagonism assays with C. corticale. In total 102 fungal strains, mainly Ascomycota , were tested. Each potentially antagonistic strain was paired with three different strains of C. corticale. Four different tests were conducted to get a better understanding of the interactions between C. corticale and the potential antagonists. Test 1 was a dual culture set up at room temperature with all 102 strains to get an overview of the interactions with C. corticale , as well as placing the potential antagonist on a Petri dish 1 week prior to C. corticale for a selection of fungi. For Test 2, only fungi which showed inhibition at distance in Test 1 were chosen and tested on different media at 25°C, the optimal growing temperature of the pathogen. In Test 3, fungi showing signs of antagonism in Test 1 were tested against C. corticale in a 6:1 ratio of potential antagonist plugs to the C. corticale plug. For Test 4, the viability of C. corticale hyphae was tested after they stopped growing in dual culture with a potential antagonist. These in vitro trials show that C. corticale displays a very competitive behavior, overgrowing most of the tested fungi. However, nine of the tested fungal strains, showed an antagonism at distance for at least one of the C. corticale strains. Over all tests, Hypholoma fasciculare , Jackrogersella cohaerens , Paracamarosporium cf. fagi , Pezicula sporulosa, and Preussia cf. aemulans showed the highest potential in regard of functionality as a biological control agent. [ABSTRACT FROM AUTHOR]

Endophytic fungi associated with selected aquatic plants, Eichhornia crassipes, Nymphaea nouchali, Salvinia minima and S. molesta were evaluated. Ectophoma salviniae sp. nov. and Neottiosporina mihintaleensis sp. nov. are introduced as novel taxa from Salvinia spp. from Sri Lanka. Chaetomella raphigera is reported as a new geographical record, Colletotrichum siamense and C. truncatum are reported as novel host records in aquatic plants, while Phyllosticta capitalensis has been identified on the same host (Nymphaea nouchali) in the North-Central Province of Sri Lanka. Identification of the fungi was based on morphological characteristics and multi-locus phylogenetic analyses using ITS, LSU, SSU, ACT , CHS- 1, GAPDH , tub 2, rpb 2, and tef 1-α molecular markers. The identified fungi were analysed for extracellular enzymatic properties. According to the qualitative analysis, Ectophoma salviniae sp. nov. exhibited the highest amylase production, Chaetomella raphigera exhibited the highest cellulase enzyme production, and Neottiosporina mihintaleensis sp. nov. exhibited the highest laccase production. The results demonstrate the aquatic fungal diversity in this region and their extracellular enzymatic potentials, providing valuable insights for future biotechnological approaches. [ABSTRACT FROM AUTHOR]

Symbiotic associations play a role in plant ecology and evolution, but the outcome of the interaction depends on the life‐history traits of the partners and the environmental context. Although symbiosis with vertically transmitted microorganisms should result in mutualism, it is not clear how the transmission process aligns with the outcome of the context‐dependent symbiosis.For 3 years, we sampled individuals of an annual plant species that forms symbiosis with a vertically transmitted fungal endophyte, in paired stands of two contrasting vegetation communities (humid mesophytic meadows [HMM]: productive/low stress, and humid prairies [HP]: less productive/high stress). We estimated the prevalence of symbiosis at the population level, and the fitness of the plant, the symbiotic status and vertical transmission efficiency at the individual level.Over 3 years, the prevalence of symbiosis was ≈100% in HMM and ≈75% in HP. Plant fitness was very low and high in years with precipitation below and above the yearly mean, respectively. The higher fitness of endophyte‐symbiotic plants was evident in the HMM and high precipitation years. Vertical transmission of endophytes was higher in HMM (≈96%) compared to HP (≈93%) and was not related to plant fitness. Despite transmission inefficiencies in HP, changes in prevalence within the growing season (from seeds to the final plant stand) suggest a fitness advantage for symbiotic plants.Vertical transmission is expected to promote mutualism as it aligns partners' fitness. Although symbiotic plants showed higher fitness and the probability of transmission failures was higher among low‐fitness plants, the variation in transmission efficiency between plants and vegetation communities was not related to the fitness of the individual host. Our study provides evidence that context‐dependent vertical transmission efficiency and endophyte‐mediated fitness advantages interact complexly to determine the prevalence of symbiosis in populations that occur in contrasting vegetation communities. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Abstract Background Thymus vulgaris is a valuable medicinal plant widely cultivated for its aromatic and medicinal properties. However, like many plants, T. vulgaris faces challenges such as drought stress, which significantly affects its growth, morphological, physiological, and biochemical processes. Understanding how endophytic fungi isolated from Lamiaceae family influence T. vulgaris under varying watering regimes can enhance its resilience against drought stress. This study aims to assess the impact of individual and co-inoculation of three native endophytic species, i.e., Fusarium sp. (F1), Cladosporium puyae (F2), and Curvularia australiensis (F3), on T. vulgaris growth parameters under different irrigation regimes in greenhouse conditions. Results It has been discovered that using fungal endophytes as a biological tool can benefits T. vulgaris under drought stress. The results indicated that drought stress significantly reduced the growth, chlorophyll, and carotenoid content of plants lacking endophytes. Combinatory applications with fungal endophytes significantly improved the above-mentioned parameters under drought stress. Lipid peroxidation levels were significantly reduced in plants inoculated with bacterial endophytes. Drought stress significantly increased the activities of ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione reductase (GR), peroxidase (POD), and catalase (CAT) in drought conditions. Conclusions The findings suggested that the addition of fungal endophytes to the inoculum enhances drought tolerance in T. vulgaris by mitigating the harmful impact of drought stress on plant growth and physiological functions. The higher activity of antioxidant enzymes and improved redox state of glutathione are responsible for plants’ greater resistance to drought.

Plant–microbe interactions play a pivotal role in shaping host fitness, especially concerning chemical defense mechanisms. In cycads, establishing direct correlations between specific endophytic microbes and the synthesis of highly toxic defensive phytochemicals has been challenging. Our research delves into the intricate relationship between plant–microbe associations and the variation of secondary metabolite production in two closely related Zamia species that grow in distinct habitats; terrestrial and epiphytic. Employing an integrated approach, we combined microbial metabarcoding, which characterize the leaf endophytic bacterial and fungal communities, with untargeted metabolomics to test if the relative abundances of specific microbial taxa in these two Zamia species were associated with different metabolome profiles. The two species studied shared approximately 90% of the metabolites spanning diverse biosynthetic pathways: alkaloids, amino acids, carbohydrates, fatty acids, polyketides, shikimates, phenylpropanoids, and terpenoids. Co-occurrence networks revealed positive associations among metabolites from different pathways, underscoring the complexity of their interactions. Our integrated analysis demonstrated to some degree that the intraspecific variation in metabolome profiles of the two host species was associated with the abundance of bacterial orders Acidobacteriales and Frankiales, as well as the fungal endophytes belonging to the orders Chaetothyriales, Glomerellales, Heliotiales, Hypocreales, and Sordariales. We further associate individual metabolic similarity with four specific fungal endophyte members of the core microbiota, but no specific bacterial taxa associations were identified. This study represents a pioneering investigation to characterize leaf endophytes and their association with metabolomes in tropical gymnosperms, laying the groundwork for deeper inquiries into this complex domain. [ABSTRACT FROM AUTHOR]

Endophytes, which are typically bacteria or fungi, are vital for sustainable agriculture by inhabiting both inter- and intracellular spaces within plants. Pathogens exert a significant impact on plants, leading to global annual crop losses. Due to their distinctive abilities, fungal and bacterial endophytes are essential in biocontrol, and the synthesis of bioactive compounds that effectively combat plant diseases. While pesticides and fungicides have the potential to control pathogen growth in plants and improve crop yield, their widespread use contributes to environmental pollution and poses various health risks to animals and humans. Consequently, there arises a necessity for alternative biocontrol agents, providing environmentally friendly methods to efficiently combat plant diseases. This review investigates the involvement of fungal and bacterial endophytes in addressing fungal and bacterial pathogens, delving into their biocontrol mechanisms. [ABSTRACT FROM AUTHOR]

Fungal endophytes, symbiotic microorganisms residing within plants, are renowned for producing bioactive secondary metabolites with diverse beneficial properties. We investigated the antimicrobial potential of fungal endophytes isolated from Solanum mauritianum, an invasive weed, against clinically significant bacterial pathogens. Selected fungal endophytes (Penicillium chrysogenum, Fusarium sp., and Paracamarosporium leucadendri) were isolated from the plant's leaves and fruits. Their crude extracts were tested against various referenced strains, such as Mycobacterium species (M. smegmatis ATCC 607 and M. bovis ATCC 27290), Staphylococcus aureus ATCC 6571, Bacillus subtilis ATCC 11774, Klebsiella species (K. pneumoniae ATCC 10031 and K. oxytoca ATCC 8724), Escherichia coli ATCC 10536, and Pseudomonas aeruginosa ATCC 10145, using the Kirby-Bauer disk diffusion method. Resazurin Microtiter Assay was used for the determination of the minimum inhibitory concentration. The chemical nature of the secondary metabolites in the crude extracts produced by fungal endophytes was evaluated using high-resolution liquid chromatography–mass spectrometry (LC-MS) using water and acetonitrile gradient. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS/MS) was employed for untargeted metabolomics. LC-QTOF-MS/MS identified 63 bioactive compounds across the three endophytes. P. chrysogenum had the highest activity against S. aureus and M. smegmatis (1.15 mg/mL and 0.02 mg/mL, respectively), while P. leucadendri demonstrated moderate activity against M. smegmatis (2.91 mg/mL) and E. coli (1.16 mg/mL). Fusarium sp. exhibited the broadest spectrum of antibacterial activity, with MIC values ranging from 0.03 mg/mL (B. subtilis) to 10 mg/mL (M. smegmatis). P. leucadendri produced 29 metabolites, Fusarium sp. had 23 identified metabolites, and a total of 11 metabolites were identified from P. chrysogenum. The fruits of the plant, accounting for 60%, appeared to be the most abundant in the endophyte diversity when compared to the stems and leaves. This study highlights the potential of fungal endophytes from S. mauritianum as a source of novel bioactive compounds, particularly against multidrug-resistant pathogens, contributing to the ongoing efforts to combat antimicrobial resistance. [ABSTRACT FROM AUTHOR]

The growing emergence of multi-drug resistant microbial strains has kept the scientific world searching for novel bioactive compounds with specific chemical characteristics. Accordingly, researchers have started exploring the understudied metabolites from endophytes as a new source of bioactive compounds. In this context, the current study was designed to evaluate the bioactive properties of endophytic fungi from the Mokrzański forest in Wrocław, Poland that have not yet been fully researched. Forty-three endophytic fungi were isolated from twelve distinct plants. Following their cultivation, fungal extracts were separately prepared from biomass and cell-free filtrates, and their antibacterial, antifungal (against human and plant pathogens), and antioxidant properties were examined. Five promising fungi after screening were identified to possess all of these activities. These strains and their respective plant hosts were Trichoderma harzianum BUK-T (Fagus sylvatica), Aspergillus ochraceus ROB-L1 (Robinia pseudoacacia), Chaetomium cochliodes KLON-L1, Fusarium tricinctum KLON-L2 (Acer platanoides), and Penicillium chrysogenum SOS-B2 (Pinus sylvestris). Moreover, gamma irradiation at several doses (Gy) was separately applied to the fungal cultures to study their effects on the recorded activities. Finally, compounds after preparative thin-layer chromatography fractionation of the five fungal strains were identified by GC-MS. These findings suggest that the isolated endophytic fungi could serve as novel sources of bioactive metabolites with antibacterial, antifungal, and antioxidant properties, potentially paving the way for future research and the development of new bioactive compounds. [ABSTRACT FROM AUTHOR]

Symbiotic organisms may contribute to a host plant's success or failure to grow, its ability to maintain viable populations, and potentially, its probability of establishment and spread outside its native range. Intercellular and intracellular microbial symbionts that are asymptomatic in their plant host during some or all of their life cycle – endophytes – can form mutualistic, commensal, or pathogenic relationships, and sometimes novel associations with alien plants. Fungal endophytes are likely the most common endosymbiont infecting plants, with life‐history, morphological, physiological, and plant‐symbiotic traits that are distinct from other endophytic guilds. Here, we review the community dynamics of fungal endophytes during the process of plant invasion, and how their functional role may shift during the different stages of invasion: transport, introduction (colonisation), establishment, and spread. Each invasion stage presents distinct ecological filters that an alien plant must overcome to advance to the subsequent stage of invasion. Endophytes can alternately aid the host in overcoming stage‐specific filters, or contribute to the barriers imposed by filters (e.g. biotic resistance), thereby affecting invasion pathways. A few fungi can be transported as seed endophytes from their native range and be vertically transmitted to future generations in the non‐native range, especially in graminoids. In other plant groups, alien plants mostly acquire endophytes via horizontal transmission from the invaded plant community, and the host endophyte community is shaped by host filtering and biogeographic factors (e.g. dispersal limitation, environmental filtering). Endophytes infecting alien plants (both those transported with their host and those accumulated in the non‐native range) may influence invasion success by affecting plant growth, reproduction, environmental tolerance, and pathogen and herbivory defences; however, the direction and magnitude of these effects can be contingent upon the host identity, life stage, ecological conditions, and invasion stage. This context dependence may cause endophytic fungi to shift to a non‐endophytic (e.g. pathogenic) functional life stage in the same or different hosts, which can modify alien–native plant community dynamics. We conclude by identifying paths in which alien hosts can exploit the context dependency of endophyte function in novel abiotic and biotic conditions and at the different stages of invasion. [ABSTRACT FROM AUTHOR]

Endophytic fungi inhabit various plant tissues and organs without inducing evident disease symptoms. They can contribute positively to the growth of plants, bolster plants resilience to environmental and biological stresses, and facilitate the accumulation of secondary metabolites. These microbial resources possess significant developmental and utilization value in various applications. Hence, this study focused on exploring the plant growth-promoting (PGP) traits of 14 endophytic fungi from Ligusticum chuanxiong Hort (CX) and elucidating the effects and mechanisms that facilitate plant growth. According to PGP activity evaluation, the majority of strains demonstrated the capacity to produce IAA (78.57%), siderophores (50.00%), ammonia (35.71%), potassium solubilization (21.43%), nitrogen fixation (57.14%), and phosphate solubilization (42.86%). Further investigations indicated that the levels of IAA ranged from 13.05 to 301.43 μg/mL, whereas the soluble phosphorus levels ranged from 47.32 to 125.95 μg/mL. In cocultivation assays, it was indicated that Fusarium sp. YMY5, Colletotrichum sp. YMY6, Alternaria sp. ZZ10 and Fusarium sp. ZZ13 had a certain promoting effect on lateral root number and fresh weight of tobacco. Furthermore, ZZ10 and ZZ13 significantly enhanced the germination potential, germination index, and vigor index of tobacco seeds. The subsequent potted trials demonstrated that the four endophytic fungi exhibited an enhancement to growth parameters of tobacco to a certain extent. ZZ10 and ZZ13 treatment had the best promotion effect. Inoculation with YMY5 increased the chlorophyll a and total chlorophyll content. ZZ10 and ZZ13 treatment remarkably increased the net photosynthetic rate, soluble sugars and soluble protein content, catalase and peroxidase activities, and lowered malondialdehyde content in tobacco leaves. In addition, YMY5 remarkably elevated superoxide dismutase activities. ZZ13 upregulated the expression of growth-related gene. Among them, ZZ13 had a better growth-promoting effect. In conclusion, these endophytic fungi possessing multi-trait characteristics and the capacity to enhance plant growth exhibit promising potential as biofertilizers or plant growth regulators. [ABSTRACT FROM AUTHOR]

Plants and microbes have co-evolved in nature over the past few years for their better adaptation. This intricate symbiotic relationship is captured in the hologenome concept, which emphasizes that the combined genome of plants and their associated microbial partners, function as a single evolutionary unit. It highlights the possibility of using beneficial microorganisms, including fungal endophytes, to increase plant growth and productivity by habitat-adapted symbiosis mechanism. According to earlier research, fungal endophytes activate specific physiological traits in crops. However, the specific ways in which these endophytes benefit plants and underlying mechanisms remain unclear. In this context, the objective of this study was to utilize the model system Arabidopsis thaliana to explore possible mechanisms of plant-endophyte interaction. Eight fungal endophytes (K-23, LAS-6, N-14, P-10, P-37, PJ-9, SF-5 and V4-J) previously isolated from extreme habitats were re-examined in terms of their colony morphology. Based on the leads from previous studies, five fungal endophytes (LAS-6, N-14, P-10, PJ-9 and SF-5) were selected and exposed for in vitro co-cultivation with new host A. thaliana. The highest colonisation percentage was observed for the SF-5 (67%) followed by P-10 (33%), LAS-6 (27%) and N-14 (33%), whereas a lower colonisation percentage was observed for PJ-9 (20%). Additionally, these endophytes showed growth promotion activity by improved photosynthetic leaf area, root dry weight and shoot dry weight in fourteen days old Arabidopsis seedlings. The identification of trait-specific endophytes and incorporation of hologenome-enrichment approach can serve as a sustainable and eco-friendly strategy for crop improvement. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive overview of recent discoveries and advancements in the field of steroid chemistry, highlighting the isolation and characterization of various steroidal compounds from natural sources. This paper discusses a wide range of steroids, including pregnane steroids, steroidal alkaloids, ketosteroids, and novel triterpenoids, derived from marine organisms, fungi, and plants. Significant findings include the isolation of bioactive compounds such as the cytotoxic erectsterates from microorganisms, soft corals, the unusual tetracyclic steroid penicillitone from a fungal culture, and innovative steroidal derivatives with potential anti-inflammatory and anticancer activities. The synthesis of steroids from microorganisms as a tool for pharmaceutical development is also explored, showcasing the role of microbial biotransformation in generating steroidal drugs. Additionally, this paper emphasizes the ecological and medicinal relevance of these compounds, which are often used in traditional medicine and have potential therapeutic applications in treating diseases like cancer and microbial infections. This article serves as a vital resource for researchers interested in the chemical diversity of steroids and their applications in drug discovery and development. [ABSTRACT FROM AUTHOR]

Grasses hosting Epichloë endophytes are protected against herbivores due to the production of various fungal alkaloids. Previous research has found that high foliar phosphorus concentrations reduce the level of the alkaloid ergovaline, thereby reducing the endophyte‐mediated herbivore resistance. Yet, the impact of phosphorus on ergovaline biosynthesis versus its influence on endophyte growth and synthesis of other fungal alkaloids remains unresolved. Our objective was to elucidate these relationships.We grew endophyte‐symbiotic and non‐symbiotic Festuca arundinacea plants and fertilised them with different doses of phosphorus. Later, half of the plants from each treatment were challenged with larvae of the generalist chewing insect Spodoptera frugiperda. We assessed the relationships between foliar phosphorus levels, fungal mycelium and alkaloid concentrations, as well as their impacts on larvae performance, herbivore‐caused damage and plant biomass.Endophyte mycelial biomass in plant tissue was found to be independent of foliar phosphorus concentration. The alkaloids lolines and peramine showed a linear relationship with mycelial biomass but no correlation with foliar phosphorus. Surprisingly, high ergovaline concentrations were positively associated with an interaction between endophyte mycelial biomass and foliar phosphorus concentration. Although herbivory increased loline concentration, only high concentrations of ergovaline and peramine were related to reduced S. frugiperda larvae weight gain. However, endophyte presence did not reduce herbivory damage on plants.Contrary to expectation, we did not find a negative but a positive association between concentrations of foliar phosphorus and ergovaline alkaloid, through its interaction with endophyte mycelial biomass. Alternatively, our findings suggest that phosphorus plays a crucial role in modulating the Epichloë‐mediated defensive mutualism, primarily through its effects on ergovaline rather than on endophyte concentration or production of other alkaloids. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Our research group isolated an endophyte yeast from the endemic plant Echinopsis chiloensis. This yeast, identified as Naganishia sp, produces volatile organic compounds (VOC) with antifungal activity against Botrytis cinerea. Due to the need for alternative control methods for this pathogen, the effect of VOC on B. cinerea was analyzed. On the fourth day of cultivation, in the presence of VOCs, the mycelial growth of B. cinerea stopped. VOCs inhibited 32.8% of the conidia germination and reduced sporulation by 70.6%. These compounds promoted the formation of infection cushions. VOCs caused damage to the cell wall and plasma membrane in B. cinerea. On the other hand, the volatile compounds induced oxidative stress, and led to membrane lipid peroxidation after 16 and 24 h of incubation in the presence of VOCs, because an increased level of malondialdehyde content was observed. These compounds exerted a fungistatic effect on B. cinerea. The volatile compounds emitted by Naganishia sp were identified by gas chromatography coupled with mass spectrometry as 3-methylbutyl acetate, ethylbenzene, 1-ethyl-3-methylbenzene, 2-phenylethanol, 2-heptanone and (5E)-6,10-dimethylundeca-5,9-dien-2-one. The most abundant volatile compound, 2-phenylethanol, inhibited the mycelial growth of B. cinerea with an IC50 value of 0.21 µL mL−1. The effect of this pure compound was also fungistatic. Finally, it was shown that volatile compounds decreased the severity of B. cinerea infection in tomatoes and grapes by 64.7 and 43,1%, respectively. This is the first report identifying volatile compounds emitted by a Naganishia sp. and describing their mode of action against B. cinerea. [ABSTRACT FROM AUTHOR]

Endophytic fungi associated with selected aquatic plants, Eichhornia crassipes, Nymphaea nouchali, Salvinia minima and S. molesta were evaluated. Ectophoma salviniae sp. nov. and Neottiosporina mihintaleensis sp. nov. are introduced as novel taxa from Salvinia spp. from Sri Lanka. Chaetomella raphigera is reported as a new geographical record, Colletotrichum siamense and C. truncatum are reported as novel host records in aquatic plants, while Phyllosticta capitalensis has been identified on the same host (Nymphaea nouchali) in the North-Central Province of Sri Lanka. Identification of the fungi was based on morphological characteristics and multi-locus phylogenetic analyses using ITS, LSU, SSU, ACT, CHS-1, GAPDH, tub2, rpb2, and tef1-α molecular markers. The identified fungi were analysed for extracellular enzymatic properties. According to the qualitative analysis, Ectophoma salviniae sp. nov. exhibited the highest amylase production, Chaetomella raphigera exhibited the highest cellulase enzyme production, and Neottiosporina mihintaleensis sp. nov. exhibited the highest laccase production. The results demonstrate the aquatic fungal diversity in this region and their extracellular enzymatic potentials, providing valuable insights for future biotechnological approaches.

In an effort to find a potential antagonist for Cryptostroma corticale, the causal agent of the sooty bark disease, different fungi previously isolated from Acer pseudoplatanus were tested in dual culture antagonism assays with C. corticale. In total 102 fungal strains, mainly Ascomycota, were tested. Each potentially antagonistic strain was paired with three different strains of C. corticale. Four different tests were conducted to get a better understanding of the interactions between C. corticale and the potential antagonists. Test 1 was a dual culture set up at room temperature with all 102 strains to get an overview of the interactions with C. corticale, as well as placing the potential antagonist on a Petri dish 1 week prior to C. corticale for a selection of fungi. For Test 2, only fungi which showed inhibition at distance in Test 1 were chosen and tested on different media at 25°C, the optimal growing temperature of the pathogen. In Test 3, fungi showing signs of antagonism in Test 1 were tested against C. corticale in a 6:1 ratio of potential antagonist plugs to the C. corticale plug. For Test 4, the viability of C. corticale hyphae was tested after they stopped growing in dual culture with a potential antagonist. These in vitro trials show that C. corticale displays a very competitive behavior, overgrowing most of the tested fungi. However, nine of the tested fungal strains, showed an antagonism at distance for at least one of the C. corticale strains. Over all tests, Hypholoma fasciculare, Jackrogersella cohaerens, Paracamarosporium cf. fagi, Pezicula sporulosa, and Preussia cf. aemulans showed the highest potential in regard of functionality as a biological control agent.

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]

Non-insecticidal control strategies using entomopathogens, nematodes, and endophytes provide sustainable and safer alternatives for managing crop pests. This study investigated the potential of different fungal endophytes, specifically Beauveria bassiana strains, in colonizing cotton plants and their efficacy against tarnished plant bug, Lygus lineolaris. The effect of endophytes on plant growth parameters and cotton yield were measured during different plant growth stages. The entomopathogenicity of these fungi was studied in diet cup bioassays using L. lineolaris adults. The behavior of adult males and females toward endophytic cotton squares was analyzed using olfactometer assays. The experiments showed that the fungal endophytes colonized the plant structures of cotton plants, which resulted in an increase in the number of cotton squares, plant height, and weight compared to control plants. B. bassiana strains/isolates such as GHA, NI-8, and JG-1 caused significant mortality in Lygus adults compared to controls. Also, male and female Lygus adults exhibited repellence behavior towards endophytic cotton squares containing JG-1 isolate of B. bassiana and to other B. bassiana strains such as NI-8, GHA, and SPE-120. No differences were observed in the survival and development of L. lineolaris second-instar nymphs on endophytic cotton, and no yield differences were observed in the field experiments. [ABSTRACT FROM AUTHOR]

In this study, the transcriptome profiles of tissue–cultured grapevine (Vitis vinifera L. × Vitis labrusca L.: Rose Honey) seedlings inoculated with fungal endophytes Epicoccum layuense R2-21 (Epi R2-21) and Alternaria alternata XHYN2 (Alt XHYN2), were analyzed at three different time points (6 h, 6 d, and 15 d). A total of 4783 differentially expressed genes (DEGs) was found, of which 1853 (6 h), 3878 (6 d), and 4732 (15 d) were differentially expressed relative to those of the control in endophyte Epi R2-21 treatments, while a total of 5898 DEGs, of which 2726 (6 h), 4610 (6 d), and 3938 (15 d) were differentially expressed in endophyte Alt XHYN2 treatments. DEGs enriched in secondary metabolic pathways, plant–pathogen interaction, and hormone signalling were further analysed. The upregulated DEGs in the Epi R2-21 and Alt XHYN2 treatments, both enriched in the Kyoto Encyclopedia of Genes and Genomes (KEGG), were mainly involved in flavonoid biosynthesis, phenylpropanoid biosynthesis, stilbenoid, diarylheptanoid and gingerol biosynthesis, phenylalanine metabolism, and circadian rhythms–plant and plant–pathogen interactions, similar to the trend observed in our previous study conducted on the cultivar 'Cabernet Sauvignon' (Vitis vinifera L.). Taken together with the results obtained from the cultivar 'Cabernet Sauvignon', it was found that tissue-cultured seedlings of the cultivar 'Rose Honey' induced a stronger defence response to fungal endophyte infection than that of the cultivar 'Cabernet Sauvignon', and inoculation with the endophyte Alt XHYN2 triggered a stronger response than inoculation with the endophyte Epi R2-21. In addition, the protein–protein interaction (PPI) network revealed that the genes VIT_16s0100g00910, encoding CHS, and VIT_11s0065g00350, encoding CYP73A, were involved in secondary metabolism and thus mediated in the resistance mechanism of grapevine on both the cultivars. The results showed that inoculation with the endophytes Epi R2-21 and Alt XHYN2 had a great ability to induce defence responses and reprogram the gene expression profiles in different grapevine cultivars, which deepens our knowledge of the interaction between fungal endophytes and grapevine and gives hints for grape quality management in viticulture using candidate fungal endophytes. [ABSTRACT FROM AUTHOR]

This study profiled the various endophytic fungi isolated from the orchid Cymbidium sp. and their L-asparaginase production and antioxidant potential. The L-asparaginase production was first screened through qualitative plate screening then quantified by the Nesslerization method. The antioxidant potential was quantified via the 2,2-diphenyl-1-picrylhydrazyl assay. A total of 30 endophytic fungi were isolated and all fungal isolates exhibited various degrees of radical scavenging activities (45.28% to 76.4%). Isolate Lasiodiplodia theobromae (C11) had the highest antioxidant capacity, represented by the lowest IC50 value (5.75 mg/mL) and highest ascorbic acid equivalent antioxidant capacity value (12.17 mg/g). Additionally, 16 isolates produced L-asparaginase (53.33%), which includes primarily species of Fusarium proliferatum, Fusarium fujikuroi, Fusarium incarnatum, and Fusarium oxysporum. A new isolate has also been discovered from Cymbidium orchid, Buergenerula spartinae (C28), which showed the highest L-asparaginase activity (1.736 unit/mL). These findings supported the postulation that medicinal species of Orchidaceae such as Cymbidium sp. harbor endophytes that are producers of L-asparaginase and antioxidants with various potential applications. [ABSTRACT FROM AUTHOR]

As possible biocontrol agents against soil-borne infections, root endophytic fungi, also known as fungal endophytes, have gained attention. Recently, it has been discovered that fungal endophytes and endophytic fungi found in plant roots are promising biocontrol agents for soil-borne diseases. These fungi can shield plants from the harm that root knots and rot pathogens can cause. They display characteristics crucial for long-term disease control in agriculture, such as the generation of systemic resistance, the production of antifungal metabolites, and the stimulation of plant development. This review examines the different types, underlying mechanisms, and relationships with plant pathogens. Using fungal endophytes as biocontrol agents in agricultural production systems requires standardized selection, application, and evaluation approaches. Fungal endophytes have shown promise as biocontrol agents for preventing the spread of soil-borne diseases, reducing the need for chemical pesticides, and increasing crop yields. Using root endophytic fungi and other fungal endophytes could improve pathogen management and the viability of food production. Supporting ecologically friendly methods and accelerating sustainable agriculture can be accomplished with the use of these helpful fungi. However, further study is required to explore root entophytic fungi and fungal endophytes that can dramatically improve disease management practices and provide more eco-friendly and sustainable agriculture. [ABSTRACT FROM AUTHOR]

Abstract Fungal endophytes, as an untapped resource of glycoside hydrolase biocatalysts, need to be further developed. Mogroside V, the primary active compound in Siraitia grosvenorii fruit, can be converted into other various bioactive mogrosides by selective hydrolysis of glucose residues at C3 and C24 positions. In present study, 20 fungal strains were randomly selected from our endophytic fungal strain library to assess their capability for mogroside V transformation. The results revealed that relatively high rate (30%) endophytic fungal strains exhibited transformative potential. Further analysis indicated that endophytic fungi could produce abundant mogrosides, and the pathways for biotransforming mogroside V showed diverse. Among the given fungal endophytes, Aspergillus sp. S125 almost completely converted mogroside V into the end-products mogroside II A and aglycone within just 2 days of fermentation; Muyocopron sp. A5 produced rich intermediate products, including siamenoside I, and the end-product mogroside II E. Subsequently, we optimized the fermentation conditions for Aspergillus sp. S125 and Muyocopron sp. A5 to evaluate the feasibility of large-scale mogroside V conversion. After optimization, Aspergillus sp. S125 converted 10 g/L of mogroside V into 4.5 g/L of mogroside II A and 3.6 g/L of aglycone after 3 days of fermentation, whereas Muyocopron sp. A5 selectively produced 4.88 g/L of siamenoside I from 7.5 g/L of mogroside V after 36 h of fermentation. This study not only identifies highly effective biocatalytic candidates for mogrosides transformation, but also strongly suggests the potential of plant endophytic fungi as valuable resources for the biocatalysis of natural compounds.

Endophytes represent a diverse domain of microorganisms with immense biotechnological potentialities. Metabolites from endophytes, especially fungi, are useful in industrial as well as pharmaceutical aspects. Here, endophytic fungal isolates of Andrographis paniculata collected from the Tapobon, Junglemahal region of West Bengal, India, have been studied for their hydrolyzing enzyme production abilities. Out of eighty-one isolates, twenty-one were positive for amylase, protease, lipase, laccase, and tannase action. Microscopic features of positive isolates revealed that the enzyme producers were Aspergillus sp., Fusarium sp., Alternaria sp., Trichoderma sp., Exerohilum sp., Nigrospora sp., Curvularia sp., Cladosporium sp., Cochliobolus sp., Tricothecium sp., Penicillium sp., Verticillium sp., and Cephalosporium sp. The amylolytic activity was remarkable in the case of endophytic Aspergillus sp. and Fusarium sp. Also, Aspergillus sp. and Alternaria sp. had proteolytic activity. Aspergillus sp., Mycelia sterilia-2, and Trichoderma sp. were potent lipase producers. Along with Exerohilum sp. endophytic Aspergillus sp. had positive laccase activity. The tannic acid degrading activity was highest for Aspergillus sp. APL11 followed by Helicosporium sp. and Fusarium sp. Tannase producing ability of Aspergillus sp. was optimized and an incubation time- 96h, incubation temperature- 29°C, initial medium pH- 6.5, carbon source- glucose, and nitrogen source- NaNO3 exhibited a two-fold scale-up of (2.83±0.05 u mL-1) in tannase action. These enzymes offer eco-friendly and efficient solutions across a wide range of industrial processes including food production, textile processing, and pharmaceutical synthesis. Fungal endophytes of medicinal plants act as an alternative source for hydrolysing enzymes.

The secondary metabolome of Nemania diffusa, isolated as an ash endophytic fungus, was analyzed in detail. From its cultures, a previously undescribed cytochalasin 1 was isolated using preparative HPLC, together with six known congeners: 18-dehydroxy-cytochalasin E (2), cytochalasins Z7 (3), Z8 (4), and E (5), 18-dehydroxy-17-didehydro-cytochalasin E (6), and K Steyn (7). The structures of these compounds were determined using data from high-resolution mass spectrometry (HR-MS), in combination with 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. Metabolites 1–4 share a characteristic 12-membered lactone moiety, placing them within a rarely examined cytochalasin subclass. Thus, the compounds were incorporated into our ongoing screening campaign to study the structure–activity relationship of this metabolite family. We initially determined their cytotoxicity in eukaryotic mouse fibroblast L929 cells using an MTT-based colorimetric assay, and further investigated their effect on the cellular actin dynamics of the human osteosarcoma cell line U-2OS in detail. Unexpectedly, we discovered a high number of irreversible compounds (1, 2, and 4). Additionally, we highlighted specific structural features within the 12-membered cytochalasin subclass that may play a role in directing the reversibility of these compounds.

The causative agent of sooty bark disease, Cryptostroma corticale, has, for some years, caused increased damage to maples (Acer spp.) in Germany and throughout Europe. It has been stated that this pathogen can occur latently in Acer. In this study, the composition of endophytic fungi of woody stem tissues of sycamore (Acer pseudoplatanus) saplings were analysed in order to investigate whether C. corticale is present in young, visually healthy maple trees from natural regeneration. The most abundant taxa of the 30 isolated endophytes were Diaporthe cf. rudis and Petrakia irregularis. An association of five fungal species (Biscogniauxia mediterranea, Coniochaeta velutina, Gibellulopsis catenata, Neocucurbitaria quercina, Tangerinosporium thalitricola) with A. pseudoplatanus was reported for the first time. Cryptostroma corticale was not present in the juvenile sycamore stems. Furthermore, its pathogenicity was studied in comparison to other pathogens associated with A. pseudoplatanus, namely Diplodia mutila, Dothiorella sp., Nectria cinnabarina, Neonectria coccinea, Neonectria punicea and Stegonsporium pyriforme. The longest necroses were induced by C. corticale followed by N. coccinea. In a trial with a C. corticale spore suspension sprayed directly on stem bark, the fungus could be re-isolated from woody tissue, however necroses were evoked only when the bark was wounded prior to infection. The results from the experiments presented here function as additional evidence for the ability of C. corticale to establish endophytically within the host and, in particular, for the ability of the fungus to establish a successful infection/entrance through intact bark. [ABSTRACT FROM AUTHOR]

The main focus of this review is to introduce readers to the fascinating class of lipid molecules known as norsteroids, exploring their distribution across various biotopes and their biological activities. The review provides an in-depth analysis of various modified steroids, including A, B, C, and D-norsteroids, each characterized by distinct structural alterations. These modifications, which range from the removal of specific methyl groups to changes in the steroid core, result in unique molecular architectures that significantly impact their biological activity and therapeutic potential. The discussion on A, B, C, and D-norsteroids sheds light on their unique configurations and how these structural modifications influence their pharmacological properties. The review also presents examples from natural sources that produce a diverse array of steroids with distinct structures, including the aforementioned A, B, C, and D-nor variants. These compounds are sourced from marine organisms like sponges, soft corals, and starfish, as well as terrestrial entities such as plants, fungi, and bacteria. The exploration of these steroids encompasses their biosynthesis, ecological significance, and potential medical applications, highlighting a crucial area of interest in pharmacology and natural product chemistry. The review emphasizes the importance of researching these steroids for drug development, particularly in addressing diseases where conventional medications are inadequate or for conditions lacking sufficient therapeutic options. Examples of norsteroid synthesis are provided to illustrate the practical applications of this research. [ABSTRACT FROM AUTHOR]

Fungal endophytes, as an untapped resource of glycoside hydrolase biocatalysts, need to be further developed. Mogroside V, the primary active compound in Siraitia grosvenorii fruit, can be converted into other various bioactive mogrosides by selective hydrolysis of glucose residues at C3 and C24 positions. In present study, 20 fungal strains were randomly selected from our endophytic fungal strain library to assess their capability for mogroside V transformation. The results revealed that relatively high rate (30%) endophytic fungal strains exhibited transformative potential. Further analysis indicated that endophytic fungi could produce abundant mogrosides, and the pathways for biotransforming mogroside V showed diverse. Among the given fungal endophytes, Aspergillus sp. S125 almost completely converted mogroside V into the end-products mogroside II A and aglycone within just 2 days of fermentation; Muyocopron sp. A5 produced rich intermediate products, including siamenoside I, and the end-product mogroside II E. Subsequently, we optimized the fermentation conditions for Aspergillus sp. S125 and Muyocopron sp. A5 to evaluate the feasibility of large-scale mogroside V conversion. After optimization, Aspergillus sp. S125 converted 10 g/L of mogroside V into 4.5 g/L of mogroside II A and 3.6 g/L of aglycone after 3 days of fermentation, whereas Muyocopron sp. A5 selectively produced 4.88 g/L of siamenoside I from 7.5 g/L of mogroside V after 36 h of fermentation. This study not only identifies highly effective biocatalytic candidates for mogrosides transformation, but also strongly suggests the potential of plant endophytic fungi as valuable resources for the biocatalysis of natural compounds. [ABSTRACT FROM AUTHOR]

Aims: This study aims to determine the antibacterial potential and identify the bioactive compounds of Hypoxylon monticulosum isolated from marine macroalgae Ulva lactuca. Methodology and results: Ulva lactuca was collected from the Desaru coast, Johor, Malaysia and three endophytes were isolated following surface sterilisation. One fungal isolate was further characterised by the morphology of white, yellowish colonies and fibrous with a waxy structure indicative of a member from the genus Hypoxylon. Molecular identification through internal transcribed spacer (ITS) sequence analysis matches the reference sequence with more than ≥98% homology to Hypoxylon monticulosum AS26-D8. Minimum inhibition concentration (MIC) of the fungal ethyl acetate (EA) extract was determined against five human pathogenic bacteria. Wide spectrum antibacterial activity was noted; with MIC against Escherichia coli was 1.25 ± 0 mg/mL, Bacillus subtilis and Enterobacter faecalis both at 5.00 ± 0 mg/mL, and finally, both Staphylococcus aureus and Klebsiella pneumoniae were 10.00 ± 0 mg/mL, respectively. Bioassay-guided fractionation was performed using solvents of increasing polarities, producing three fractions and analysis by liquid chromatography-mass spectrometry (LC/MS) identified 128 compounds. From these, nine compounds were identified as having biological activities. Dihydrocordoin, D-pantothenoyl-L-cysteine, caffeine and Tumonoic A acid were among the compounds identified as having antibacterial properties. Conclusion, significance and impact of study: Hypoxylon monticulosum from marine source has antibacterial potential owing to the compounds previously reported to display antibacterial and other biological properties. The compounds differ from those previously reported in H. monticulosum from terrestrial sources. [ABSTRACT FROM AUTHOR]

Monk fruit (Siraitia grosvenorii) is an herbaceous perennial vine of the Cucurbitaceae family cultivated commercially mainly in southern China. There is very little information available about the fungal endophytes in monk fruit. In this study, monk fruit plants were grown from seeds in a research greenhouse at Kwantlen Polytechnic University in British Columbia, Canada to explore the abundance and diversity of their fungal endophytes. Fungal endophytes were isolated from seeds, seedlings, mature monk fruit plants, and fruits, and cultured on potato dextrose agar and water agar media. Isolates were identified by microscopic examination and BLAST comparison of ITS sequences to published sequences in GenBank. At least 150 species of fungal endophytes representing 60 genera and 20 orders were recovered from monk fruit tissues. Non‐metric multidimensional scaling (NMDS) was carried out to explore the similarity of fungal communities among roots, stems, leaves, flowers, fruits, and seeds based on fungal orders. Our study showed that monk fruit plants are a rich source of fungal endophytes with the greatest abundance and diversity in leaves. This work has deepened our understanding of the intricate interactions between plants and fungi that sustain ecosystems and underpin plant health and resilience. [ABSTRACT FROM AUTHOR]

Endophytic fungi offer promising alternatives for sustainable plant disease management strategies, often through the production of bioactive secondary metabolites. This study investigated the biocontrol potential of filtrates and extracts, produced under controlled conditions, from Alternaria leptinellae E138 against Pseudomonas syringae in tomato plants under greenhouse conditions. To understand the main mechanisms involved in biocontrol, the direct inhibition of bacterial growth and disruption of quorum sensing activity caused by metabolites were studied in vitro, as well as indirect mechanisms, such as their capacity to produce phytohormone-like substances, nutrient mobilization, and antioxidant activity, which can enhance plant growth and fitness. Moreover, a mass spectrometry analysis was used to tentatively identify the secondary metabolites present in the extract with antimicrobial properties, which could explain the biocontrol effects observed. Mycopriming assays, involving the direct treatment of tomato seeds with the fungal A. leptinellae E138 extracts, produced increased germination rates and seedling vigor in tomato seeds. As another treatment, postemergence application of the extracts in greenhouse conditions significantly improved plant health and resulted in a 41% decrease in disease severity. Overall, this study underscores the potential of A. leptinellae E138 extract as a plant growth promoter with biocontrol capabilities, offering promising avenues for sustainable plant disease management. [ABSTRACT FROM AUTHOR]

In the current study, endophytic Aspergillus hiratsukae was used for the biosynthesis of silver nanoparticles (Ag-NPs) for the first time. The characterizations were performed using X ray diffraction (XRD), Transmission electron microscopy (TEM), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-- EDX), Dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and UV--Vis spectroscopy. The obtained results demonstrated the successful formation of crystalline, spherical Ag-NPs with particle diameters ranging from 16 to 31nm. The FT-IR studied and displayed the various functional groups involved, which played a role in capping and reducing agents for Ag-NPs production. The SEM--EDX revealed that the main constituent of the AS-formed sample was primarily Ag, with a weight percentage of 64.2%. The mycosynthesized Ag-NPs were assessed for antimicrobial as well as photocatalytic activities. The antimicrobial results indicated that the synthesized Ag-NPs possess notable antibacterial efficacy against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli, with minimum inhibitory concentrations (MICs) of Ag-NPs ranging from 62.5 to 250 μg/mL. Moreover, the biosynthesized Ag-NPs demonstrated weak antifungal activity against Aspergillus brasiliensis and Candida albicans, with MICs of 500 and 1,000 μg/mL, respectively. In addition, the mycosynthesized Ag- NPs exhibited photocatalytic activity toward acid black 2 (nigrosine) dye under both light and dark stimulation. Notably, After 300min exposure to light, the nigrosine dye was degraded by 93%. In contrast, 51% degradation was observed after 300min in darkness. In conclusion, Ag-NPs were successfully biosynthesized using endophytic A. hiratsukae and also exhibited antimicrobial and photocatalytic activities that can be used in environmental applications. [ABSTRACT FROM AUTHOR]

This study reports the antioxidant potential and L-asparaginase production of culturable fungal endophytes from Dendrobium orchids in Malaysia. Twenty-nine isolates were screened using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay to determine their free radical scavenging activities and antioxidant capacity (IC50 and AEAC). L-asparaginase production of fungal endophytes was detected by the qualitative plate assay, and the enzyme activities estimated via the Nesslerization method. All 29 endophytic isolates exhibited various degrees of radical scavenging activities (35.37%–77.23%), with Fusarium fujikuroi (D1) identified as having the highest antioxidant capacity (IC50 6.097 mg/mL) and the highest AEAC value (11.55  mg/g). For L-asparaginase production, the majority of the isolates (89.66%) showed positive results, especially among the culturable species of Fusarium, Trichoderma , and Daldinia. Most Fusarium spp. were able to produce L-asparaginase (80.77%), but the highest L-asparaginase activity was detected in Daldinia eschscholtzii (D14) with 2.128 units/mL. Results from this study highlighted the potential of endophytic fungi from medicinal orchids (Dendrobium sp.) as natural sources of bioactive compounds to be developed into novel antioxidants and anticancer drugs. [ABSTRACT FROM AUTHOR]

This article explores the diverse array of biologically active compounds derived from microbial symbionts, particularly focusing on the isolation and characterization of diepoxides, highly oxygenated triterpenoids, secosteroids, ergostane-type steroids, and meroterpenoids from various marine and plant-derived fungi. We highlight significant discoveries such as vitamin D variants from fungal species, unique sesterterpenoids from mangrove endophytic fungi, and secosteroids with potential medicinal applications. The study delves into the structural uniqueness and bioactivities of these compounds, including their anti-inflammatory, antibacterial, antifungal, antiviral, and cytotoxic effects. Notable findings include the isolation of compounds with significant activity against cancer cell lines, the inhibition of acetylcholinesterase, and promising antifouling properties. This work underscores the potential of microbial symbionts as a rich source of novel bioactive compounds with diverse therapeutic applications, highlighting the importance of marine and fungal biodiversity in drug discovery and development. [ABSTRACT FROM AUTHOR]

Xylella fastidiosa (Xf) is a global bacterial threat for a diversity of plants, including olive trees. However, current understanding of host responses upon Xf-infection is limited to allow early disease prediction, diagnosis, and sustainable strategies for breeding on plant tolerance. Recently, we identified a major complex trait for early de novo programming, named CoV-MAC-TED, by comparing early transcriptome data during plant cell survival with SARS-CoV-2-infected human cells. This trait linked ROS/RNS balancing during first hours of stress perception with increased aerobic fermentation connected to alpha-tubulin-based cell restructuration and control of cell cycle progression. Furthermore, our group had advanced concepts and strategies for breeding on plant holobionts. Here, we studied tolerance against Xf-infection by applying a CoV-MAC-TED-related gene set to (1) progress proof-of-principles, (2) highlight the importance of individual host responses for knowledge gain, (3) benefit sustainable production of Xf-threatened olive, (4) stimulate new thinking on principle roles of secondary metabolite synthesis and microbiota for system equilibration and, (5) advance functional marker development for resilience prediction including tolerance to Xf-infections. We performed hypothesis-driven complex analyses in an open access transcriptome of primary target xylem tissues of naturally Xf-infected olive trees of the Xf-tolerant cv. Leccino and the Xf-susceptible cv. Ogliarola. The results indicated that cyanide-mediated equilibration of oxygen-dependent respiration and carbon-stress alleviation by the help of increased glycolysis-driven aerobic fermentation paths and phenolic metabolism associate to tolerance against Xf. Furthermore, enhanced alternative oxidase (AOX) transcript levels through transcription Gleichschaltung linked to quinic acid synthesis appeared as promising trait for functional marker development. Moreover, the results support the idea that fungal endophytes strengthen Xf-susceptible genotypes, which lack efficient AOX functionality. Overall, this proof-of-principles approach supports the idea that efficient regulation of the multi-functional AOX gene family can assist selection on multiple-resilience, which integrates Xf-tolerance, and stimulates future validation across diverse systems. [ABSTRACT FROM AUTHOR]

Endophytes represent a diverse domain of microorganisms with immense biotechnological potentialities. Metabolites from endophytes, especially fungi, are useful in industrial as well as pharmaceutical aspects. Here, endophytic fungal isolates of Andrographis paniculata collected from the Tapobon, Junglemahal region of West Bengal, India, have been studied for their hydrolyzing enzyme production abilities. Out of eighty-one isolates, twenty-one were positive for amylase, protease, lipase, laccase, and tannase action. Microscopic features of positive isolates revealed that the enzyme producers were Aspergillus sp., Fusarium sp., Alternaria sp., Trichoderma sp., Exerohilum sp., Nigrospora sp., Curvularia sp., Cladosporium sp., Cochliobolus sp., Tricothecium sp., Penicillium sp., Verticillium sp., and Cephalosporium sp. The amylolytic activity was remarkable in the case of endophytic Aspergillus sp. and Fusarium sp. Also, Aspergillus sp. and Alternaria sp. had proteolytic activity. Aspergillus sp., Mycelia sterilia-2, and Trichoderma sp. were potent lipase producers. Along with Exerohilum sp. endophytic Aspergillus sp. had positive laccase activity. The tannic acid degrading activity was highest for Aspergillus sp. APL11 followed by Helicosporium sp. and Fusarium sp. Tannase producing ability of Aspergillus sp. was optimized and an incubation time-96h, incubation temperature-29°C, initial medium pH-6.5, carbon source-glucose, and nitrogen source-NaNO3 exhibited a two-fold scale-up of (2.83±0.05 u mL-1) in tannase action. These enzymes offer eco-friendly and efficient solutions across a wide range of industrial processes including food production, textile processing, and pharmaceutical synthesis. Fungal endophytes of medicinal plants act as an alternative source for hydrolysing enzymes. [ABSTRACT FROM AUTHOR]

Fungal endophytes are reservoirs of bioactive molecules that impart therapeutic potential to indigenous medicinal plants. Since new strains of microbial pathogens are evolving with their ability towards drug resistance, herbal phytometabolites are a new lead for exploiting their potential in the field of medicine. The ethnobotanical literature and scientific potential of medicinal plants in traditional medicine have always developed interest in the piqued for new bioactive compounds produced by endophytic bacteria and fungi. The endophytic association of medicinal plants imparts therapeutic attributes to the plant metabolites. Endophytes include bacteria, viruses, and fungi, but as per the literature, fungal endophytes are more promising for exploring the potential compounds, they synthesize in host plants. The occurrence of endophytic associations is found in almost all plant species, and their roles are well established. This association is present in roots, stems, and leaves, these microbial endophytes enhance growth, yield, stress tolerance, control plant pathogens, and manage diseases naturally. In the present review, the potential benefits of endophytes such as anti-inflammatory, antimicrobial, anticancer, antidepressants, immunosuppressant, etc. are discussed.

Abstract The root nodules of actinorhizal plants are home to nitrogen‐fixing bacterial symbionts, known as Frankia, along with a small percentage of other microorganisms. These include fungal endophytes and non‐Frankia bacteria. The taxonomic and functional diversity of the microbial consortia within these root nodules is not well understood. In this study, we surveyed and analyzed the cultivable, non‐Frankia fungal and bacterial endophytes of root nodules from red and Sitka alder trees that grow together. We examined their taxonomic diversity, co‐occurrence, differences between hosts, and potential functional roles. For the first time, we are reporting numerous fungal endophytes of alder root nodules. These include Sporothrix guttuliformis, Fontanospora sp., Cadophora melinii, an unclassified Cadophora, Ilyonectria destructans, an unclassified Gibberella, Nectria ramulariae, an unclassified Trichoderma, Mycosphaerella tassiana, an unclassified Talaromyces, Coniochaeta sp., and Sistotrema brinkmanii. We are also reporting several bacterial genera for the first time: Collimonas, Psychrobacillus, and Phyllobacterium. Additionally, we are reporting the genus Serratia for the second time, with the first report having been recently published in 2023. Pseudomonas was the most frequently isolated bacterial genus and was found to co‐inhabit individual nodules with both fungi and bacteria. We found that the communities of fungal endophytes differed by host species, while the communities of bacterial endophytes did not.

Societal Impact Statement Climate change is predicted to increase drought and soil salinity in Mediterranean‐type ecosystems (MTEs), posing a significant threat to global food security. Genetic modification of crops to counteract this threat is expensive and has not met with universal support, and alternatives are hence needed to enhance crop production in MTEs. Here, fungal endophytes from the Atacama Desert, High Andes and Antarctica inoculated onto three crops were found to alleviate the negative effects of drought and salinity on plant performance. The study concludes that extremophile endophytes might be used to enhance crop performance as the climate of MTEs changes over future decades. Summary Climate change will curtail the ability to provide sufficient food for our rapidly expanding population. Improvements to crop production in changing environments, particularly Mediterranean‐type ecosystems (MTEs), which are increasingly subjected to drought and salinisation, are hence urgently needed. Here, we explored the possibility that fungal endophytes from extreme environments can be used to enhance crop yield, survival and tolerance to environmental stresses. Plants of lettuce, tomato and bell pepper were inoculated with up to six species of endophytic fungi isolated from the Atacama Desert, the High Andes and Antarctica. They were then exposed in the field for up to 120 days in each of three summers to current climatic conditions or to a future climate scenario simulating increased drought and soil salinisation. Compared with uninoculated plants, the yield and survival of inoculated crops were increased by up to two‐fold under the future climate scenario. These effects were in part attributable to the improved water balance of inoculated crops exposed to drought and salinisation. The inocula also increased the concentrations of total phenols and proline in leaves and decreased lipid peroxidation when plants were subjected to increased aridity and salinity. A mixed inoculum of six endophytes from the extreme environments conferred the most beneficial effects on crop performance, with a commercially available inoculum having fewer positive effects on crops. We conclude that the inoculation of crops with endophytes from extreme environments may be a viable solution to sustaining crop production in MTEs exposed to rapid climate change.

The Red Sea represents a potential ecosystem with very rich biodiversity in the production of unique natural compounds. Recently, fungal secondary metabolites had been a major domain of research in the meadow of natural compounds with special emphasis on fungal strains isolated from marine ecosystems. More than 150 interesting secondary metabolites going with different classes of natural compounds had been reported with potential biological actions as cytotoxic activity with emphasis to the application of different approaches for example OSMAC ( one strain many compounds ) approach. The current review presents a comprehensive report for fungal secondary metabolites isolated from the Red Sea ecosystems either as endophytes from marine invertebrates (for example corals and sponges) and plants for example (algae and mangrove) or as free living strains collected from sea sediments from different locations of Red Sea. Different databases had been utilized including the EKB (Egyptian Knowledge Bank), SciFinder and MarinLit.. In no doubt, the richness of published data directs to the marine fungi's medicinal potential. It will continue to be challenging to incorporate marine fungus into traditional therapy. The clinical environment demonstration of therapeutic activity is a fundamental task for medicine research. For the profit of patients all through the world, it is to be wished that this significant barrier will be removed in the years to arise.

Our research group isolated an endophyte yeast from the endemic plant Echinopsis chiloensis. This yeast, identified as Naganishia sp, produces volatile organic compounds (VOC) with antifungal activity against Botrytis cinerea. Due to the need for alternative control methods for this pathogen, the effect of VOC on B. cinerea was analyzed. On the fourth day of cultivation, in the presence of VOCs, the mycelial growth of B. cinerea stopped. VOCs inhibited 32.8% of the conidia germination and reduced sporulation by 70.6%. These compounds promoted the formation of infection cushions. VOCs caused damage to the cell wall and plasma membrane in B. cinerea. On the other hand, the volatile compounds induced oxidative stress, and led to membrane lipid peroxidation after 16 and 24 h of incubation in the presence of VOCs, because an increased level of malondialdehyde content was observed. These compounds exerted a fungistatic effect on B. cinerea. The volatile compounds emitted by Naganishia sp were identified by gas chromatography coupled with mass spectrometry as 3-methylbutyl acetate, ethylbenzene, 1-ethyl-3-methylbenzene, 2-phenylethanol, 2-heptanone and (5E)-6,10-dimethylundeca-5,9-dien-2-one. The most abundant volatile compound, 2-phenylethanol, inhibited the mycelial growth of B. cinerea with an IC50 value of 0.21 µL mL−1. The effect of this pure compound was also fungistatic. Finally, it was shown that volatile compounds decreased the severity of B. cinerea infection in tomatoes and grapes by 64.7 and 43,1%, respectively. This is the first report identifying volatile compounds emitted by a Naganishia sp. and describing their mode of action against B. cinerea.

ABSTRACTFungal endophytes have emerged as a promising source of secondary metabolites with significant potential for various applications in the field of biomedicine. The biosynthetic gene clusters of endophytic fungi are responsible for encoding several enzymes and transcriptional factors that are involved in the biosynthesis of secondary metabolites. The investigation of fungal metabolic potential at genetic level faces certain challenges, including the synthesis of appropriate amounts of chemicals, and loss of the ability of fungal endophytes to produce secondary metabolites in an artificial culture medium. Therefore, there is a need to delve deeper into the field of fungal genomics and transcriptomics to explore the potential of fungal endophytes in generating secondary metabolites governed by biosynthetic gene clusters. The silent biosynthetic gene clusters can be activated by modulating the chromatin structure using chemical compounds. Epigenetic modification plays a significant role by inducing cryptic gene responsible for the production of secondary metabolites using DNA methyl transferase and histone deacetylase. CRISPR-Cas9-based genome editing emerges an effective tool to enhance the production of desired metabolites by modulating gene expression. This review primarily focuses on the significance of epigenetic elicitors and their capacity to boost the production of secondary metabolites from endophytes. This article holds the potential to rejuvenate the drug discovery pipeline by introducing new chemical compounds.

Abstract Monk fruit (Siraitia grosvenorii) is an herbaceous perennial vine of the Cucurbitaceae family cultivated commercially mainly in southern China. There is very little information available about the fungal endophytes in monk fruit. In this study, monk fruit plants were grown from seeds in a research greenhouse at Kwantlen Polytechnic University in British Columbia, Canada to explore the abundance and diversity of their fungal endophytes. Fungal endophytes were isolated from seeds, seedlings, mature monk fruit plants, and fruits, and cultured on potato dextrose agar and water agar media. Isolates were identified by microscopic examination and BLAST comparison of ITS sequences to published sequences in GenBank. At least 150 species of fungal endophytes representing 60 genera and 20 orders were recovered from monk fruit tissues. Non‐metric multidimensional scaling (NMDS) was carried out to explore the similarity of fungal communities among roots, stems, leaves, flowers, fruits, and seeds based on fungal orders. Our study showed that monk fruit plants are a rich source of fungal endophytes with the greatest abundance and diversity in leaves. This work has deepened our understanding of the intricate interactions between plants and fungi that sustain ecosystems and underpin plant health and resilience.