Fungal Pathogens Research Articles

Exploring the Modern Fungicides for the In vitro Management of Pokkah Boeng Disease of Maize Caused by Fusarium verticillioides (SACC.) Nirenberg

Pokkah boeng disease caused by Fusarium verticillioides is an emerging fungal disease affecting maize recently leading to substantial yield losses. The increasing resistance of pathogens to older fungicides, along with environmental concerns, underscores the need for new management strategies that incorporates next-generation fungicides. In response to this challenge, a comprehensive and systematic survey was conducted in 2022-23 across the Dharwad district of Karnataka. The survey documented disease symptoms such as chlorosis at the base of leaves, malformation and twisting of the foliage. The pathogen was isolated and confirmed as F. verticillioides through molecular diagnosis. In the present study, the pathogen was tested for in vitro efficacy of modern fungicides at three different concentrations viz., 0.1, 0.15 and 0.2 per cent using poisoned food technique. In vitro testing of new generation fungicides revealed that, Tebuconazole 25.9%EC and combinations fungicides viz., Carbendazim 12%+Mancozeb 63%WP and Trifloxystrobin 25% + Tebuconazole 50%WG resulted in 100 per cent inhibition of the mycelial growth of the pathogen. Hexaconazole 5%SC, Azoxystrobin 23%SC, Trifloxystrobin 25%SC, Tricyclazole 18%+Mancozeb 62% WP and Azoxystrobin 18.2%+Difenoconazole 11.4%SC inhibited mycelial growth by 99.15, 85.49, 85.57 93.08 and 86.87 per cent, respectively. The mycelial growth in fungicide-treated media appeared either fluffy or cottony. Among the fungicides tested, Carbendazim 12% + Mancozeb 63% WP, Trifloxystrobin 25% + Tebuconazole 50% WG, and Tebuconazole 25.9%EC demonstrated 100 per cent efficacy in inhibiting pathogen mycelial growth, even at a low concentration of 0.1%. These results suggest a promising direction for disease management, while the other fungicides tested were found to be less effective.

Antifungal activity of grape associated bacterial endophytes against pathogenic fungi

Antifungal activity of grape associated bacterial endophytes against pathogenic fungi

One New Quinazoline-Containing Diketopiperazine Isolated from the Marine-Sponge-Derived Fungus Penicillium sp. SCSIO41043.

One new quinazoline-containing diketopiperazine (1), along with 24 known compounds including nine alkaloids (2-9, and 25), thirteen lactones (10-22), aspterric acid (23), and catechol (24), were isolated from the marine sponge-derived Penicillium sp. SCSIO41043. Their planar structures were unequivocally elucidated by spectroscopic analysis. The absolute configuration of 1 was determined by a comparison of reported and experimental electronic circular dichroism (ECD) spectra. Compound 16 was found to notably inhibit the growth of five pathogenic bacteria and fungi with MIC values ranging from 0.5-16.0 μg/mL. Compounds 7, 17, 20, and 22 demonstrated moderate activity against Micrococcus luteus with MIC values ranging from 35.6 to 71.1 μg/mL. Moreover, 1-3 displayed different degrees of antioxidant activity with EC50 values of 0.98, 0.60, 0.46 mg/mL, respectively.

Application and antagonistic mechanisms of atoxigenic Aspergillus strains for the management of fungal plant diseases.

This review covers, for the first time, all methods based on the use of Aspergillus strains as biocontrol agents for the management of plant diseases caused by fungi and oomycetes. Atoxigenic Aspergillus strains have been screened in a variety of hosts, such as peanuts, maize kernels, and legumes, during the preharvest and postharvest stages. These strains have been screened against a wide range of pathogens, such as Fusarium, Phytophthora, and Pythium species, suggesting a broad applicability spectrum. The highest efficacies were generally observed when using non-toxigenic Aspergillus strains for the management of mycotoxin-producing Aspergillus strains. The modes of action included the synthesis of antifungal metabolites, such as kojic acid and volatile organic compounds (VOCs), secretion of hydrolytic enzymes, competition for space and nutrients, and induction of disease resistance. Aspergillus strains degraded Sclerotinia sclerotiorum sclerotia, showing high control efficacy against this pathogen. Collectively, although two Aspergillus strains have been commercialized for aflatoxin degradation, a new application of Aspergillus strains is emerging and needs to be optimized.

Biosynthesis and Signaling of Strigolactones Act Synergistically With That of ABA and JA to Enhance Verticillium dahliae Resistance in Cotton (Gossypium hirsutum L.).

Verticillium wilt (VW) caused by the soil-borne fungal pathogen Verticillium dahliae reduces cotton productivity and quality. Numerous studies have explored the genetic and molecular mechanisms regulating VW resistance in cotton, but the role and mechanism of strigolactone (SL) is still elusive. We investigated the function of SL in cotton's immune response to V. dahliae infection by exogenously applying SL analog, blocking or enhancing biosynthesis of endogenous SLs in combination with comparative transcriptome analysis and by exploring cross-talk between SL and other phytohormones. Silencing GhDWARF27 and applying the SL analog GR24 or overexpressing GhDWARF27 decreased and enhanced V. dahliae resistance, respectively. Transcriptome analysis revealed SL-mediated activation of abscisic acid (ABA) and jasmonic acid (JA) biosynthesis and signaling pathways. Enhanced ABA biosynthesis and signaling led to increased activity of antioxidant enzymes and reduced buildup of excess reactive oxygen species. Enhanced JA biosynthesis and signaling facilitated transcription of JA-dependent disease resistance genes. One of the components of the SL signal transduction pathway, GhD53, was found to interact with GhNCED5 and GhLOX2, the key enzymes of ABA and JA biosynthesis, respectively. We revealed the molecular mechanism underlying SL-enabled V. dahliae resistance and provided potential solutions for improving VW resistance in cotton.

Clonostachys rosea, a Pathogen of Brown Rot in Gastrodia elata in China

Gastrodia elata, commonly known as Tian Ma, is a perennial mycoheterotrophic orchid. Qianyang Tian Ma (QTM), a geographical indication agricultural product from Hongjiang City, Hunan Province, China, is primarily characterized by the red variety, G. elata f. elata. A severe outbreak of tuber brown rot disease was documented in QTM during the harvesting season in Hunan. The fungal pathogen associated with the disease was isolated on potato saccharose agar (PSA) and identified through morphological and phylogenetic analyses. Pathogenicity tests were performed on healthy tubers of G. elata f. elata. The results showed that the representative isolate, named TMB, produced white hyphal colonies with a ring structure, broom-like phialides, partially curved ellipsoidal conidia, and orange–yellow spherical ascocarps on PSA. Phylogenetic analysis of the ITS, LSU, rpb2 and tub2 sequences using Bayesian and maximum-likelihood methods identified the isolate TMB as Clonostachys rosea, based on morphological and phylogenetic data. Pathogenicity tests revealed typical disease symptoms on healthy G. elata tubers 15 days post-inoculation with the isolate TMB. C. rosea is known to cause diseases in economically important crops, but there are no reports of its occurrence on G. elata f. elata in China. This study provides valuable insights into the occurrence, prevention, and control of brown rot disease in G. elata f. elata.

Diversity and impact of single-stranded RNA viruses in Czech Heterobasidion populations.

Heterobasidion annosum sensu lato comprises some of the most devastating pathogens of conifers. Exploring virocontrol as a potential strategy to mitigate economic losses caused by these fungi holds promise for the future. In this study, we conducted a comprehensive screening for viruses in 98 H. annosum s.l. specimens from different regions of Czechia aiming to identify viruses inducing hypovirulence. Initial examination for dsRNA presence was followed by RNA-seq analyses using pooled RNA libraries constructed from H. annosum and Heterobasidion parviporum, with diverse bioinformatic pipelines employed for virus discovery. Our study uncovered 25 distinct ssRNA viruses, including two ourmia-like viruses, one mitovirus, one fusarivirus, one tobamo-like virus, one cogu-like virus, one bisegmented narna-like virus and one segment of another narna-like virus, and 17 ambi-like viruses, for which hairpin and hammerhead ribozymes were detected. Coinfections of up to 10 viruses were observed in six Heterobasidion isolates, whereas another six harbored a single virus. Seventy-three percent of the isolates analyzed by RNA-seq were virus-free. These findings show that the virome of Heterobasidion populations in Czechia is highly diverse and differs from that in the boreal region. We further investigated the host effects of certain identified viruses through comparisons of the mycelial growth rate and proteomic analyses and found that certain tested viruses caused growth reductions of up to 22% and significant alterations in the host proteome profile. Their intraspecific transmission rates ranged from 0% to 33%. Further studies are needed to fully understand the biocontrol potential of these viruses in planta.IMPORTANCEHeterobasidion annosum sensu lato is a major pathogen causing significant damage to conifer forests, resulting in substantial economic losses. This study is significant as it explores the potential of using viruses (virocontrol) to combat these fungal pathogens. By identifying and characterizing a diverse array of viruses in H. annosum populations from Czechia, the research opens new avenues for biocontrol strategies. The discovery of 25 distinct ssRNA viruses, some of which reduce fungal growth and alter proteome profiles, suggests that these viruses could be harnessed to mitigate the impact of Heterobasidion. Understanding the interactions between these viruses and their fungal hosts is crucial for developing effective, environmentally friendly methods to protect conifer forests and maintain ecosystem health. This study lays the groundwork for future research on the application of mycoviruses in forest disease management.

Design, Synthesis, Antifungal Evaluation, and Three-Dimensional Quantitative Structure-Activity Relationship of Novel 5-Sulfonyl-1,3,4-thiadiazole Flavonoids.

Plant pathogenic fungi frequently disrupt the normal physiological and biochemical functions of plants, leading to diseases, compromising plant health, and ultimately reducing crop yield. This study aimed to address this challenge by identifying antifungal agents with innovative structures and novel mechanisms of action. We designed and synthesized a series of flavonoid derivatives substituted with 5-sulfonyl-1,3,4-thiadiazole and evaluated their antifungal activity against five phytopathogenic fungi. Most flavonoid derivatives demonstrated excellent antifungal activity against Botrytis cinerea (B. cinerea), Alternaria solani (A. solani), Rhizoctorzia solani (R. solani), Fusarium graminearum (F. graminearum), and Colletotrichum orbiculare (C. orbiculare). Specifically, the EC50 values of 38 target compounds against R. solani were below 4 μg/mL, among which the compounds C13 (EC50 = 0.49 μg/mL), C15 (EC50 = 0.37 μg/mL), and C19 (EC50 = 0.37 μg/mL) had the most prominent antifungal activity, superior to that of the control drug carbendazim (EC50 = 0.52 μg/mL). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of the cellular ultrastructures of R. solani mycelia and cells after treatment with the compound C19 revealed sprawling growth of hyphae, a distorted outline of their cell walls, and reduced mitochondrial numbers. Studying the 3D-QSAR between the molecular structure and antifungal activity of 5-sulfonyl-1,3,4-thiadiazole-substituted flavonoid derivatives could significantly improve conventional drug molecular design pathways and facilitate the development of novel antifungal leads.

Design, Bioactivity, and Action Mechanism of Pyridinecarbaldehyde Phenylhydrazone Derivatives with Broad-Spectrum Antifungal Activity.

Replacing old pesticides with new pesticide varieties has been the main means to solve pesticide resistance. Therefore, it is necessary to research and develop new antifungal agents for plant protection. In this study, a series of pyridinecarbaldehyde phenylhydrazone derivatives were designed and evaluated for their inhibition activity on plant pathogenic fungi to search for novel fungicide candidates. Picolinaldehyde phenylhydrazone (1) and nicotinaldehyde phenylhydrazone (2) were identified as promising antifungal lead scaffolds. The 4-fluorophenylhydrazone derivatives (1a and 2a) of 1 and 2 showed highly effective and broad-spectrum inhibition activity in vitro on 11 phytopathogenic fungi with EC50 values of 0.870-3.26 μg/mL, superior to the positive control carbendazim in most cases. The presence of the 4-fluorine atom on the phenyl showed a remarkable activity enhancement effect. Compound 1a at 300 μg/mL provided almost complete protection against infection of Alternaria solani on tomatoes over the post-treatment 9 days and high safety to germination of plant seeds. Furthermore, 1a showed strong inhibition activity with an IC50 value of 0.506 μg/mL on succinate dehydrogenase in A. solani. Molecular docking showed that both 1a and 2a can well bind to the ubiquinone-binding region of SDH by the conventional hydrogen bond, carbon-hydrogen bond, π-π or π-amide interaction, π-alkyl interaction, X---F (X = N, C, or H) interaction, and van der Waal forces. Meanwhile, scanning and transmission electron analysis displayed that 1a destroyed the morphology of mycelium and the structure of the cell membrane of A. solani. Fluorescent staining analysis revealed that 1a changed the mitochondrial membrane potential and cell membrane permeability. Thus, pyridinecarbaldehyde phenylhydrazone compounds emerged as novel antifungal lead scaffolds, and 1a and 2a can be considered promising candidates for the development of new agricultural fungicides.

Editorial: Invasive fungal diseases: pathogen detection and diagnosis development

Editorial: Invasive fungal diseases: pathogen detection and diagnosis development

Specificity of Membrane-Associated J-Domain Protein, Caj1, in Amphotericin B Tolerance in Budding Yeast.

Hsp70:J-domain protein (JDP) machineries play pivotal roles in maintaining cellular proteostasis and governing various aspects of fungal physiology. While Hsp70 is known for its involvement in conferring tolerance to diverse antifungal drugs, the specific contribution of JDPs remains unclear. In this study, we examined the sensitivity of cytosolic JDP deletion strains of budding yeast to amphotericin B (AmB), a polyene antifungal agent widely utilized in fungal disease treatment due to its ability to disrupt the fungal plasma membrane (PM). Deleting Caj1, a PM-associated class II JDP, heightened susceptibility to AmB, and the protection conferred by Caj1 against AmB necessitated both its N-terminal J-domain and C-terminal lipid binding domain. Moreover, Caj1 deficiency compromised PM integrity as evidenced by increased phosphate efflux and exacerbated AmB sensitivity, particularly at elevated temperatures. Notably, phytosphingosine (PHS) addition as well as overexpression of PMP3, a positive PM integrity regulator, significantly rescued AmB sensitivity of caj1Δ cells. Our results align with the notion that Caj1 associates with the PM and cooperates with Hsp70 to regulate PM proteostasis, thereby influencing PM integrity in budding yeast. Loss of Caj1 function at the PM compromises PM protein quality control, thereby rendering yeast cells more susceptible to AmB.

Gene Editing for Disease Resistance in Crops: Success Stories and Challenges

Gene editing has emerged as a transformative tool in modern agriculture, offering new avenues for enhancing disease resistance in crops. By precisely modifying the DNA of plants, scientists can develop varieties that are better equipped to withstand the onslaught of pathogens, which pose significant threats to global food security. This article delves into the success stories and challenges associated with gene editing for disease resistance in crops, with a focus on technologies like CRISPR-Cas9, TALENs, and ZFNs. One of the major success stories in this field is the development of disease-resistant varieties of wheat, rice, and tomatoes. For instance, researchers have used CRISPR-Cas9 to create wheat varieties resistant to powdery mildew, a devastating fungal disease. Similarly, gene editing has enabled the development of rice strains with enhanced resistance to bacterial blight, a disease that can lead to significant yield losses. In tomatoes, gene editing has been employed to confer resistance against the Tomato Yellow Leaf Curl Virus, which severely affects tomato production worldwide. These achievements underscore the potential of gene editing to create crops that are not only more resilient but also capable of maintaining high yields under disease pressure. However, the application of gene editing in crop disease resistance is not without challenges. One of the primary concerns is the regulatory landscape, which varies significantly across different countries. While some nations have embraced gene-edited crops, others have imposed strict regulations, treating them similarly to genetically modified organisms (GMOs). This inconsistency can hinder the global deployment of disease-resistant crops and create trade barriers. Additionally, there are concerns related to off-target effects, where unintended changes in the genome may occur, potentially leading to unintended consequences in the plant's growth or ecological interactions.

Progress on nonculture based diagnostic tests for invasive mould infection.

This review describes the current status of diagnosing invasive mould disease and Pneumocystis pneumonia using nonconventional diagnostics methods. There has been significant development in the range of nonculture mycological tests. Lateral flow tests (LFTs) for diagnosing aspergillosis complement galactomannan ELISA testing, and LFTs for other fungal diseases are in development. Rapid and low through-put B-D-Glucan assays increase access to testing and there has been significant progress in the standardization/development of molecular tests. Despite this, no single perfect test exists and combining tests (e.g., antigen and molecular testing) is likely required for the optimal diagnosis of most fungal diseases. Based on established clinical performance few mycological tests can be used alone for optimal diagnosis of fungal disease (FD) and combining tests, including classical approaches is the preferred route for confirming and excluding disease. Next-generation sequencing will likely play an increasing role in how we diagnose disease, but optimization, standardization and validation of the entire molecular process is needed and we must consider how host biomarkers can stratify risk. Given the burden of FD in low- and medium-income countries, improved access to novel but more so existing diagnostic testing is critical along with simplification of testing processes.

Plasmodiophora brassicae effector PbPE23 induces necrotic responses in both host and non-host plants.

Plasmodiophora brassicae is an obligate biotroph that causes clubroot disease in cruciferous plants, including canola and Arabidopsis. In contrast to most known bacterial, oomycete and fungal pathogens that colonize at the host apoplastic space, the protist P. brassicae establishes an intracellular colonization within various types of root cells and secretes a plethora of effector proteins to distinct cellular compartments favourable for survival and growth of the pathogen during pathogenesis. Identification and functional characterization of P. brassicae effectors has been hampered by the limited understanding of this unique pathosystem. Here, we report a P. brassicae effector, PbPE23, containing a Ser/Thr kinase domain, that induces necrosis after heterologous expression by leaf infiltration in both host and non-host plants. While PbPE23 is an active kinase, the kinase activity itself is not required for triggering the necrosis in plants. PbPE23 shows a nucleocytoplasmic localization in Nicotiana benthamiana and its N-terminal 25TPdPAQKQ32 sequence, resembling the contiguous hydrophilic TPAP motif and Q-rich region in many Nep1-like proteins (NLPs) from plant-associated microbes, is required for the induction of necrosis. Further, transcript profiling of PbPE23 reveals its high expression at the transition stages from primary to secondary infection, suggesting its potential involvement in the development of clubroot disease.

Transcriptome Mining, Identification and In silico Characterization of Thaumatin-Like Protein Sequences from Mentha Longifolia

Background: Thaumatin-like proteins (TLPs) constitute the PR-5 family of plant pathogenesis- related (PR) proteins and are responsible for host defense and various growth and development- related processes. Mints (Mentha sp.) are essential oil-bearing plants, mainly affected by water availability and fungal pathogens. Objective: Identification of candidate TLPs in Mentha longifolia that may help to counter pathogen infection Methods: Several bioinformatics procedures were used to identify TLP gene sequences from M. longifolia and to characterize them for nucleotide length and composition, their translated proteins, subcellular location, signal peptides, post translational modifications, allergenicity potential, evolutionary relatedness, and miRNA targeting. Result: 19 TLP candidates were identified in M. longifolia (Mlo_TLP001 - Mlo_TLP0019) annotating the available transcriptome data. The molecular mass of Mlo_TLPs ranged between 35.43 kDa - 12.79 kDa. Expression analysis of the Mlo_TLPs revealed that Mlo_TLP003, 006, 008, 010, 012, 013, 014, and 018 were upregulated in M. longifolia stem as compared to the root under control conditions. Further, the analysis of control and V. dahliae infected M. longifolia plants has shown Mlo_TLP006 to be upregulated in both the infected stem and root tissues as compared to the control. Conclusion: Mlo_TLP006 is a probable candidate that imparts resistance to fungal pathogens in Mentha longifolia

In silico analysis of secreted effectorome of the rubber tree pathogen Rigidoporus microporus highlights its potential virulence proteins

Rigidoporus microporus, the causative agent of the white root rot disease of rubber trees, poses a significant threat to natural rubber production worldwide. Understanding the molecular mechanisms facilitating its pathogenicity would be crucial for developing effective disease management strategies. The pathogen secretes effector proteins, which play pivotal roles in modulating host immune responses and infection. In this study, in silico analyses identified 357 putative secreted effector proteins from the R. microporus genome. These were then integrated into previous RNA-seq data obtained in response to rubber tree latex exposure. Annotation of putative effectors suggested the abundance of proteins in several families associated with the virulence of R. microporus, especially hydrophobin proteins and glycoside hydrolase (GH) proteins. The contribution of secreted effectors to fungal pathogenicity was discussed, particularly in response to rubber tree latex exposure. Some unknown highly expressed effectors were predicted for the protein structures, revealing their similarity to aminopeptidase, ubiquitin ligase, spherulin, and thaumatin protein. This integrative study further elucidates the molecular mechanism of R. microporus pathogenesis and offers alternative targets for developing control strategies for managing white root rot disease in rubber plantations.

Sulfated glycosaminoglycans are host epithelial cell targets of the Candida albicans toxin candidalysin.

Candidalysin, a cytolytic peptide produced by the fungal pathogen Candida albicans, is a key virulence factor. However, its host cell targets remain elusive. Here we performed a genome-wide loss-of-function CRISPR screen in the TR146 human oral epithelial cell line and identified that disruption of genes (XYLT2, B3GALT6 and B3GAT3) in glycosaminoglycan (GAG) biosynthesis conferred resistance to damage induced by candidalysin and live C. albicans. Surface plasmon resonance and atomic force and electron microscopy indicated that candidalysin binds to sulfated GAGs, facilitating its enrichment on the host cell surface. Adding exogenous sulfated GAGs or the analogue dextran sulfate protected cells against candidalysin-induced damage. Dextran sulfate also inhibited C. albicans invasion and fungal-induced epithelial cell cytokine production. In mice with vulvovaginal candidiasis, topical dextran sulfate administration reduced intravaginal tissue damage and inflammation. Collectively, sulfated GAGs are epithelial cell targets of candidalysin and can be used therapeutically to protect cells from candidalysin-induced damage.

Microbial production of 5-epi-jinkoheremol, a plant-derived antifungal sesquiterpene.

Synthetic biology using microbial chassis is emerging as a powerful tool for the production of natural chemicals. In the present study, we constructed a microbial platform for the high-level production of a sesquiterpene from Catharanthus roseus, 5-epi-jinkoheremol, which exhibits strong fungicidal activity. First, the mevalonate and sterol biosynthesis pathways were optimized in engineered yeast to increase the metabolic flux toward the biosynthesis of the precursor farnesyl pyrophosphate. Then, the transcription factor Hac1- and m6A writer Ime4-based metabolic engineering strategies were implemented in yeast to increase 5-epi-jinkoheremol production further. Next, protein engineering was performed to improve the catalytic activity and enhance the stability of the 5-epi-jinkoheremol synthase TPS18, resulting in the variant TPS18I21P/T414S, with the most improved properties. Finally, the titer of 5-epi-jinkoheremol was elevated to 875.25 mg/L in a carbon source-optimized medium in shake flask cultivation. To the best of our knowledge, this is the first study to construct an efficient microbial cell factory for the sustainable production of this antifungal sesquiterpene.IMPORTANCEBiofungicides represent a new and sustainable tool for the control of crop fungal diseases. However, hindered by the high cost of biofungicide production, their use is not as popular as expected. Synthetic biology using microbial chassis is emerging as a powerful tool for the production of natural chemicals. We previously identified a promising sesquiterpenoid biofungicide, 5-epi-jinkoheremol. Here, we constructed a microbial platform for the high-level production of this chemical. The metabolic engineering of the terpene biosynthetic pathway was firstly employed to increase the metabolic flux toward 5-epi-jinkoheremol production. However, the limited catalytic activity of the key enzyme, TPS18, restricted the further yield of 5-epi-jinkoheremol. By using protein engineering, we improved its catalytic efficiency, and combined with the optimization of regulation factors, the highest production of 5-epi-jinkoheremol was achieved. Our work was useful for the larger-scale efficient production of this antifungal sesquiterpene.

Exploring the antifungal properties of neem (Azadirachta indica) during: A comprehensive review (2010-2020)

Neem (Azadirachta indica) is a versatile medicinal plant with a long history of use in traditional medicine systems. Among its various therapeutic properties, neem has gained attention for its potent antifungal activity. This paper provides a comprehensive review of the antifungal properties of neem, highlighting its mechanisms of action, efficacy against fungal pathogens, and potential applications in clinical and agricultural settings. By synthesizing findings from a wide range of research studies, this review aims to deepen our understanding of neem's antifungal properties and explore its potential as a natural alternative for combating fungal infections.

Acute toxicity assessment of bioactive constituents from Salvia algeriensis (Desf.) extracts: a promising natural agent against clinical bacterial isolates and pathogenic fungi

Salvia species are emerging as promising therapeutic agents due to their diverse bioactivity against various pathologies. This study was conducted to investigate the phytochemical profile, antimicrobial activity, and acute Toxicity of hydromethanolic extracts from Salvia algeriensis (Desf.) leaves, flowers, and roots. Chemical reaction tests and chromatographic analysis were employed to determine the chemical composition, while microdilution was used to determine the tested microorganisms' minimum inhibitory concentration (MIC). The acute Toxicity of the leaf extract was carried out following the rules and guidelines of OECD 425. Toxicity parameters in Swiss albino mice were evaluated after a single dose of 500 mg/kg and 2000 mg/kg. According to the preliminary phytochemical screening results, terpenoids and polyphenols (flavonoids and tannins) were found in all plant parts, but coumarins were only found in the root extract. The HPLC-DAD analysis revealed the presence of 16 phenolic compounds in varying amounts across the three extracts, of which rosmarinic acid, quercetin, caffeic acid, and 3-hydroxybenzoic acid were the most abundant. Selective antimicrobial activity was noticed, with the root extract demonstrating the most substantial effect against the two fungal strains tested. MIC values ranged from 0.3 to 10 mg/mL, and Gram-positive bacteria generally showedgreater susceptibility compared to Gram-negative bacteria. The LD50 was found to be greater than 2000 mg/kg. There were no overt clinical symptoms of Toxicity. Body weights, organ weights, and temperatures were not significantly altered, and hematological analysis showed no significant differences. Salvia algeriensis (Desf.) extracts emerge as potential candidates for natural, non-toxic antimicrobial agents. Keywords: Acute Toxicity; antimicrobial; HPLC-DAD; polyphenols; Salvia