Fungus Penicillium Chrysogenum Research Articles

Diversity and enzymatic, biosurfactant and phytotoxic activities of culturable Ascomycota fungi present in marine sediments obtained near the South Shetland Islands, maritime Antarctica.

We studied the culturable fungal community recovered from deep marine sediments in themaritime Antarctic, and assessed their capabilities to produce exoenzymes, emulsifiers and metabolites with phytotoxic activity. Sixty-eight Ascomycota fungal isolates were recovered and identified. The most abundant taxon recovered was the yeast Meyerozyma guilliermondii, followed by the filamentous fungi Penicillium chrysogenum, P. cf. palitans, Pseudeurotium cf. bakeri, Thelebolus balaustiformis, Antarctomyces psychrotrophicus and Cladosporium sp. Diversity indices displayed low values overall, with the highest values obtained at shallow depth, decreasing to the deepest location sampled. Only M. guilliermondii and P. cf. palitans were detected in the sediments at all depths sampled, and were the most abundanttaxa at all sample sites. The most abundant enzymes detected were proteases, followed by invertases, cellulases, lipases, carrageenases, agarases, pectinases and esterases. Four isolates showed good biosurfactant activity, particularly the endemic species A. psychrotrophicus. Twenty-four isolates of P. cf. palitans displayed strong phytotoxic activities against the models Lactuca sativa and Allium schoenoprasum. The cultivable fungi recovered demonstrated good biosynthetic activity in the production of hydrolytic exoenzymes, biosurfactant molecules and metabolites with phytotoxic activity, reinforcing the importance of documenting the taxonomic, ecological and biotechnological properties of fungi present in deep oceanic sediments of the Southern Ocean.

Biodeterioration of Cement and Cement-Polymer Mortars: Analysis of the Influence of the Structure and Distribution of Pores on the Humidity of Mortars Exposed to the Biological Environment.

The biodegradation of building materials refers to the problem of loss of performance due to biological agents, mainly dry rot fungi, moulds (filamentous fungi), bacteria and insects. Biocorrosion not only leads to the damage and deterioration of building materials, but can also pose a direct threat to human health. Inorganic building materials are a difficult substrate for microorganisms because they need food sources for their metabolism. However, they become colonised by microorganisms. In this paper, the effect of mould fungi on the moisture content and structure of CEM I and CEM I cement-polymer mortars with a 5% polysiloxane latex admixture was analysed. The analysis was carried out after 15 months of exposure to the biological environment. It was found that the cementitious materials were susceptible to the corrosive environment in the form of the filamentous fungi Penicillium chrysogenum and Cladosporium herbarum. It was also found that, after 15 months of exposure to mould fungi, CEM I cementitious materials without admixtures were slightly less susceptible to mould fungi than CEM I with the addition of a 5% polysiloxane admixture.

Antimicrobial Effect of Submicron Complex Oxide Particles CsTeMoO6 under Visible Light

The antimicrobial activity of submicron particles of new photocatalytic active complex metal oxide CsTeMoO6 against bacteria Escherichia coli and Staphylococcus aureus and fungi Aspergillus niger and Penicillium chrysogenum (spores and vegetative mycelium) was studied. It has been established that CsTeMoO6 has the antimicrobial activity in both under dark and visible light conditions in relation to all test cultures of microorganisms. The most inhibitory effect of CsTeMoO6 was noted for E. coli. The light enhanced the antimicrobial effect of the test compound against all cultures of bacteria and fungi, which is associated with the presence of photocatalytic activity of CsTeMoO6. The antifungal activity of CsTeMoO6 increased against spores and vegetative mycelium of fungi under light condition, and this effect increased with an increasing duration of time exposure. The different degree of survival rate of the studied microorganisms in the presence of this compound (under both dark and light) may be associated with the physiological and biochemical characteristics of the used microorganisms, including different mechanisms of resistance against complex metal oxide and reactive oxygen species.

Antifungal activity and mechanism of Litsea cubeba (Lour.) Persoon essential oil against the waxberry spoilage fungi Penicillium oxalicum and its potential application

Litsea cubeba essential oil (LCEO) is a broad-spectrum bacteriostatic substance produced from the fruit of the Litsea tree that has been used for the treatment of various diseases in China for thousands of years. Here, the antifungal activities of LCEO against 10 different fungi (Naganishia diffluens, Fusarium sacchari, Cladosporium tenuissimum, Fusarium proliferatum, Fusarium verticillioides, Fusarium subglutinans, Mucor racemosus, Penicillium oxalicum, Penicillium chrysogenum, and Aspergillus niger) that cause rot to waxberries were assessed. The chemical components of LCEO and its modes of action against P. oxalicum were investigated. Citral (32.62 %) was characterized as the main component of LCEO by gas chromatography–mass spectrometry. LCEO exhibited excellent antifungal activities against all 10 fungi. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration of LCEO against P. oxalicum were 2.24 and 4.48 g/L, respectively. Furthermore, LCEO (MIC) compromised membrane permeability and integrity, caused leakage of the cell components, and increased production of malondialdehyde and reactive oxygen species. Scanning electron microscopy and transmission electron microscopy indicated that the morphology and ultrastructure of the LCEO-treated hyphal cell membrane and organelles were severely damaged. Meanwhile, LCEO increased the shelf life of waxberries from 1–2 to 5–6 d. LCEO is a potential ecologically friendly alternative to commercial fungicides to inhibit postharvest fungal contamination of waxberries during shipment and storage.

Extracellular Zn Detoxication by <i>Penicillium chrysogenum</i> and <i>Aspergillus niger</i>

Microfungi are promising objects for bioremediation due to their ability to convert metals into forms that are less mobile and accessible to organisms. The study showed that the fungi Penicillium chrysogenum and Aspergillus niger have physiological mechanisms of extracellular Zn detoxification at its initial concentration of 250 µmol – 2 mmol in the medium. At concentrations of 250–500 µmol Zn promotes the accumulation of biomass and abundant sporulation of A. niger and Penicillium chrysogenum, and at concentrations of 1–2 mmol inhibits the growth of fungi. Extracellular Zn detoxification in Aspergillus niger culture occurs by the formation of dihydrate zinc oxalate katsarosite, due to the active biosynthesis of oxalic acid in A. niger. The main mechanism of zinc detoxification in Penicillium chrysogenum culture was the formation of zinc phosphate hopeite. The formation of zinc phosphate hopeite under the action of the fungus was established for the first time. The key factors that determine the direction of the processes of formation of extracellular mineral phases are the amounts of EPS and oxalic acid produced by fungi, as well as changes in the pH of the medium during the growth of cultures.

Mining and identification of a biosynthetic gene cluster producing xanthocillin analogues from Penicillium chrysogenum MT-40, an endophytic fungus of Huperzia serrata

Xanthocillin is a unique natural product with an isonitrile group and shows remarkable antibacterial activity. In this study, the genome of an endophytic fungus Penicillium chrysogenum MT-40 isolated from Huperzia serrata was sequenced, and the gene clusters with the potential to synthesize xanthocillin analogues were mined by local BLAST and various bioinformatics analysis tools. As a result, a biosynthetic gene cluster (named for) responsible for the biosynthesis of xanthocillin analogues was identified by further heterologous expression of the key genes in Aspergillus oryzae NSAR1. Specifically, the ForB catalyzes the synthesis of 2-formamido-3-(4-hydroxyphenyl) acrylic acid, and the ForG catalyzes the dimerization of 2-formamido-3-(4-hydroxyphenyl) acrylic acid to produce the xanthocillin analogue N, N'-(1, 4-bis (4-hydroxyphenyl) buta-1, 3-diene-2, 3-diyl) diformamide. The results reported here provide a reference for further discovery of xanthocillin analogues from fungi.

Secondary metabolites from the marine-derived fungus Penicillium chrysogenum Y20-2, and their pro-angiogenic activity.

A systematic chemical study of the secondary metabolites of the marine fungus, Penicillium chrysogenum (No. Y20-2), led to the isolation of 21 compounds, one of which is new (compound 3). The structures of the 21 compounds were determined by conducting extensive analysis of thespectroscopic data. The pro-angiogenic activity of eachcompound was evaluated using a zebrafish model. Theresultsshowed that compounds 7, 9, 16, and 17 had stronganddose-dependent pro-angiogenic effects, with compound 16 demonstrating the strongest pro-angiogenic activity, compounds 6, 12, 14, and 18 showing moderate activity, and compounds 8, 13, and 19 exhibiting relatively weak activity.

Epigenetic Induction of Secondary Metabolites Production in Endophytic Fungi Penicillium chrysogenum and GC-MS Analysis of Crude Metabolites with Anti-HIV-1 Activity.

The continuous burden of human immunodeficiency virus-1 in Sub-Saharan Africa, coupled with the inability of antiretroviral agents to eradicate HIV-1 from viral reservoirs, the potential risks of drug resistance development, and the development of adverse effects, emphasizes the need to develop a new class of HIV-1 inhibitors. Here, we cultivated four endophytic fungal isolates from a medicinal plant, Albizia adianthifolia with the addition of small epigenetic modifiers, sodium butyrate, and valproic acid, to induce the expression of biosynthetic gene clusters encoding active secondary metabolites with probable anti-HIV activities. We identified a non-toxic crude extract of the endophytic fungus Penicillium chrysogenum treated with sodium butyrate to possess significantly greater anti-HIV activity than the untreated extracts. Penicillium chrysogenum P03MB2 showed anti-HIV activity with an IC50 of 0.6024 µg/mL compared to untreated fungal crude extract (IC50 5.053 µg/mL) when treated with sodium butyrate. The profile of secondary metabolite compounds from the bioactive, partially purified extracts were identified by gas chromatography-mass spectrometry (GC-MS), and more bioactive compounds were detected in treated P. chrysogenum P03MB2 fractions than in untreated fractions. Pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro (13.64%), cyclotrisiloxane, hexamethyl (8.18%), cyclotetrasiloxane, octamethyl (7.23%), cyclopentasiloxane, decamethyl (6.36%), quinoline, 1,2-dihydro-2,24-trimethyl (5.45%), propanenitrile (4.55%), deca-6,9-diene (4.55%), dibutyl phthalate (4.55%), and silane[1,1-dimethyl-2-propenyl)oxy]dimethyl (2.73%) were the most abundant compounds. These results indicate that treatment of endophytic fungi with small epigenetic modifiers enhances the secretion of secondary metabolites with stronger anti-HIV-1 properties, acknowledging the feasibility of epigenetic modification as an innovative approach for the discovery of cryptic fungal metabolites which can be developed into therapeutic compounds.

A comprehensive review on the medicinally valuable endosymbiotic fungi Penicillium chrysogenum

Recently, it has been shown that metabolites derived from endosymbiotic fungi attracted high attention, since plenty of them have promising pharmaceutical applications. The variation of metabolic pathways in fungi is considered an optimistic source for lead compounds. Among these classes are terpenoids, alkaloids, polyketides, and steroids, which have proved several pharmacological activities, including antitumor, antimicrobial, anti-inflammatory, and antiviral actions. This review concludes the major isolated compounds from different strains of Penicillium chrysogenum during the period 2013–2023, together with their reported pharmacological activities. From literature surveys, 277 compounds have been identified from P. chrysogenum, which has been isolated as an endosymbiotic fungus from different host organisms, with specific attention paid to those showing marked biological activities that could be useful in the pharmaceutical industry in the future. This review represents documentation for a valuable reference for promising pharmaceutical applications or further needed studies on P. chrysogenum.

Secondary metabolites from marine derived fungus Penicillium chrysogenum Y19-1 with proangiogenic and antithrombotic activities

Investigation of the ethyl acetate extract from the marine derived fungus Penicillium chrysogenum Y19-1 led to the isolation and identification of nine compounds, including ethyl formyltyrosinate (1), ergosterol peroxide (2), ergosterol (3), cerebroside A (4), conidiogenone C (5), dihydroresorcylide (6), 7-hydroxydihydroresorcylide (7), N-(2-hydroxypropanoyl)-2-aminobenzoic acid amide (8), and 4-methyl-5,6-dihydro-2H-pyran-2-one (9). Their chemical structures were determined by NMR analysis, ESIMS experiment and comparison with the reported data in the literature. Among them, compound 1 was identified as a natural product for the first time. All compounds were evaluated for antithrombotic and proangiogenic activities. Compounds 1, 4 and 5 exhibited antithrombotic activities, while compounds 1, 2, 8 and 9 showed proangiogenic activities. Meanwhile, the chemotaxonomic significance of these isolated compounds was also discussed.

Biotechnological Fungal Platforms for the Production of Biosynthetic Cannabinoids.

Cannabinoids are bioactive meroterpenoids comprising prenylated polyketide molecules that can modulate a wide range of physiological processes. Cannabinoids have been shown to possess various medical/therapeutic effects, such as anti-convulsive, anti-anxiety, anti-psychotic, antinausea, and anti-microbial properties. The increasing interest in their beneficial effects and application as clinically useful drugs has promoted the development of heterologous biosynthetic platforms for the industrial production of these compounds. This approach can help circumvent the drawbacks associated with extraction from naturally occurring plants or chemical synthesis. In this review, we provide an overview of the fungal platforms developed by genetic engineering for the biosynthetic production of cannabinoids. Different yeast species, such as Komagataella phaffii (formerly P. pastoris) and Saccharomyces cerevisiae, have been genetically modified to include the cannabinoid biosynthetic pathway and to improve metabolic fluxes in order to increase cannabinoid titers. In addition, we engineered the filamentous fungus Penicillium chrysogenum for the first time as a host microorganism for the production of Δ9-tetrahydrocannabinolic acid from intermediates (cannabigerolic acid and olivetolic acid), thereby showing the potential of filamentous fungi as alternative platforms for cannabinoid biosynthesis upon optimization.

Synthesis and Antimicrobial Activity Evaluation of Homodrimane Sesquiterpenoids with a Benzimidazole Unit.

Herein we report a feasible study concerning the synthesis and the in vitro antimicrobial activity of some new homodrimane sesquiterpenoids with a benzimidazole unit. Based on some homodrimane carboxylic acids, on their acyl chlorides and intermediate monoamides, a series of seven N-homodrimenoyl-2-amino-1,3-benzimidazoles and 2-homodrimenyl-1,3-benzimidazoles was synthesized. The syntheses involved the decarboxylative cyclization and condensation of the said acids or acyl chlorides with o-phenylendiamine and 2-aminobenzimidazole, as well as the p-TsOH-mediated cyclodehydration of the said monoacylamides. The structures of the synthesized compounds have been fully confirmed, including by the X-ray diffraction. Their biological activities were evaluated on five species of fungi (Aspergillus niger, Fusarium solani, Penicillium chrysogenum, P. frequentans, and Alternaria alternata) and two strains of bacteria (Bacillus sp. and Pseudomonas aeruginosa). Compounds 7 and 20 showed higher antifungal (MIC = 0.064 and 0.05 μg/mL) and antibacterial (MIC = 0.05 and 0.032 μg/mL) activities compared to those of the standards: caspofungin (MIC = 0.32 μg/mL) and kanamycin (MIC = 2.0 μg/mL), and compounds 4, 10, 14, and 19 had moderate activities.

Discovering the chemical profile, antimicrobial and antibiofilm potentials of the endophytic fungus Penicillium chrysogenum isolated from Artemisia judaica L. assisted with docking studies

The continuous impedance of Pseudomonas aeruginosa to traditional antibacterial drugs due to biofilm formation resulted in a growing necessity to develop effective antibiofilm formation treatments. Thus, such a study was conducted to search for the natural metabolites from the endophytic Penicillium chrysoginum AJEF2 as a source of prospective antibiofilm-forming agents. Generally, the OSMAC (one strain many compounds) approach was undertaken to ascertain that the modified potato dextrose broth (MPDB) culture displayed substantial antibacterial potential towards various human pathogenic microorganisms (MICs = 125–500 µg/mL) and exhibited a remarkable percentage of biofilm inhibition against Pseudomonas aeruginosa clinical isolates by 92.3%. LC-ESI-HRMS analysis of such extract annotated seventeen metabolites that were screened for their inhibitory biofilm formation based on molecular docking simulation on LasR protein-specific quorum sensing. Interestingly, gladiolic acid, 8‑hydroxy-6-methylxanthone-1-carboxylic acid methyl ester, cyclo(L-tryptophanyl- l -tryptophanyl), and citreoanthrasteroid A, showed acceptable interaction energies and formed significant interactions inside the LasR active site. Those results highlight endophytic Penicillium chrysoginum AJEF2 as a potential source for antibiofilm compounds. • Antimicrobial and anti-biofilm forming activities were displayed by the endophytic P. chrysogenum AJEF2 strain isolated from Artemisia judica . • LC HRMS analysis characterized structurally assorted metabolites, mainly phenolics, benzopyran, benzofuran, coumarins, polyketide, dipeptide, meroterpene, and steroids. • Molecular docking simulation on LasR protein-specific quorum sensing was done. • Gladiolic acid, 8‑hydroxy-6-methylxanthone-1-carboxylic acid methyl ester, cyclo(L-tryptophanyl- l -tryptophanyl) and citreoanthrasteroid A, were the most likely to inhibit the biofilm formation based on molecular docking studies.

Production of Nematicidal Pinosylvin Stilbenes in Cell Suspension Cultures of Pinus koraiensis by Fungal Elicitation.

Pinosylvin stilbenes are natural phenolic compounds found in the Pinaceae family and act as phytoalexins. Some pinosylvin stilbenes have strong nematicidal activity against pine wood nematodes (PWNs: Bursaphelenchus xylophilus). Here, we established the efficient production of two pinosylvin stilbenes, dihydropinosylvin monomethylether (DPME) and pinosylvin monomethylether (PME), by cell suspension culture of Pinus koraiensis after fungal elicitation. DPME and PME were found in small amounts (less than 40 µg/g DW) in the stem bark and leaves of P. koraiensis plants. Cell suspension cultures were established from the cultures of calli derived from mature zygotic embryos of P. koraiensis in 1/2 Litvay medium containing 2.2 μM 2,4-D and 2.2 μM BA. Two types of fungal elicitors, fungal cell extract (CE) and fungal medium filtrate (MF), were prepared from three species of fungi (Penicillium chrysogenum, P. pinophilum, and P. roquefortii). CE and MF treatments strongly stimulated the production of PME and DPME in cultured cells. The production of PME in suspension cells of P. chrysogenum, P. pinophilum, and P. roquefortii MF treatments after 3 days was 5734 µg/g DW, 4051 µg/g DW, and 6724 µg/g DW, respectively. Pinosylvin synthase (PkSTS) and pinosylvin O-methyltransferase (PkPMT) are key genes in DPME and PME biosynthesis. qPCR analysis revealed that the expression of the PkSTS and PkPMT in cultured cells was highly enhanced after fungal elicitor treatment. The cell extracts after MF treatment resulted in 92.5 ± 7.8% immobilization of the adult PWNs and 63.7 ± 3.5% immobilization of the juvenile PWNs within 24 h. However, control cell extracts without MF treatment showed 11.3 ± 1.4% nematicidal activity against adult PWNs. Our results suggest that pinosylvin stilbenes can be produced from the cell culture of P. koraiensis after fungal elicitor treatment and can be used as nematicidal compounds against PWNs.

Pseudomonas sp., Strain L5B5: A Genomic and Transcriptomic Insight into an Airborne Mine Bacterium

Mines, like other subterranean environments, have ecological conditions which allow the thriving of microorganisms. Prokaryotes and fungi are common inhabitants of mines, developing a metabolism suitable for growing in such inhospitable environments. The mine of Lousal, Portugal, is an interesting site for the study of microorganisms present in their galleries. Aerobiological studies resulted in the isolation of a Pseudomonas sp., strain L5B5, closely related to the opportunistic fish pathogen P. piscis MC042T, and to the soil bacteria P. protegens CHA0T, P. protegens Cab57, and P. protegens Pf-5. Strain L5B5 was able to inhibit the growth of the pathogenic bacteria Bacillus cereus, Staphylococcus aureus, and Acinetobacter baumanii, as well as the cave fungi Aspergillus versicolor, Penicillium chrysogenum, Cladosporium cladosporioides, Fusarium solani, and Ochroconis lascauxensis. In silico analyses based on de novo genome hybrid assembly and RNA-Seq, performing seven conditions based on culture and phases of growth resulted in the prediction and detection of genetic mechanisms involved in secondary metabolites, with the presence of a possible new gene cluster transcribed under the tested conditions, as well as feasible virulence factors and antimicrobial resistance mechanisms.

Terrien, a metabolite made by Aspergillus terreus, has activity against Cryptococcus neoformans.

Antimicrobial compounds, including antibiotics, have been a cornerstone of modern medicine being able to both treat infections and prevent infections in at-risk people, including those who are immune-compromised and those undergoing routine surgical procedures. Their intense use, including in people, animals, and plants, has led to an increase in the incidence of resistant bacteria and fungi, resulting in a desperate need for novel antimicrobial compounds with new mechanisms of action. Many antimicrobial compounds in current use originate from microbial sources, such as penicillin from the fungus Penicillium chrysogenum (renamed by some as P. rubens). Through a collaboration with Aotearoa New Zealand Crown Research Institute Manaaki Whenua–Landcare Research we have access to a collection of thousands of fungal cultures known as the International Collection of Microorganisms from Plants (ICMP). The ICMP contains both known and novel species which have not been extensively tested for their antimicrobial activity. Initial screening of ICMP isolates for activity against Escherichia coli and Staphylococcus aureus directed our interest towards ICMP 477, an isolate of the soil-inhabiting fungus, Aspergillus terreus. In our investigation of the secondary metabolites of A. terreus, through extraction, fractionation, and purification, we isolated nine known natural products. We evaluated the biological activity of selected compounds against various bacteria and fungi and discovered that terrein (1) has potent activity against the important human pathogen Cryptococcus neoformans.

Preliminary Microbiological Tests of S-Carvone and Geraniol and Selected Derivatives of These Compounds That May Be Formed in the Processes of Isomerization and Oxidation.

This work presents a literature review on the biological activity of S-carvone, geraniol and derivatives of these compounds, which are formed in the process of isomerization (during the process of geraniol isomerization, oxidation products of this compound are also obtained). Moreover, this work presents preliminary microbiological tests of creams with the addition of these biologically active compounds: S-carvone, geraniol, carvacrol (an S-carvone isomerization product), nerol (a geraniol isomerization product), linalool (a geraniol isomerization product) and citral (a geraniol oxidation product). Because the post-reaction mixture obtained after the S-carvone isomerization has a relatively simple composition, it was also added to creams and tested without isolating pure compounds. This may be a cheaper alternative to creams prepared with the addition of pure compounds. The mixture obtained after the geraniol isomerization process has a very complex composition; therefore, only compounds with the lowest molecular weight and are easily commercially available were selected for studies. The content of the tested compounds in the creams ranged from 0.5 to 3 wet%. The following microorganisms were selected for microbiological tests: the Gram-negative bacterium Escherichia coli K12, the Gram-positive bacterium Staphylococcus epidermidis, and the fungi Candida albicans, Trichophyton rubrum, Aspergillus niger, and Penicillium chrysogenum. A content of 3% carvacrol, nerol, geraniol and citral inhibited the growth of E. coli, and attenuated the growth of C. albicans and T. rubrum. On the other hand, 3% carvacrol and citral only poorly attenuated the growth of the mould fungi P. chrysogenum and A. niger.

S5.3b Fungal spores: Initiators of colonization and infection

S5.3 Cellular pleomorphism and fungal virulence, September 22, 2022, 3:00 PM - 4:30 PMFungi produce asexual and sexual spores for reproduction and distribution, which can be both in space and time. Distribution in space occurs, by air movement, but also, by water or other vectors such as living organisms. Filamentous fungi from the division Ascomycota that belong to the order Eurotiales produce asexual spores called conidia. Conidia are moderately stress-tolerant cells and are able to survive unfavorable conditions such as thermal stress, dehydration, osmotic pressure, oxidative stress, variations in pH, and UV. For example, conidia of the fungus Penicillium chrysogenum are isolated worldwide and must be regarded as cosmopolitan. In many cases, conidia might ‘land’ closely to the location of production, but still many spores making into the higher air layers. There is indirect evidence that spores may be able to travel large distances through the air. For example, Aspergillus sydowii conidia have been suggested to travel over thousands of kilometers from the Sahara Desert to the Caribbean reefs. Distribution in time is occurring as stress-resistant cells remain dormant at one location for an extended period, awaiting conditions that are more favorable for growth. Some ascospores (sexual spores) are extremely stress-resistant and dormant for very long periods. Other species show extended dormancy in a dried state. As microbial species are inherently variable, stress resistance varies between strains from the same species. For example, conidial heat resistance (D60) of various strains of the fungus Paecilomyces variotii ranged between 3.5 to 27.6 min. This intraspecific variation could have profound consequences on diagnostics, virulence, and antifungal treatment in clinical settings. For conidial germination in most filamentous fungi, the presence of nutrients such as inorganic salts, sugars, and amino acids is required. The swelling phase of conidia is also called isotropic growth. Swollen conidia direct the growth to one side of the cell to grow in a polarized fashion, which leads to the formation of a germ tube (polarized growth). There is a notable drop in stress resistance during isotropic and polarized growth and genes expressed during these stages might represent novel targets for fungal infection.

<em>Ocimum campechianum</em> essential oil: chemical composition and antifungal activity against filamentous fungi

Ocimum campechianum (OC), an aromatic and medicinal plant from the Amazon region, is rich in essential oils with antimicrobial potential. This study aimed to analyze the quality, toxicity, and antifungal action of Ocimum campechianum essential oil(OCEO). The plant species were collected in the city of São Luís-MA (Brazil). The essential oil (EO) was extracted by hydrodistillation in a Clevenger apparatus, and the physical-chemical parameters were analyzed according to the Brazilian Pharmacopoeia norms. The essential oil constituents were identified by gas chromatography-mass spectrometry (GC-MS). Toxicity was evaluated against brine shrimp (Artemia salina Leach). The antifungal activity was evaluated by the method of disk diffusion and microdilution in broth against ATCC strains of filamentous fungi Aspergillus Niger (ATCC 6275), Colletotrichum gloeosporioides (ATCC 96723), and Penicillium chrysogenum (ATCC 10106. The essential oil showed a slightly yellowish color, intense clove aroma, a density of 1.0 ± 0.0 g/mL, a refractive index of 1.52 ± 0.00, solubility in ethanol (1:2), and a yield of 1.40%. The chromatographic profile showed 36 volatile compounds, the majority being eugenol (49.18%), followed by β- caryophyllene (17.26%), elixene (9.46%), methyl eugenol (7.65%), and eucalyptol (2,55%). It presented LC 50 = 955 μg / mL against Artemia salina. The fungi induced growth inhibition zones (14.90 to 17.85 mm). The fungus P. chrysogenum was the most susceptible (MIC 220 μg/ml) compared to the fungi A. niger (MIC 250 μg/mL) and C. gloeosporioides (MIC 270 μg/mL). The minimum fungicide concentration (MFC) was sufficient to inhibit the growth of P. chrysogenum at 380 μg/mL, A. niger at 400.25 μg/mL, and C. gloeosporioides at 416.66 μg/mL. The OCEO showed good quality, low toxicity, and fungicidal action against the filamentous fungi analyzed, suggesting its application as a promising natural antifungal, mainly in combating diseases in post-harvest crops.

Potential Antimicrobial and Antibiofilm Properties of Copper Oxide Nanoparticles: Time-Kill Kinetic Essay and Ultrastructure of Pathogenic Bacterial Cells

Mycosynthesis of nanoparticle (NP) production is a potential ecofriendly technology for large scale production. In the present study, copper oxide nanoparticles (CuONPs) have been synthesized from the live cell filtrate of the fungus Penicillium chrysogenum. The created CuONPs were characterized via several techniques, namely Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX). Furthermore, the biosynthesized CuONPs were performed against biofilm forming Klebsiella oxytoca ATCC 51,983, Escherichia coli ATCC 35,218, Staphylococcus aureus ATCC 25,923, and Bacillus cereus ATCC 11,778. The anti-bacterial activity result was shown with the zone of inhibition determined to be 14 ± 0.31 mm, 16 ± 0.53 mm, 11 ± 0.57 mm, and 10 ± 0.57 mm respectively. Klebsiella oxytoca and Escherichia coli were more susceptible to CuONPs with minimal inhibitory concentration (MIC) values 6.25 and 3.12 µg/mL, respectively, while for Staphylococcus aureus and Bacillus cereus, MIC value was 12.5 and 25 μg/mL, respectively. The minimum biofilm inhibition concentration (MBIC) result was more evident, that the CuONPs have excellent anti-biofilm activity at sub-MIC levels reducing biofilm formation by 49% and 59% against Klebsiella oxytoca and Escherichia coli, while the results indicated that the MBIC of CuONPs on Bacillus cereus and Staphylococcus aureus was higher than 200 μg/mL and 256 μg/mL, respectively, suggesting that these CuONPs could not inhibit mature formatted biofilm of Bacillus cereus and Staphylococcus aureus in vitro. Overall, all the results were clearly confirmed that the CuONPs have excellent anti-biofilm ability against Klebsiella oxytoca and Escherichia coli. The prepared CuONPs offer a smart approach for biomedical therapy of resistant microorganisms because of its promoted antimicrobial action, but only for specified purposes.