Antifungal Substances Research Articles

The inhibitory effect of volatile organic compounds produced by Bacillus subtilis CL2 on pathogenic fungi of wolfberry.

Bacillus subtilis strain CL2 is antagonistic to wolfberry postharvest pathogenic fungi. In this study, we isolated and screened this strain for in vitro experiments. The result of the two-sealed-base-plates method revealed that volatile organic compounds (VOCs) emitted from the strain CL2 inhibited the hyphal growth of four pathogenic fungi Mucor circinelloides LB1, Fusarium arcuatisporum LB5, Alternaria iridiaustralis LB7, and Colletotrichum fioriniae LB8. After exposure to VOCs for 5 days, the hyphal growth of the pathogen C. fioriniae LB8 was inhibited by 73%. Scanning electron microscopy revealed that the VOCs produced by B. subtilis CL2 caused the mycelium morphology of the pathogenic fungi to deform, twist, fold, and shrink. In the in vivo experiments, we noticed that VOCs could significantly reduce the weight loss rate of wolfberry fruits caused by the pathogenic fungus M. circinelloides LB1 and that the decay incidence rate were caused by the pathogenic fungi F. arcuatisporum LB5, A. iridiaustralis LB7, and C. fioriniae LB8. On the basis of the headspace-gas chromatography-ion mobility spectrometry analysis, seven VOCs produced by strain CL2 were identified. Among them, 2,3-butanedione and 3-methylbutyric acid are the main antifungal active substances. This study investigated the antifungal properties of VOCs produced by the strain CL2 on postharvest pathogenic fungi isolated from wolfberry fruits both in vivo and in vitro, thereby providing the theoretical basis for its future applications.

Pharmacokinetics interaction of calcium on the treatment of sputum positive pulmonary tuberculosis patients

Tuberculosis (TB) in children is a neglected aspect of the TB epidemic despite it constituting 20% or more of all TB cases in many countries with high TB incidence. Tuberculosis constitutes a serious global health problem with nearly 10 million new cases of tuberculosis (2011) and 1.4 million deaths every year. In pharmacokinetic studies, co-administration of various inhibitors of this enzyme (e.g., erythromycin, antifungal substances, protease inhibitors, and grapefruit juice) raised plasma phosphate concentrations by up to 500%. Materials and Methods: The study was conducted in Chennai tuberculosis hospital from January 2012 through July 2015 in seven target groups, with consecutive recruitment. The first group consisted of otherwise deselected patients who are presented with suspected tuberculosis to the tuberculosis hospital in Chennai. Blood samples were collected from the subjects of tuberculosis Hospital at Chennai. To non-treatment and treatment variations, fasting blood samples were collected from 8 AM - 9 AM. Experiments were carried out as soon as possible. Whenever there was a delay in experiments, samples were stored at -10° to -15°C for a maximum of 1 day. Blood samples thus collected using standard sampling techniques were centrifuged to get the serum that was analysed phosphorus levels by Phosphomolybdate method. The study protocol was approved by the Institutional ethics committee and was carried out in accordance with the principle of the declaration of Helsinki. Results: In the study, mean serum phosphorus level in newly diagnosed patients was 13 ± 3.30 mg/dl, after first month treatment to sixth month treatment the level was 13 ± 3.60mg/dl, 11 ± 3.30 mg/dl, 10.50 ± 3.30 mg/dl, 11 ± 3.30 mg/dl, 11.20 ± 2.80 mg/dl and 10.20 ± 2.80 mg/dl respectively. Six-month treatment 20 patients were get the hyperphosphatemia for include female 9 patients. One study suggests that Estrogen may act directly to suppress sodium-dependent phosphate absorption in the renal proximal tubules inducing phosphaturia and decreased serum phosphate; women who are post-menopausal and Estrogen deficient would be at increased risk for hyperphosphatemia Low serum phosphate levels are associated with reduced cardiac output and also with risk for arrhythmia. Conclusion: Our findings offer the possibility that early intervention will help achieve calcium and phosphorus conversion and ultimately a successful treatment outcome. In order for us to update guidelines and optimize patient care, some gaps in the evidence base need to be addressed. Although available data demonstrate the association between hyperphosphatemia and increased risk of mortality, it remains a challenge in the clinic to achieve and maintain recommended serum phosphorus concentrations. Keywords: Hyperphosphatemia, Phosphomolybdate Method, Pulmonary Tuberculosis

Periodontal effects of two innovative oral rinsing substances in oncologic patients.

Chemotherapy often presents side effects, including oral adverse effects that may interfere with the completion of the oncology treatment, threatening the outcome of the treatment and significantly affecting the quality of life of the patient. The aim of the present study was to evaluate two antiseptic, antimicrobial and antifungal substances that may be used in order to achieve improved oral hygiene and to lower the prevalence of side effects during chemotherapy. Patients were randomly divided into three groups: Placebo, oral rinse with cetrimide and mouth coating with a pharmacy-made compound (nystatin, neomycin and metronidazole). Their oral hygiene and periodontal parameters were determined at baseline and 14 days of use. It was revealed that the most effective clinical results were achieved in the group that used cetrimide mouth rinse that highlighted the best improvements of parameter values, whereas the control and coating-using group did not obtain statistically significant improvements. Cetrimide oral rinse was demonstrated to be an efficient adjunct method in achieving better oral hygiene and improved periodontal parameters in chemotherapy patients. The present study offers an alternative to the commonly used compounds that may present unwanted side effects in patients during chemotherapy, it promotes the importance of good oral hygiene in the prevention of chemotherapy-induced oral adverse effects and improves the quality of life of the patient.

Morphological and molecular characterisation of Streptomyces spp. which suppress pathogenic fungi

Streptomyces species are aerobes and chemoorganotrophic bacteria. These microorganisms produce a wide range of industrially significant compounds, specifically antibiotics and anti fungal substances. The objective of this study was to characterise soil-borne Streptomyces isolates using morphological and molecular traits in order to identify them to species level, and leverage from their potential to suppress the growth of Aspergillus flavus, Fusarium oxysporum and Penicillium italicum. Twenty-seven soil-borne putative Streptomyces, which elicited comprehensive antimicrobial activity against Aspergillus flavus, Fusarium oxysporum and Penicillium italicum, in a previous study, were evaluated. On the basis of morphology, the bacteria resembled the genus Streptomyces. Initially, colonies phenotypically appeared to have a relatively smooth surface but as growth progressed the bacteria developed a weft of aerial mycelium granular, powdery or velvety in appearance. Bacteria produced a wide variety of pigments which in turn were responsible for the colour of the vegetative and aerial mycelia, colour ranged from white to cream or buff shades and yellow to orange or brown. Microscopic analyses and morphological characteristics generated sub-groups of the isolates and clustered them according to their similarities. One bacterial strain was randomly selected from each cluster and investigated using molecular characteristics. Partial 16S rDNAs from the selected representative isolates from each subgroup, were sequenced and phylogenetic analysis performed. The 16S rDNA sequences of the isolates indicated that they were related to Streptomyces species: S. bungoensis, S. thermocarboxydus, S. corchorusii and S. lasaliensis, that are known secondary metabolite producers possessing antimicrobial activity against plant pathogens.

Formulation of an Ointment from Hydroethanolic Extract of Terminalia ivorensis and Therapeutic Trial on Volunteers with Moths

This study was conducted to make a contribution in the treatment of dermatosis, particularly moths. Ointments of different concentrations made from the hydroethanolic extract of Terminalia ivorensis and shea butter were used. The best results were obtained with the following concentrations: C4: 0.01 g/mL; C5: 0.0125 g/mL; C6: 0.015 g/mL and C10: 0.025 g/mL for trichophytic clipping moth on eleven (11) selected persons with ringworm and C9: 0.0225 g/mL for microsporic clipping moth on one (1) person. The present study really provides the scientific basis for the use of this plant in the traditional treatment of diseases and may help to discover new chemical classes of antifungal substances that could serve as selective agents for infectious disease chemotherapy.

Conventional therapy and new antifungal drugs against Malassezia infections.

Malassezia yeasts are commensal microorganisms occurring on the skin of humans and animals causing dermatological disorders or systemic infections in severely immunocompromised hosts. Despite attempts to control such yeast infections with topical and systemic antifungals, recurrence of clinical signs of skin infections as well as treatment failure in preventing or treating Malassezia furfur fungemia have been reported most likely due to wrong management of these infections (e.g., due to early termination of treatment) or due to the occurrence of resistant phenomena. Standardized methods for in vitro antifungal susceptibility tests of these yeasts are still lacking, thus resulting in variable susceptibility profiles to azoles among Malassezia spp. and a lack of clinical breakpoints. The inherent limitations to the current pharmacological treatments for Malassezia infections both in humans and animals, stimulated the interest of the scientific community to discover new, effective antifungal drugs or substances to treat these infections. In this review, data about the in vivo and in vitro antifungal activity of the most commonly employed drugs (i.e., azoles, polyenes, allylamines, and echinocandins) against Malassezia yeasts, with a focus on human bloodstream infections, are summarized and their clinical implications are discussed. In addition, the usefulness of alternative compounds is discussed.

Utilization of straw-based phenolic acids as a biofugicide for a green agricultural production

Phenolic compounds inhibit phytopathogenic fungal infections effectively. In this study, the antifungal effects of rice straw-derived phenolic acids (PAs) against Fusarium oxysporum were investigated. PAs can inhibit hyphal growth and spore germination, and p-coumaric acid (CA) is the main antifungal substance in PAs. PAs could induce the formation of hydrogen peroxide and increase the relative conductivity and extracellular K+ concentration. Observations using Scanning Electron Microscopy, Laser Scanning Confocal Microscopy and Transmission Electron Microscopy revealed that PAs could damage membrane permeability, which caused cytoplasm leakage. This phenomenon was verified by conductivity and the release of extracellular K+. The chlorophyll fluorescence maps of tomato leaves suggested that F.oxysporum damaged the tomato' photosynthetic system and that PAs reduced the area infected, thereby alleviating the damage. Moreover, PAs could decrease the disease incidence of tomato fruit. The results confirmed the feasibility of using PAs as a biofungicide and provide a way to increase the value of rice straw.

Application of lactic acid bacteria producing antifungal substance and carboxylesterase on whole crop rice silage with different dry matter.

ObjectiveThis study was conducted to investigate effects of antifungal substance and carboxylesterase-producing inoculant on fermentation indices and rumen degradation kinetics of whole crop rice (WCR) silage ensiled at different dry matter (DM) contents.MethodsDual-purpose inoculants, Lactobacillus brevis 5M2 and Lactobacillus buchneri 6M1, confirmed both activities of antifungal and carboxylesterase in the previous study. The WCR at mature stage was chopped, and then wilted to obtain three different DM contents consisting of 35.4%, 43.6%, and 51.5%. All WCR forages were applied distilled water (CON) or mixed inoculants with 1:1 ratio at 1×105 colony forming unit/g (INO), and ensiled into 20 L mini silo (5 kg) in quadruplicates for 108 d.ResultsThe INO silages had lower lactate (p<0.001) and butyrate (p = 0.022) with higher acetate (p<0.001) and propionate (p<0.001) than those of CON silages. Ammonia-N (p<0.001), lactate (tendency; p = 0.068), acetate (p = 0.030), and butyrate (p<0.001) concentrations of INO silages decreased linearly with increasing DM content of WCR forage. The INO silages presented higher lactic acid bacteria (p<0.001) with lower molds (p< 0.001) than those of CON silages. Yeasts (p = 0.042) and molds (p = 0.046) of WCR silages decreased linearly with increasing DM content of WCR forage. In the rumen, INO silages had higher the total degradable fraction (p<0.001), total volatile fatty acid (tendency; p = 0.097), and acetate (p = 0.007), but lower the fractional degradation rate (p = 0.011) and propionate (p<0.001) than those of CON silage. The total degradable fraction (p<0.001), total volatile fatty acid (p = 0.001), iso-butyrate (p = 0.036), and valerate (p = 0.008) decreased linearly with increasing DM content of WCR forage, while the lag phase (p<0.001) was increased linearly.ConclusionThis study concluded that application of dual-purpose inoculants on WCR silage confirmed antifungal and carboxylesterase activities by inhibiting mold and improving rumen digestibility, while increase of wilting times decreased organic acids production and rumen digestibility.

Atividade antifúngica do extrato etanólico de própolis vermelha contra isolados patogênicos de Candida spp.

A busca por novas substâncias antifúngicas se faz necessária, devido ao aumento de casos de infecções fúngicas nos últimos anos, associado ao aparecimento de cepas resistentes aos tratamentos convencionais e efeitos adversos observados durante as terapias farmacológicas. Dentre estas infecções, destacam-se as candidíases, como uma das mais comuns a acometerem os seres humanos. Assim, objetivou-se avaliar o potencial antifúngico do extrato etanólico de própolis vermelha contra isolados patogênicos de Candida spp. A determinação da Concentração Inibitória Mínima (CIM) foi realizada pela técnica de microdiluição, em placas de 96 cavidades, na qual verificou-se a sensibilidade de cepas de Candida spp. a concentrações do extrato de própolis numa variação de 15.000 µg/mL a 29,3 µg/mL. Os valores de CIM foram determinados pela análise visual da inibição do crescimento. Em seguida, adicionou-se cloreto de trifeniltetrazólio (TTC) para determinação da Concentração Fungicida Mínima (CFM). Todos os experimentos foram feitos em triplicata. A CIM encontrada variou de 234,4 µg/mL a 937,5 µg/mL, sendo a espécie C. albicans, a mais sensível entre as testadas. Observou-se que a CFM foi idêntica a CIM. A partir destes resultados, conclui-se que o extrato etanólico de própolis vermelha apresentou moderada atividade antifúngica sobre a maioria das cepas de Candida spp., ratificando-se seu uso tradicional quanto a suas propriedades antimicrobianas, as quais podem ser melhor exploradas através de futuros estudos pré-clínicos e clínicos.

Antifungal activity of methylxanthines based on their properties

Wood materials for construction purposes can be attacked by various wood-destroying fungi. An ideal wood-preserving substance is supposed to be environment- and health-friendly. For this reason, the effects of the most relevant and non-toxic methylxanthines, such as caffeine and its metabolites theobromine and theophylline, on fungal growth, together with their degradability related to their properties were analyzed in this study. Agar tests with four wood-destroying fungal species (Serpula lacrymans, Coniophora puteana, Gleophyllum sepiarium, and Trametes versicolor) were performed after 28 days of substance exposure. Caffeine exhibited a 100% inhibitive effect on fungal growth, contrary to theobromine, which was not effective in that respect. Theophylline exhibited variable effects on the analyzed fungi. The analysis of degradability indicated the persistence of caffeine and theobromine, but theophylline was degraded up to 34%. The relation of toxicity to chemical structure of studied methylxanthines indicated the dipole moment and lipophilicity as important parameters affecting the antifungal properties. Both caffeine and theophylline are suitable potential candidates for antifungal active substances.

The Phytochemical, Antifungal, and First Report of the Antiviral Properties of Egyptian Haplophyllum tuberculatum Extract.

In this study, ethanol whole plant extract (WPE) of Haplophyllum tuberculatum was characterized and tested for its antifungal and antiviral activities against Fusarium culmorum, Rhizoctonia solani and tobacco mosaic virus (TMV). High Performance Liquid Chromatography (HPLC) analysis showed that the main phytochemical constituents of H. tuberculatum WPE were resveratrol (5178.58 mg/kg), kaempferol (1735.23 mg/kg), myricetin (561.18 mg/kg), rutin (487.04 mg/kg), quercetin (401.04 mg/kg), and rosmarinic acid (387.33 mg/kg). By increasing H. tuberculatum WPE at concentrations of 1%, 2%, and 3%, all of the fungal isolates were suppressed compared to the two positive and negative controls. Under greenhouse conditions, WPE-treated Chenopodium amaranticolor plants strongly inhibited TMV infection and significantly reduced TMV accumulation levels when compared to non-treated plants. Moreover, the induction of systemic resistance with significant increases in the transcriptional levels of the pathogenesis-related protein-1 (PR-1), chalcone synthase (CHS), and hydroxycinnamoyl-CoA quinate transferase (HQT) genes for treated plants were noticed at 3 and 5 days post-inoculation (dpi) for both assays. To the best of our knowledge, this is the first reported observation of the antiviral activity of H. tuberculatum extract against plant viral infections. Finally, the results obtained suggest that H. tuberculatum WPE can be considered a promising source of both antifungal and antiviral substances for practical use and for developing plant-derived compounds for the effective management of plant diseases.

A novel peroxiredoxin from the antagonistic endophytic bacterium Enterobacter sp. V1 contributes to cotton resistance against Verticillium dahliae

[Aims] To reveal the molecular mechanism of endophytic bacteria in Verticillium wilt-resistant cottons and deeply understand the interaction between soil and plants. [Methods] Active tracking screening was used for the isolation of antagonistic strain. Morphological and molecular analyses were conducted to determine its phenotypic and genotypic characteristics. MALDI-TOF/TOF MS was employed to identify the antifungal substance. Functional verification was performed by gene cloning, expression, knockout and complementation. [Results] Enterobacter sp. V1 was isolated from Verticillium-wilt-resistant cotton Xinhai 15, which showed significantly antagonistic abilities against cotton verticillium wilt. A peroxiredoxin named ProV1 with virulent against V. dahliae was obtained. The gene for the peroxiredoxin ProV1 was cloned, and the nucleotide sequence showed 85.5% similarity with peroxiredoxin C (WP 096152328) reported from E. hormaeche. The purified heterologously expressed ProV1 indicated strong inhibitory activities. Moreover, the suppression of V. dahliae also decreased in proV1 mutant strain compared with wild type strain. The inhibitory activities could be partially restored by a complementation of proV1 gene in the mutant strain. [Conclusion] The results of this study reveal that a novel peroxiredoxin from an endophytic bacterial strain Enterobacter sp. V1 can serve as a virulent factor against fungi V. dahliae, which helps understanding the interaction between endyphytic bacteria and plant pathogenic fungi, and improving the biological control of cotton Verticillium wilt.

Efficacy of Phytochemical Constituents of Castor Essential oil Towards the Mucor-Mycotic Mold Cunninghamella Bertholletiae

The aim of this experiment is to study the efficacy of phytochemical constituents of Castor essential oil towards the mucor-mycotic mold Cunninghamella bertholletiae.The standard chemical analytical methods were used for the rapid study of the phytochemical constituents responsible for the antimicrobial efficacy of the procured castor essential oil. The standard antimicrobial assay technique employed to study the comparative values of the efficacy of the procured castor essential oil with that of the standard antifungal chemical agents against the clinical isolates obtained from the immune suppressed patients samples of Cunninghamella bertholletia mold mucor-mycotic infections. The best susceptibility values recorded in the standard antifungal agents against the clinical isolates of Cunninghamella bertholletiae was with Amphotericin B showing the average zone of inhibition diameter of 20.66 mm with the average MIC value of, 1.66 (µ/ml) but the antimicrobial assay results for the Castor essential oil showed better values with an average disc diffusion of 22.44mm zone of inhibition diameter with average MIC value of 1.72 µ/ml .This study has shown that the phytochemical compounds present in the Castor essential oil proves to be more an effective alternative antifungal substance towards the clinical isolates of Cunninghamella bertholletiae.

Antibacterial and antifungal activity of crude and freeze-dried bacteriocin-like inhibitory substance produced by Pediococcus pentosaceus

Pediococcus pentosaceus LBM 18 has shown potential as producer of an antibacterial and antifungal bacteriocin-like inhibitory substance (BLIS). BLIS inhibited the growth of spoilage bacteria belonging to Lactobacillus, Enterococcus and Listeria genera with higher activity than Nisaplin used as control. It gave rise to inhibition halos with diameters from 9.70 to 20.00 mm, with Lactobacillus sakei being the most sensitive strain (13.50–20.00 mm). It also effectively suppressed the growth of fungi isolated from corn grain silage for up to 25 days and impaired morphology of colonies by likely affecting fungal membranes. These results point out that P. pentosaceus BLIS may be used as a new promising alternative to conventional antibacterial and antifungal substances, with potential applications in agriculture and food industry as a natural bio-controlling agent. Moreover, cytotoxicity and cell death induction tests demonstrated cytotoxicity and toxicity of BLIS to human colon adenocarcinoma Caco-2cells but not to peripheral blood mononuclear cells, with suggests possible applications of BLIS also in medical-pharmaceutical applications.

Carbon monoxide enhances the resistance of jujube fruit against postharvest Alternaria rot

Abstract CO is a gas signal molecule involved in various physiological and metabolic regulation processes in plants. In the present study, we evaluated the effects of CO fumigation on the control of Alternaria rot in jujube fruit and explored the mechanism of action. Results showed that CO at 10 μmol L−1 significantly reduced lesion diameter in the fruit inoculated with A. alternata without showing any antifungal activity in vitro. CO treatment enhanced the activities of four representative resistance-related enzymes (phenylalanine ammonia-lyase, polyphenol oxidase, chitinase, and β-1,3-glucanase). Furthermore, CO also led to increase in the content of phenolics, flavonoids, lignin, and H2O2. These results indicate that CO induces resistance to Alternaria rot primarily by activating disease resistance-related enzymes and enhancing accumulation of antifungal substances, and that CO can be a promising elicitor of plant defense responses to resist Alternaria rot in postharvest jujube fruit.

Visualisation of penetration of topical antifungal drug substances through mycosis-infected nails by matrix-assisted laser desorption ionisation mass spectrometry imaging.

Matrix-assisted laser desorption ionisation mass spectrometry imaging (MALDI-MSI) is a mass spectrometry-based technique, which can be applied for compound-specific imaging of pharmaceuticals in tissues samples. MALDI-MSI technology is widely used to visualise penetration and distribution profile through different tissues but has never been used with nail tissue. This study used MALDI-MSI technology to visualise distribution profile and penetration into ex vivo human mycosis-infected toenails of three antifungal active ingredients amorolfine, ciclopirox and naftifine contained in topical onychomycosis nail treatment preparations, marketed as Loceryl® , Ciclopoli® and Exoderil® . Three mycosis-infected toenails were used for each treatment condition. Six and twenty-four hours after one single topical application of antifungal drugs, excess of formulation was removed, nails were cryo-sectioned at a thickness of 20μm, and MALDI matrix was deposited on each nail slice. Penetration and distribution profile of amorolfine, ciclopirox and naftifine in the nails were analysed by MALDI-MSI. All antifungal actives have been visualised in the nail by MALDI-MSI. Ciclopirox and naftifine molecules showed a highly localised distribution in the uppermost layer of the nail plate. In comparison, amorolfine diffuses through the nail plate to the deep layers already 6hours after application and keeps diffusing towards the lowest nail layers within 24hours. This study shows for the first-time distribution and penetration of certain antifungal actives into human nails using MALDI-MSI analysis. The results showed a more homogeneous distribution of amorolfine to nail and a better penetration through the infected nails than ciclopirox and naftifine.

Multicomponent Reaction of Aldehydes, Amines and Oxalacetate Analogues Leading to Biologically Attractive Pyrrole Derivatives.

Pyrrole is a very important pharmacophoric moiety. It has been widely incorporated into the skeleton of antitumor, anti-inflammatory, antibacterial, antioxidant and antifungal active substances. Access to this key heterocycle by diverse routes is particularly attractive in terms of chemistry, and also from the environmental point of view. The present minireview summarizes the reported methods for the preparation of highly substituted pyrrole derivatives based on the one-pot multicomponent reaction of aldehydes, primary amines, and oxalacetate analogues as well as their biology.

Effect of Rosemary Essential Oil and Trichoderma koningiopsis VOCs on Pathogenic Fungi Responsible for Ginseng Root-rot Disease.

Rosemary essential oil was evaluated for antifungal potentiality against six major ginseng pathogens: Sclerotinia sclerotiorum, Sclerotinia nivalis, Cylindrocarpon destructans, Alternaria panax, Botrytis cinerea, and Fusarium oxysporum. The in vitro fungicidal effects of two commonly used fungicides, namely mancozeb and fenhexamid, and the volatile organic compounds (VOCs) of Trichoderma koningiopsis T-403 on the mycelial growth were investigated. The results showed that rosemary essential oil is active against all of the pathogenic strains of ginseng root rot, whereas rosemary oil displayed high ability to inhibit the Sclerotinia spp. growth. The highest sensitivity was S. nivalis, with complete inhibition of growth at 0.1% v/v of rosemary oil, followed by Alternaria panax, which exhibited 100% inhibition at 0.3% v/v of the oil. Minimum inhibitory concentrations (MICs) of rosemary oil ranged from 0.1 % to 0.5 % (v/v). Chemical analysis using GC-MS showed the presence of thirty-two constituents within rosemary oil from R. officinals L. Camphore type is the most frequent sesquiterpene in rosemary oil composition. Mancozeb and fenhexamid showed their highest inhibition effect (45% and 30%, respectively) against A. panax. T. koningiopsis T-403 showed its highest inhibition effect (84%) against C. destructans isolate. This study may expedite the application of antifungal natural substances from rosemary and Trichoderma in the prevention and control of phytopathogenic strains in ginseng root infections.

Bacillus velezensis BM21, a potential and efficient biocontrol agent in control of corn stalk rot caused by Fusarium graminearum

The present work was conducted to screen and identify biocontrol bacteria that effectively reduce the severity of corn stalk rot (CSR) and clarify the antifungal activity of secondary metabolites. The bacterial strain (BM21) was isolated from corn rhizosphere soil that effectively reduced CSR in pot experiments. On the basis of phylogenetic reconstructions, 16S rRNA sequence analysis, and biochemical and physiological reactions, BM21 was identified as Bacillus velezensis. The strain exhibited remarkable antifungal activity against Fusarium graminearum, a pathogenic fungus that causes CSR. Extracellular antifungal substances (10%) isolated from BM21 inhibited F. graminearum mycelial growth by 79.2%, conidial germination by 84.0%, and conidial production by 78.1%. In addition, the extracellular antifungal substances caused mycelial malformation and ultra-structural changes. The extracellular antifungal substances were sensitive to heat and showed a degree of resistance to ultraviolet radiation. The optimum pH for antifungal activity was 6–8. In pot experiments, irrigation with aqueous extracts from BM21 (1.0 mL/plant) reduced CSR incidence by 72.4–77.4%. B. velezensis BM21 effectively reduced CSR incidence and showed a potential as a biocontrol agent to control CSR.

Heavy metals in livers of raptors from Eastern Poland – the importance of diet composition

Concentrations of Pb, Cd, Ni, Cr and Hg were determined in livers of six species of raptors collected in the area of Eastern Poland. Redundancy analysis (RDA) showed that elevated Hg and Cr concentrations were directly related to feeding on passerines. Raptors that specialised in seizing small mammals as a source of food revealed higher hepatic concentrations of Pb and Cd in comparison with other raptors. Unlike Cd, we found statistically significant differences in the Pb concentrations in livers of Common buzzards as compared to Sparrowhawks. In spite of the fact that both Goshawks and Sparrowhawks hunt birds, only the latter species had accumulated significantly more mercury. The high concentrations of Hg in Sparrowhawks could be related to the use of mercury in antifungal substances for seed dressing.