Antimicrobial activity of endophytic fungi from the medicinal plants Mammea americana (Calophyllaceae) and Moringa oleifera (Moringaceae) / [Actividad antimicrobiana de hongos endófitos de las plantas medicinales Mammea americana (Calophyllaceae) y Moringa oleifera (Moringaceae)].

Introduction: Infectious diseases represent one of the leading causes of death worldwide. Considering the growing global challenge of antimicrobial resistance, research into new sources of potentially effective antimicrobial agents from natural origins is of great importance for world health. Objective: To evaluate the antimicrobial activity of endophytic fungi from Mammea americana and Moringa oleifera upon Staphylococcus aureus (ATCC 29213), S. aureus (resistant strain USb003), Escherichia coli (ATCC 25922), and E. coli (resistant strain USb007). Materials and methods: We isolated endophytic fungi from the leaves, seeds, and stems of the two plants under study. We evaluated their antimicrobial activity through the formation of sensitivity haloes in dual tests in vitro, as well as in trials using crude ethanolic extracts from the endophytes. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and cytotoxicity o the substances were analyzed. Results: Three ethanolic extracts of Penicillium sp., Cladosporium (001), and Cladosporium (002) exhibited the greatest inhibition halos in sensitive and resistant strains of E. coli and S. aureus. The MIC and CBM found were statistically significant (p≤0.05) compared with the gentamicin control. Furthermore, the cytotoxicity test results of CC50>1,000 demonstrated that the endophytic fungi studied exhibit bactericidal characteristics without causing unintended damage. Conclusion: The endophytic fungi M. oleifera and M. americana represent a source of active secondary metabolites with antimicrobial and non-toxic properties. In light of these findings, further research should proceed with chemical identification of the compounds and the study of their mechanisms of action, especially given the paucity of current scientific knowledge concerning the isolation of endophytes in these plants.

Introducción. Las enfermedades infecciosas son una causa importante de muertes en el mundo. La resistencia antimicrobiana es un problema global, por lo que es conveniente la investigación de nuevas fuentes de agentes antimicrobianos de origen natural potencialmente efectivos. Objetivo. Evaluar la actividad antimicrobiana de hongos endófitos de Mammea americana y Moringa oleifera en la cepa sensible (ATCC 29213) y en la cepa resistente (USb003) de Staphylococcus aureus, así como en la cepa sensible (ATCC 25922) y la cepa resistente (USb007) de Escherichia coli. Materiales y métodos. Se aislaron 14 hongos endófitos de las hojas, semillas y tallos de las dos plantas en estudio. Se evaluó su actividad antimicrobiana mediante la formación de halos de sensibilidad por ensayo dual in vitro y pruebas con extractos etanólicos crudos provenientes de los endófitos a los que se les evaluó la concentración mínima inhibitoria (CMI), la concentración bactericida mínima (CBM) y la citotoxicidad. Resultados. Tres extractos etanólicos de Penicillium sp., Cladosporium sp. (001) y Cladosporium sp. (002) presentaron mayores halos de inhibición en cepas sensibles y resistentes de E. coli y S. aureus. La CMI y la CBM halladas fueron estadísticamente significativas (p≤0,05), comparadas con el control de gentamicina. Las pruebas de citotoxicidad (concentración citotóxica, CC50>1.000) demostraron que los hongos endófitos poseen características bactericidas y no ocasionan daño alguno. Conclusión. Se halló una fuente de metabolitos secundarios activos con propiedades antimicrobianas y no tóxicas en los hongos endófitos de M. oleifera y M. americana; estos hallazgos son importantes para continuar con la identificación química de los compuestos y el estudio de sus mecanismos de acción en estas plantas en las que el aislamiento de endófitos ha sido escaso.

Incidence, Distribution, and Pathogenicity of Fungi Causing Root Rot in Idaho Long-Term Sugar Beet Storage Piles.

Fungal rots in sugar beet roots held in long-term storage can lead to considerable sucrose loss but the incidence and distribution of fungal rots inside sugar beet piles and pathogenicity for some species is poorly understood. Thus, Idaho sugar beet held in five outdoor and two indoor piles in 2014 and 2015 were investigated. The root surface area covered by fungal growth and discolored and healthy tissue were assessed in nine 1-m2 areas per pile using a stratified random sampling design. Pathogenicity was evaluated indoors via plug inoculation in 2015 and 2016. Botrytis cinerea covered more root surface area inside indoor piles (6 to 22%) than outdoor piles (0 to 3%) (P < 0.0001). No trends were evident for the Athelia-like sp. (0 to 15%) and Penicillium-type spp. (0 to 8%). Penicillium-type isolates comprised the following species: 60% Penicillium expansum, 34% P. cellarum, 3% P. polonicum, and 3% Talaromyces rugulosus. Trace levels (<1% of root surface) of other fungi, including Cladosporium and Fusarium spp., were evident on roots and in isolations. Based on sample location in a pile, there were no trends or differences; however, two outdoor piles (OVP1 and OVP2) had more healthy tissue (90 to 96%) than other piles (28 to 80%) (P < 0.0001). When the pathogenicity tests were analyzed by species, all were significantly different from each other (P < 0.0001), except for P. polonicum and P. expansum: B. cinerea (61 mm of rot), P. polonicum (36 mm), P. expansum (35 mm), P. cellarum (28 mm), Athelia-like sp. (21 mm), T. rugulosus (0 mm; not different from check), and noninoculated check (0 mm). The OVP1 and OVP2 piles had negligible fungal growth on roots after more than 120 days of storage under ambient conditions, which indicates that acceptable storage can be achieved over this time period through covering piles with tarps and cooling with ventilation pipe.

Evaluation of disinfectants in order to eliminate fungal contamination in computer keyboards of an integrated health center in Piauí, Brazil.

This quantitative and qualitative study aimed to evaluate the level of fungal contamination in computer keyboards from an Integrated Health Center (IHC) at Piauí, Brazil, and to evaluate the efficacy of 50% sodium bicarbonate and 50% alcoholic vinegar solutions to eliminate these microorganisms. Ten keyboards from six sectors of the IHC were chosen randomly, and the collection was performed in three situations: (i) before of disinfection, (ii) after disinfection with solution of sodium bicarbonate, and (iii) after disinfection with solution of alcoholic vinegar. Samples were inoculated in Petri dishes with dextrose agar potato plus chloramphenicol and incubated at room temperature for 72 h. All keyboards were contaminated with opportunistic fungi, with Cladosporium cladosporioides (29.4%) being the most frequent species, followed by Curvularia lunata (17.6%) and Aspergillus niger, Alternaria alternata, and Curvularia clavata with 11.8% each. The two solutions were proven to be efficient in eliminating fungal contamination; however, the sodium bicarbonate solution caused esthetic damages in keyboards. In addition, this study is the first report of the antifungal activity of alcoholic vinegar in filamentous fungi. Based on our findings, we suggest a daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.

Endophytic fungi associated with Sudanese medicinal plants show cytotoxic and antibiotic potential.

In this study, we isolated 15 endophytic fungi from five Sudanese medicinal plants. Each fungal endophytic strain was identified by sequencing of internal transcribed spacer (ITS) regions of rDNA. Ethyl acetate extracts were prepared from each endophyte cultivated in vitro and tested for their respective antibacterial activities and antiproliferative activities against human cancer cells. Antibacterial screening was carried out against two bacterial strains: Gram-negative Escherichia coli and Gram-positive methicillin-resistant Staphylococcus aureus, by the broth dilution method. Cell viability was evaluated by the MTT procedure after exposure of MCF7 breast cancer cells and HT29 or HCT116 human colon adenocarcinoma cells to each endophytic extract. Of interest, Byssochlamys spectabilis isolated from Euphorbia prostata showed cytotoxicity (IC50 = 1.51 ± 0.2 µg mL(-1)) against MCF7 cells, but had a low effect against HT29 or HCT116 cells (IC50 > 20 µg mL(-1)). Cladosporium cladosporioides 2, isolated from Vernonia amygdalina leaves, showed antiproliferative activities against MCF7 cells (IC50 = 10.5 ± 1.5 µg mL(-1)) only. On the other hand, B. spectabilis and Alternaria sp. extract had antibacterial activities against the S. aureus strain. The findings of this work revealed that endophytic fungi associated with medicinal plants from Sudan could be considered as an attractive source of new therapeutic compounds.

Culture and molecular identification of fungal contaminants in edible bird nests.

Widespread food poisoning due to microbial contamination has been a major concern for the food industry, consumers and governing authorities. This study is designed to determine the levels of fungal contamination in edible bird nests (EBNs) using culture and molecular techniques. Raw EBNs were collected from five house farms, and commercial EBNs were purchased from five Chinese traditional medicine shops (companies A-E) in Peninsular Malaysia. The fungal contents in the raw and commercial EBNs, and boiled and unboiled EBNs were determined. Culturable fungi were isolated and identified. In this study, the use of these methods revealed that all EBNs had fungal colony-forming units (CFUs) that exceeded the limit set by Standards and Industrial Research Institute of Malaysia (SIRIM) for yeast and moulds in EBNs. There was a significant difference (p < 0.05) in the number of types of fungi isolated from raw and commercial EBNs, but no significant difference in the reduction of the number of types of fungi after boiling the EBNs (p > 0.05). The types of fungi isolated from the unboiled raw EBNs were mainly soil, plant and environmental fungi, while the types of fungi isolated from the boiled raw EBNs, unboiled and boiled commercial EBNs were mainly environmental fungi. Aspergillus sp., Candida sp., Cladosporium sp., Neurospora sp. and Penicillum sp. were the most common fungi isolated from the unboiled and boiled raw and commercial EBNs. Some of these fungi are mycotoxin producers and cause opportunistic infections in humans. Further studies to determine the mycotoxin levels and methods to prevent or remove these contaminations from EBNs for safe consumption are necessary. The establishment and implementation of stringent regulations for the standards of EBNs should be regularly updated and monitored to improve the quality of the EBNs and consumer safety.

Co-transformation of Panax major ginsenosides Rb1 and Rg1 to minor ginsenosides C-K and F1 by Cladosporium cladosporioides.

Rb1 and Rg1 are the major ginsenosides in protopanaxadiol and protopanaxatriol. Their content in ginsenosides was 23.8 and 17.6%, respectively. A total of 22 isolates of ß-glucosidase producing microorganisms were isolated from the soil of a ginseng field using Esculin-R2A agar. Among these isolates, the strain GH21 showed the strongest activities to convert ginsenoside Rb1 and Rg1 to minor ginsenosides compound-K and F1, respectively. Ginsenosides Rb1 and Rg1 bioconversion rates were 74.2 and 89.3%, respectively. Meanwhile, the results demonstrated that the ginsenoside Rg1 could change the biotransformation pathway of ginsenoside Rb1 by inhibiting the formation of the intermediate metabolite gypenoside-XVII. GH21 was identified as a Cladosporium cladosporioides species based on the internal transcribed spacers (ITS) ITS1-5.8S-ITS2 rRNA gene sequences constructed phylogenetic trees.

Different drying technologies and alternation of mycobiots in the raw material of Hyssopus officinalis L.

Contamination of medicinal plant mass with mycobiots is one of the negative factors deteriorating the quality of raw material. In order to evaluate the impact of the yield processing technologies upon the changes of mycobiots in raw material, the mycobiotic conditions of herb hyssop (Hyssopus officinalis L.) raw material were evaluated under various regimes of active ventilation and optimization of the drying parameters. The impact of ventilation intensity and temperature of drying agent upon the changes and abundance of mycobiota species in medicinal raw material was determined. Irrespective of the temperature of the airflow, the strongest suppressive effect upon the mycobiotic contamination in Hyssopi herba was produced by the 5,000 m3 x (t x h)(-1) airflow. Analysis of the isolated fungi revealed the prevalence of Penicillium, Aspergillus, Alternaria, Cladosporium, Mucor, Rhizopus species in the raw material. In separate samples Botrytis cinerea, Sclerotinia sclerotiorum, Aureobasidium pullulans, Chrysosporium merdarium, Cladorrhinum foecundissimum, Ulocladium consortiale, Trichoderma hamatum, T. harzianum, Gilmaniella humicola, Talaromyces flavus, Rhizomucor pusillus, Hansfordia ovalispora, Verticicladium trifi dum, Trichosporiella cerebriformis micromycetes were also rather abundant. Detection of the above-mentioned micromycetes in herb hyssop samples differed, and partially depended upon the medium used for their isolation.

Saprophytic fungus collection by Africanized bees in Brazil.

Cladosporium sp. collection by bees (Apis mellifera L.) was observed in Brazil at an apiary located in Minas Gerais, during November 10-23, 2005, characterized by high air relative humidity and low availability of food resources (pollen and nectar).The nutritional composition of the fungi pellets presented high protein value, ethereal extract and organic matter.

Saprophytic fungus collection by africanized bees in Brazil / Coleta de fungos saprofíticos por abelhas africanizadas no Brasil

Cladosporium sp. collection by bees (Apis mellifera L.) was observed in Brazil at an apiary located in Minas Gerais, during November10-23, 2005, characterized by high air relative humidity and low availability of food resources (pollen and nectar).The nutritional composition of the fungi pellets presented high protein value, ethereal extract and organic matter.

A coleta de Cladosporium sp. por abelhas (Apis mellifera L.) foi observada no Brasil em um apiário localizado em Minas Gerais, no período de 10 a 23/11/05, caracterizado pela alta umidade relativa do ar e escassez de recurso alimentar (pólen e néctar). A composição nutricional das bolotas de fungos apresentou alto valor protéico, extrato etéreo e matéria orgânica.

[Species composition of micromycetes from sugar beet leaves, roots and rhizospheres].

Species composition of fungi, isolated from the sugar beet leaves, roots and rhizosphere, collected in Poltava and Kyiv regions has been studied. Species Alternaria, Trichoderma, Cladosporium, Acremonium, Penicillium, Fusarium, Mycelia sterilia were found in all investigated samples. Basidiomycetes were isolated from the leaf samples in separate cases.

Utility of Etest in choosing appropriate agents to treat fungal keratitis.

PURPOSE: To evaluate the utility of Etest in choosing the appropriate treatment of fungal keratitis. METHODS: Etest was used to determine the drug sensitivities of isolates from the eyes of three patients with fungal keratitis, and the clinical outcomes of treatment with selected drugs were evaluated. RESULTS: In all cases, drug sensitivity demonstrated by Etest accorded with clinical efficacy of the drugs. CONCLUSION: The results in these cases suggest that evaluating drug sensitivities with Etest is an efficient means of selecting optimal pharmacotherapy for fungal keratitis.

Combined effects of aerobiological pollutants, chemical pollutants and meteorological conditions on asthma admissions and A & E attendances in Derbyshire UK, 1993-96.

BACKGROUND: The effect of outdoor aeroallergen exposure in asthma may be enhanced by air pollutants, including ozone, nitrogen dioxide and particulates, and by certain weather conditions. It is not yet established whether these interactions are important in determining asthma morbidity at the population level. OBJECTIVE: We have investigated the joint effects of aeroallergens, rainfall, thunderstorms and outdoor air pollutants on daily asthma admissions and Accident and Emergency (A & E) attendance using routinely collected data between 1993 and 1996 from Derby in central England. METHODS: Daily counts during the aeroallergen season of grass and birch pollen, basidiospores, Didymella, Alternaria and Cladosporium, maximum 1 hour ozone and nitrogen dioxide and daily average black smoke measurements, all made in the vicinity of the city centre, were categorized in tertiles. Rainfall was classified as dry, light ( 2 mm). The modifying effect of outdoor pollutant levels, and rainfall or the occurrence of a thunderstorm, upon the effects of individual aeroallergens on asthma admissions and A & E attendance were investigated by fitting appropriate interactions in log linear autoregression models with adjustment for potential confounders. RESULTS: We found a significant interaction between the effects of grass pollen and weather conditions upon A & E attendance, such that the increase with grass pollen count was most marked on days of light rainfall (adjusted rate ratio for >/= 50 vs < 10 grains/m3 at lag 2 days = 2.1, 95% CI 1.4, 3.3). Asthma admissions increased with Cladosporium count. We found no statistically significant interactions between effects of any individual aeroallergen and outdoor air pollutant upon either measure of asthma morbidity. CONCLUSIONS: Rainfall and thunderstorms are important effect modifiers in the relation between grass pollen and measures of acute asthma morbidity. Interactions between ambient levels of aeroallergens and chemical pollutants in the Derby area do not play a major role in determining asthma admissions and A & E attendance.