Seedborne mycoflora of faba bean (Vicia fabae L.) and evaluation of plant extract and Trichoderma species against mycelium growth of selected fungi

Fungal diseases are among the biotic factors limiting the production of faba bean in Ethiopia. The objective of this study was to isolate and identify seedborne mycoflora associated with faba bean seed samples, determine their effects on seed germination and disease transmission, and evaluate the antimicrobial activities of seven plant extracts and four Trichoderma spp. against the pathogen isolated from the seed. Fifty seed samples were collected from different farmers' saved seeds of five major faba bean-producing varieties of the Ambo district and were tested by agar plate methods as recommended by the International Seed Testing Association (ISTA). A total of 7 fungal species belonging to 6 genera, viz. Fusarium oxysporum (Schlechlendahl), Fusarium solani (Mart.) Sacc, Aspergillus spp. Penicillium spp. Botrytis spp. Rhizoctonia solani (Kühn) and Alternaria spp. were isolated and identified. Among these, Fusarium spp., Aspergillus spp, and Penicillium spp. were the most predominant fungi in all seed samples. Seed-to-seedling transmission test results confirmed that F. oxysporum, F. solani and R. solani were major causal pathogens that caused root rot and damping-off disease in faba beans and were transmitted from seeds to seedlings. A higher germination rate was observed in Golja-GF₂ (97%), and a lower germination rate was observed in Kure Gatira-KF₈ (81%). A study on in vitro evaluation of plant extract and Trichoderma spp. against F. oxysporum, F. solani and R. solani revealed that plant extracts at 5%, 10% and 20% concentrations significantly inhibited the mycelial growth of all tested fungi. Inhibitory effects on the three tested fungi (R. solani, F. solani and F. oxysporum) were recorded on T. longibrachiatum (87.91%), T. atroviride (86.87%), Trichoderma virens (86.16%) and T. harzianum (85.45%). The inhibitory effect of the aqueous plant extracts on mycelial growth increased with an increase in concentration, and the hot water extracts showed higher effects compared to the cold water extract in all tested fungi. This study showed that the highest inhibitory effect of Allium sativum L. extracted at a 20% concentration against mycelial growth inhibition of the three test fungi (F. oxysporum, R. solani and F. solani) was 84.60%, 83.61% and 83.47%, respectively. However, Nicandra physalodes (L.) Gaertn.) extracts at the same concentration showed the lowest inhibitory effects on the three tested fungi (74.94%, 73.94% and 73.24%).

Mycoflora isolation and molecular characterization of Aspergillus and Fusarium species in Tunisian cereals

Wheat, barley and maize are the mainly consumed cereals in Tunisia. This study aimed to determine the mycoflora of these cereals with special focus on the mycotoxigenic Aspergillus and Fusarium species. Freshly harvested samples and other stored samples of each type of cereal (31 and 34 samples, respectively) were collected in Tunisia and cultured for fungal isolation and identification. Identification of fungal genera was based on morphological features. Aspergillus and Fusarium species were identified by species specific PCR assays complemented with DNA sequencing. Alternaria (70.83%), Eurotium (62.50%), Aspergillus (54.17%) and Penicillium (41.67%) were the most frequent fungi isolated from wheat. Penicillium (75%), Aspergillus (70%), Eurotium (65%) and Alternaria (65%) were the most frequently recovered genera from barley. The predominant genera in maize were Aspergillus (76.19%), Eurotium (42.86%), and Penicillium (38.09%). Aspergilllus, Penicillium, Fusarium and Alternaria were detected in both stored and freshly harvested grain samples. The frequencies of contamination with Aspergillus, Fusarium and Alternaria were higher in freshly harvested samples, whereas Penicillium species were more frequent in stored samples. The predominant Aspergillus species detected were A. flavus and A. niger. The Fusarium species detected were F. equiseti, F. verticillioides, F. nygamai, and F. oxysporum. This study suggested the potential risk for Aflatoxins and, to a lesser extent, for Ochratoxin A in Tunisian cereals. This is the first survey about mycoflora associated with wheat, barley and maize in Tunisia.

Fr.) Kummer fruitbodies stored in two different packaging materials

The presence of fungi in our foods poses serious health risks as some genera of fungi may produce certain mycotoxins which have carcinogenic, mutagenic, teratogenic, and immunosuppressive effect on humans and animals alike. Fruitbodies of Pleurotus ostreatus were solar dried at a moisture content of 12.5 ± 0.2% and stored in polythene and polypropylene packs, gamma irradiated at doses of 0 (control), 1, 2, 3, 4, and 5 kGy at a dose rate of 1.7 kGy/hr from a Cobalt 60 source (SLL, 515, Hungary) and stored at room temperature 28-30°C for a period of 12 months. Mycological analyses were done at intervals of 0, 3, 6, and 12 months. A total of eleven (11) fungi belonging to eight fungal genera were isolated on both Cooke's and DRBC media; Aspergillus (A. niger, A. flavus, A. fumigatus, A. tamarii), Rhizopus (R. oligosporus), Mucor (M. racemosus), Fusarium (F. oxysporum), Penicillium (Penicillium sp.), Trichoderma (T. viride), and Rhodotorula sp. were recorded. There was a significant (p < .05) reduction in initial mycofloral population by an average of 2.2 log cycles as well as in species numbers with increasing doses of radiation. Radiation sensitivity (D₁₀ values) also ranged between 1.68-2.78 kGy. Gamma irradiation treatment is one way which can enhance food safety through the reduction in potential pathogens and has been recommended as part of a comprehensive program to enhance food safety.

Effect of Fungal Endophytes on Biomass Yield, Nutritive Value and Accumulation of Minerals in Ornithopus compressus

Yellow serradella (Ornithopus compressus), a valuable pasture species in Mediterranean areas, presents a high diversity of endophytic mycoflora. In the present work, the hypothesis of a significant effect of fungal endophytic species on the parameters of forage production, nutritive value and mineral status of herbage was tested. O. compressus plants were inoculated with each of seven endophytes (four in 2012/2013 and three in 2013/2014). After inoculation, two experiments (under greenhouse and field conditions) were established. Results evidenced a certain influence of several endophytes on herbage yield, nutritive value and mineral status of O. compressus forage. Byssochlamys spectabilis increased herbage biomass yield by around 42% in the field experiment. Stemphylium sp. improved the nutritive value of forage either by increasing crude protein, digestibility and the concentration of essential minerals (such as B, Mo, P or S) or by reducing the concentration of toxic elements such as Al or Pb. In conclusion, the results presented here provide evidence that plant inoculation with endophytes could be a suitable strategy to increase forage yield and its nutritive value or to deal with potential nutrient deficiencies or potential mineral toxicity in forage.

Metagenomic analysis of fungal diversity in Korean traditional wheat-based fermentation starter nuruk

Nuruk, a traditional natural starter, is extensively used in the brewing of Makgeolli, one of Korea's most popular alcoholic beverages that has been recently gaining global popularity. Thus, the quality of traditional nuruk needs to be enhanced. The nuruk mycobiome greatly influences both fermentation process as well as palatability enhancement. Limitations of culture-dependent identification restrict an accurate analysis of fungal diversity and distribution in nuruks. 454 pyrosequencing of two traditional wheat-based nuruks, prepared at two representative temperature conditions revealed a total of 153 and 53 OTUs for nuruks A and B, respectively, from a total of 33,157 ITS sequences. Phylogenetic assignments indicated that nuruk A mycobiota was dominated by the genera Aspergillus and Mucorales, whereas nuruk B by Rhizomucor. Species-level identification indicated that Mucorales sp., Aspergillus candidus, and Aspergillus cibarius predominated in nuruk A mycoflora whereas Rhizomucor pusillus, Mucorales sp., and Thermoascus crustaceus in nuruk B. The alpha diversity indices suggest nuruk A mycobiota to be more diverse than that of nuruk B at almost all time points of fermentation. Resemblances of patterns of predominant species composition and succession between culture-dependent and -independent phylogenetic analysis creates the potential to reconstruct the nuruk mycobiome in vitro, which allows the establishment of a standard inoculum for scientific comparison.

Study on mycoflora of poultry feed ingredients and finished feed in Iran

BACKGROUND AND OBJECTIVES

Unhygienic poultry feedstuffs can lead to nutrient losses and detrimental effect on poultry production and public health. In the present study, mycobiota and colony-forming units per gram in ingredients and finish poultry feed was evaluated with special reference to potentially mycotoxigenic fungi.

MATERIALS AND METHODS

Eighty five samples of corn, soybean meal and poultry finished feed were collected from nine poultry feed factories located in three provinces i.e. Tehran, Alborz and Qom in Iran from October 2014 to January 2015. Samples were cultured on Sabouraud dextrose agar (SDA), Aspergillus flavus and parasiticus agar (AFPA) and dichloran rosebengal chloramphenicol agar (DRBC) and incubated at 28 °C for 7-10 days. Purified fungal colonies were identified by a combination of macro- and microscopic morphological criteria. For determining the rate of fungal contamination, samples were cultured on SDA and colony forming units (CFUs) were calculated.

RESULTS

A total of 384 fungal isolates belonging to 7 genera of filamentous fungi and yeasts were obtained from corn (124 isolates), soybean meal (92 isolates), and feed before (72 isolates), and after pelleting (96 isolates). The most prominent fungal isolate in corn, soybean meal and feed before pelleting (feed as mash form) was Fusarium but in feed after pelleting was Aspergillus. Among 5 Aspergillus species isolated, potentially aflatoxigenic A. flavus isolates was predominant in corn (46.6%), soybean meal (72.7%) and poultry finished feed (75%). CFUs results indicated that 9/22 corn samples (40.9%), none of 22 soybean meal samples, 19/41 finished feed (46.3%) were contaminated higher than the standard limit.

CONCLUSIONS

Our results indicated that corn, soybean meal and finished feed of poultry feed mill are contaminated with various fungal genera by different levels sometimes higher that the standard limits. Contamination with potentially mycotoxigenic fungi especially Aspergillus species may be considered as a human public health hazard.

Isolation and comparative investigation of vaginal mycoflora in feline population of urban and dairy cattle herds

OBJECTIVE

The aim of this work was to identify the predominant fungal species present at vaginal site in different healthy cats including households, stray and cats in industrial dairy cattle herds.

MATERIALS AND METHODS

Fungal isolates of vaginal fluids of 100 cats were collected using the sterilized cotton swabs from discharges of vagina. The isolates were identified according to their morphological characteristics and biochemical profile. Were included 34%, 33% and 33% households, stray cats and cats of industrial dairy cattle herds of Mashhad-Iran, respectively. They were short hair cats.

RESULT

Vaginal fungi were isolated from 69% of feline population. Fungal isolates were obtained from vagina of 22%, 25% and 22% of households, stray cats and cats of industrial dairy cattle herds, respectively. There were no significant differences among the cats. The highest fungal agent was recovered in cats of 1-2 years old. Twenty two different isolates were recovered in this study. The most frequently recovered species samples were Penicillum spp. (11%) followed by Aspergillus section Nidulanti (4%). However, the vagina of healthy cats could be contaminated by 2-4 different fungal agents.

CONCLUSION

It is concluded that fungal infections can occur in vaginal cavity of different healthy kinds of cats.

Mycoflora of the interdigital spaces among girl students in ahvaz, iran

BACKGROUND

Fungi have been extensively isolated and investigated from skin in various parts of the world. Determining the mycoflora of normal people is important when the role of skin is considered as a reservoir for microorganisms.

OBJECTIVES

The current study aimed to investigate the incidence of fungal flora on interdigital spaces of the human foot.

PATIENTS AND METHODS

Samples were collected from interdigital spaces of 865 girl students who lived in the dormitories of Ahvaz Jundishapur University of Medical Sciences. A part of the sample was digested with 20% KOH and screened by a light microscope for fungal elements. Another part of the sample was cultured on Sabouraud glucose agar (SGA) and SGA containing 0.05 mg/mL chloramphenicol and 0.5 mg/mL cycloheximide. The fungal colonies were identified based on morphological and microscopic characteristics and biochemical tests.

RESULTS

In the current study, out of the 865 samples, 616 (71. 2%) were positive in direct examination or culture. Of these, 267 samples (30. 9%) were positive in direct examination. The most common fungal isolates in direct test were yeast (29. 4%), followed by conidia (0. 92%), melanised hypha (0. 35%) and non-septated hyphae (0. 23%). Trichophyton mentagrophytes was isolated in one of the specimens.

CONCLUSIONS

The present study demonstrated the incidence of fungal flora on interdigital spaces of human foot. The current study results showed that fungi can survive on surfaces of skin without showing the sign of infection.

Mycoflora and enzymatic characterization of fungal isolates in commercial meju, starter for a korean traditional fermented soybean product

Mycoflora was assessed in the commercial meju from four well-separated geographic origins. A total of 112 fungal isolates were identified by phenotypic characteristics and molecular taxonomy using sequencing the internal transcribed spacer of the rDNA and revealed 19 species from 13 genera. Enzymatic characteristics of protease and amylase, and mycotoxin production were analyzed.

Efficacy of Angelica archangelica essential oil, phenyl ethyl alcohol and α- terpineol against isolated molds from walnut and their antiaflatoxigenic and antioxidant activity

Mold association, aflatoxin B1 contamination as well as oxidative deterioration of agri-food items during storage and processing are some global task for food industries. In view of the adverse effects of some synthetic preservatives on treated food items and subsequently on consumers health, recently plant based chemicals are encouraged by food industries as better alternatives of synthetics. The present study recommends the combination (1:1:1) of Angelica archangelica essential oil: Phenyl ethyl alcohol (PEA): α- terpineol as botanical preservative against molds, aflatoxin contamination and oxidative deterioration of walnut samples. Eight mold species were procured from stored walnut samples, including some aflatoxigenic Aspergillus flavus strains. The combination inhibited growth of aflatoxigenic strain Aspergillus flavus NKDW-7 and aflatoxin B1 production at 2.25 and 2.0 μL mL(-1) respectively. The IC50 value of the combination was recorded as 3.89 μL mL(-1), showing strong antioxidant potential. The antifungal action of the combination showed > 90 % decrease in ergosterol content in plasma membrane of A. flavus at 2.0 μL mL(-1). The LD50 of the combination, through oral administration on mice, was 9562.9 μL kg(-1) body weight, indication favourable safety profile as a plant based preservative. The combination may be recommended as safe preservative against molds, aflatoxin contamination and oxidative deterioration of walnut samples.

The Effect of Seed-borne Mycoflora from Sorghum and Foxtail Millet Seeds on Germination and Disease Transmission

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vivo germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vivo germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops.

Natural occurrence of aflatoxin residues in fresh and sun-dried meat in Nigeria

INTRODUCTION

In recent times, food safety and security have generally remained basic human needs, therefore because of the largely unregulated nature of the Nigerian markets, coupled with the poor housing and feeding conditions to which animals are subjected in the abattoirs, a survey for assessing potential mycotoxin exposure through meat consumption was undertaken.

METHODS

Eighty Samples of meat bought randomly from 5 major markets distributed in 5 local government areas of Oyo state , Nigeria were analysed for contaminating mycoflora using the plate count and micromorphological methods, while aflatoxin detection and quantification was by Thin Layer Chromatography (TLC).

RESULTS

Mycological analysis of samples revealed a higher contamination level in the sun-dried samples. Eighteen fungi species belonging to 8 genera, namely, Aspergillus, Penicilliu, Alternaria, Cladosporium, Fusarium, Neurospora, Rhizopus and yeast were identified. The predominant genus Aspergillus yielded 7 species while the potential toxicogenic fungi represented 38% of the isolated mycoflora. The genera requiring higher water activity for growth ( Alternaria, Fusarium and yeast) were not obtained from the dried meat. Aflatoxins B1, B2, G1 and G2 were detected in all the samples analysed. The fresh samples with the exception of the total aflatoxin G (AFG) in kidney gave the highest mean concentrations for all aflatoxins, also an exceptionally high aflatoxin content was found in all the kidney samples.

CONCLUSION

Aflatoxin detection in meat should be addressed urgently to avert the possible adverse health effects like aflatoxicosis, exacerbated malnutrition, suppression of growth and immune functions on consumers. Also the animal health inspectors should pay more attention to the feeding conditions of the animals on farm and the abattoirs.