scholarly journals Isolation and Characterization of Contaminant Mycoflora from Stored Red Peppers

2021 ◽  
Author(s):  
R. Darsana ◽  
G. Chandrasehar
Keyword(s):  
Fungal Growth ◽  
Fungal Species ◽  
Red Pepper ◽  
Average Moisture Content ◽  
Indian States ◽  
Isolation And Characterization ◽  
Storage Fungi ◽  
Fungal Load ◽  
Red Peppers

Red pepper is a spice vulnerable to fungal growth and mycotoxin contamination while in the field and post-harvest during storage. Storage fungi are omnipresent and colonize fast when moisture levels go up, ultimately leading to mycotoxin production. Stored samples of the whole, crushed and ground red pepper in the Southern Indian States and Maharashtra, India were examined to isolate and characterize the prevalent contaminant fungal species. The average moisture content was below 10% for all the red pepper samples and the average total fungal load was less than 1×104 CFU/g. Crushed red pepper showed higher fungal counts than ground and whole red pepper. The identified contaminant mycoflora belonged to the group; Aspergillus, Eurotium sp., Cladosporium sp., Eupenicillium sp., Penicillium sp., Miscellaneous fungi, Neosartorya sp., Curvularia sp., and Hyphopichia sp. Aflatoxigenic Aspergillus flavus was present only in 8.3% of the crushed and 2.54% of whole red pepper samples stored for more than two months.

scholarly journals Effects of Temperature and Humidity on Fungal Occurrence in Dried Red Pepper during Storage

2021 ◽  
Vol 27 (4) ◽  
pp. 155-163
Author(s):  
Sosoo Kim ◽  
Seul Gi Baek ◽  
Nguyen Bao Hung ◽  
Se-Ri Kim ◽  
Ja Yeong Jang ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Fungal Growth ◽  
Red Pepper ◽  
Aspergillus Sydowii ◽  
Fruit Samples ◽  
Effects Of Temperature ◽  
Penicillium Solitum ◽  
Red Peppers ◽  
Pepper Powder ◽  
Red Pepper Powder

Dried red peppers are frequently contaminated with mycotoxins during storage. To determine the effect of storage environments on fungal occurrence and subsequent mycotoxin accumulation in dried red peppers, we monitored red pepper powder and whole fruit samples for fungal occurrence under various temperatures and relative humidity (RH) conditions during 340 days. Fungal occurrences fluctuated in both pepper forms throughout the storage but they were higher in pepper powder than whole one, higher under low temperatures (-20°C, 0°C, or 4°C) than others (10°C, 25°C, or 30°C), and higher under RH 93% than RH 51% and 69% in both peppers. The samples exhibiting high fungal occurrences were associated mainly with dominant species such as Aspergillus sydowii, Penicillium solitum, P. roqueforti, P. polonicum, or P. chrysogenum. Mycotoxigenic species, including A. flavus, A. ochraceus, A. westerdijkiae, A. tubingensis, and P. citrinum, were also detected throughout the samples. Although mycotoxins were not detected in the samples, mycotoxigenic potential of A. flavus, A. ochraceus, and A. westerdijkiae isolates were confirmed. These results show that low temperatures (-20°C, 0°C, or 4°C) and/or high surrounding RH (>93%) are not safe environments for storage of dried red peppers as fungal growth can occur under these conditions.

Isolation and characterization of conditional lethal mutants of Beauveria bassiana

1994 ◽  
Vol 40 (9) ◽  
pp. 766-776 ◽  
Author(s):  
Dwayne D. Hegedus ◽  
George G. Khachatourians
Keyword(s):  
Cell Wall ◽  
Beauveria Bassiana ◽  
Fungal Growth ◽  
Enzyme Synthesis ◽  
Temperature Sensitive ◽  
Temperature Sensitive Mutants ◽  
Isolation And Characterization ◽  
Mutant Strains

Temperature-sensitive mutants of Beauveria bassiana GK2016 were isolated and characterized. Heat-sensitive mutants that grew at 20 °C but not at 30 °C were generated using mutagenesis with ultraviolet light and several rounds of selection. After 2160 colonies from a heat-sensitive mutant enriched population were screened, 11 heat-sensitive strains were isolated for further study. Five mutant strains, HS1, HS2, HS6, HS9, and HS11, were stable and closely resembled the wild-type strain with respect to morphology, growth rate, and enzyme synthesis at 20 °C. Characterization of macromolecular synthesis at 30 °C using a radiolabelled precursor uptake assay indicated that three mutants, HS6, HS9, and HS11, had reduced levels of DNA, RNA, and protein synthesis at the nonpermissive temperature. Mutants affected in cell division and cell wall synthesis were characterized by microscopy. At 30 °C, mutant HS6 was defective in cellular compartmentalization and formed long, branched, aseptate mycelia that fragmented easily. Mutant HS1 was defective in cell wall biosynthesis and at 30 °C ceased to maintain cell wall integrity and lysed. Mutants HS2 and HS9 possessed temperature-sensitive lesions that could not be specified. None of the mutants were directly affected in either nuclear division or mitosis as evidenced by the accumulation of Giemsa-stainable mitotic nuclei at 30 °C. Bioassays conducted with grasshoppers showed the efficacy of the mutant strains, with the exception of HS11, to be comparable to that of the parent strain, at 20 °C. Conversely, at 32 °C the mutant strains were uninfective whereas the parental strain GK2016 was infective. It is our intention to use these strains to examine fundamental aspects of entomopathology by dissecting fungal growth and development in vitro and extending these observations to pathogenesis in insects.Key words: Beauveria bassiana, temperature-sensitive, mutants, characterization, infection.

scholarly journals Isolation and Characterization of the Mycorrhiza Helper Bacteria from the Fairy Rings of Floccularia Luteovirens

2020 ◽  
Author(s):  
minghang xu ◽  
Rui Xing ◽  
Qing-bo Gao ◽  
Fa-qi Zhang ◽  
Shi-long Chen
Keyword(s):  
Fungal Growth ◽  
Ectomycorrhizal Fungus ◽  
Tibet Plateau ◽  
Mycorrhizal Symbiosis ◽  
Bacterial Isolates ◽  
Mycorrhiza Helper Bacteria ◽  
Isolation And Characterization ◽  
Fairy Rings ◽  
Qinghai Tibet Plateau

Abstract Floccularia luteovirens is an edible ectomycorrhizal fungus which forms fairy rings (FRs) distributed on the Qinghai-Tibet Plateau. Our previous study found four isolates of potential mycorrhiza helper bacteria (MHB), but they were only isolated from a single FR and their mycorrhizal promoting ability was not tested. Thus, it was necessary to collect samples from a larger area and measure the mycorrhizal promoting ability of the potential candidates. Of 184 bacterial isolates from five fairy rings located in Qinghai-Tibet Plateau belonging to 12 species, and 7 of them (58.3%) significantly promoting the growth of F. luteovirens. We also tested the symbiosis-promoting ability of the isolates, and the results showed that only four of them stimulated the formation of mycorrhizal symbiosis. This is the first report of the construction of mycorrhizal symbiosis between F. luteovirens and its host plant in greenhouse conditions. Our results showed that the strain A89 (Achromobacter marplatensis) could produce antifungal properties but nonetheless stimulated the fungal growth. This may due to the nutrient condition of medium and the genotype specificity of MHBs. The results suggest that the promotion of significant growth is not a good predictor for mycorrhiza formation promotion ability of MHB.

scholarly journals A Review of Mycotoxin Types, Occurrence, Toxicity, Detection Methods and Control

2019 ◽  
Vol 62 (3) ◽  
pp. 206-218
Author(s):  
Naseem Zahra ◽  
Muhammad Khalid Saeed ◽  
Asma Sheikh ◽  
Imran Kalim ◽  
Sajid Rashid Ahmad ◽  
...  
Keyword(s):  
Human Health ◽  
High Temperatures ◽  
Environmental Conditions ◽  
Fungal Growth ◽  
Fungal Species ◽  
Detection Methods ◽  
Storage Fungi ◽  
Food And Feed ◽  
And Control ◽  
Hygienic Conditions

Mycotoxins are health hazardous natural toxin produced by various fungal species due to favourable environmental conditions for fungal growth. These are carcinogenic, hepatotoxic and immuno- suppressive substances usually found in food and feed items. Mycotoxins are broadly divided into two major groups on the basis of mycotoxin producing fungi i.e., those fungi which invade in pre-harvest conditions and those which are produced in post-harvest conditions called storage fungi. The conditions which promote mycotoxin growth are high temperatures, moisture levels, poor hygienic conditions and contamination during storage and transportation. Aflatoxins, ochratoxins, citrinin, trichothecene, fumonisins, patulin and zearalenone are prominent mycotoxins in food and feed commodities. This review renders the comprehensive data regarding occurrence of main mycotoxins, their analysis and health hazardous effects on human health alongwith some detoxification protocols.  

scholarly journals Isolation and Characterization of Fungal Species from Spoilt Fruits in Utako Market, Abuja, Nigeria

2018 ◽  
Vol 19 (1) ◽  
pp. 15-19
Author(s):  
Mairami Fatima Muk ◽  
Ndana Rebecca Wu ◽  
Umar Iliya Danl ◽  
Nura Salisu
Keyword(s):  
Fungal Species ◽  
Isolation And Characterization

scholarly journals Preliminary Studies on Fungal Contamination of Two Rupestrian Churches from Matera (Southern Italy)

2020 ◽  
Vol 12 (17) ◽  
pp. 6988
Author(s):  
Stefania Mirela Mang ◽  
Laura Scrano ◽  
Ippolito Camele
Keyword(s):  
Fungal Species ◽  
World Heritage Site ◽  
Detailed Knowledge ◽  
Unesco World Heritage ◽  
Isolation And Characterization ◽  
Heritage Site ◽  
Unesco World Heritage Site ◽  
Lecanicillium Psalliotae ◽  
Very High

The Sassi, a UNESCO World Heritage Site and its rupestrian churches, are richly decorated and visited by thousands of visitors every year. It is important to preserve this heritage which shows signs of deterioration due to abiotic and/or biotic factors. Aiming to carry out in the future an environmental-friendly restoration, a screening of the fungi present on walls and frescoes of two rupestrian churches “Santa Lucia alle Malve” and “La Madonna dei derelitti” located, respectively, in the “Sasso Caveoso” and in the “Sasso Barisano” was performed. Isolation and characterization of fungal species from investigated sites was carried out. Total genomic DNA (gDNA) was extracted from pure fungal cultures and subsequently utilized in PCRs using primers that amplify a portion of the ribosomal DNA (ITS5/ITS4) or the β-tubulin gene (Bt2a/Bt2b). The amplicons were directly sequenced. Obtained nucleotide sequences were compared to those present in the GenBank (NCBI) showing a very high similarity (99–100%) with the following species: Parengyodontium album, Alternaria alternata, Cladosporium cladosporioides, Lecanicillium psalliotae, Meyerozyma guilliermondii and Botryotrichum atrogriseum. All sequences from this study were deposited in the EMBL database. Detailed knowledge about fungi isolated from stone is indispensable not only to counter/reduce the structural and aesthetic damage but also to protect the health of both guardians and visitors who may develop different pathologies due to the spores diffused in the environment.

scholarly journals Isolation and characterization of fungi from deteriorated old manuscripts from Banyumas, collection of Library of Universitas Indonesia

2021 ◽  
Vol 948 (1) ◽  
pp. 012031
Author(s):  
W Lintang ◽  
T Susetyo-Salim ◽  
A Oetari ◽  
W Sjamsuridzal
Keyword(s):  
Electron Microscopy ◽  
Fungal Spores ◽  
Carbon Sources ◽  
Morphological Characteristics ◽  
Fungal Growth ◽  
Dry Weight ◽  
Isolation And Characterization ◽  
Fungal Isolates ◽  
Scanning Electron

Abstract Fungi are the main cause of old manuscript deterioration since manuscripts provide carbon source and nutrient for fungal growth. Isolation of fungi from deteriorated old manuscripts from Banyumas was carried out and their morphology, xerophilic, and cellulolytic nature were investigated. Two deteriorated old dluwang manuscripts showed fungal spores, brown spots, and discoloured paper. Based on morphological characteristics, 31 fungal isolates belonged to five genera (Aspergillus Micheli, Cladosporium Link, Curvularia Boedijn, Penicillium Link, Ulocladium Preuss). These genera have been reported from deteriorated old manuscripts from several historical places in Indonesia. Xerophilic character was shown by 90% (28 isolates) as determined by growth in DG18 medium, which indicated the ability to grow in dry substrates such as old manuscripts. Cellulolytic character was shown by 93.5% (29 isolates) as determined by growth in dluwang paper and merang paper, which indicated that the papers were used as carbon sources and substrates. After 30 days-incubation, the dry weight loss of merang paper was 0.28-51.2%. Result from Scanning Electron Microscopy showed that the deterioration of merang paper were caused by the isolates as shown by the presence of fungal structures. These results showed that the fungal isolates were able to deteriorate old manuscripts from Banyumas, Indonesia.

scholarly journals Quality Evaluation of Dried Fermented Locust Bean and Soybean Condiments

2021 ◽  
Vol 3 (2) ◽  
pp. 63-67
Author(s):  
Evelyn Mnguchivir Tersoo-Abiem ◽  
Stephen Sule ◽  
Izuchukwu Iwuamadi ◽  
Esther Obiye Awulu
Keyword(s):  
Fungal Growth ◽  
Plate Count ◽  
Fermented Soybean ◽  
Isolation And Characterization ◽  
Significant Difference ◽  
The Common ◽  
Locust Bean ◽  
African Locust Bean ◽  
Β Carotene

The study was carried out in order to establish the suitability of fermented soybean condiment as an alternative to fermented locust bean condiment in meal preparations. The dried fermented condiments were subjected to chemical, microbial and sensory evaluation using standard methods. Results revealed significantly (p<0.05) higher protein (54.06%), ash (6.21%), crude fat (14.15%) and pH (8.90) content in fermented soybean condiment. Higher values of 44.72 mg/100 g, 20.06 mg/100 g, 612.40 mg/100 g and 164.34 mg / 100 g were also observed in fermented soybean condiment with respect to iron, magnesium, potassium, and calcium respectively. Furthermore, fermented soybean condiment revealed significantly (p<0.05) higher vitamin content of 647.62 UI/100 g, 0.047 mg/100 g and 0.030 mg/100 g for pro-vitamin A (β-Carotene), vitamins B1 and B2 respectively. Microbiologically, total plate count of 1.7×105 CFU/g and 1.4×105 CFU/g were observed for fermented soybean and locust bean condiments respectively. There was however no fungal growth observed in both condiments. Isolation and characterization of bacteria isolates revealed Bacillus subtilis as the common microorganism in both condiments. Bacillus licheniformis was predominant in locust bean condiment, while Bacillus pumilus was more in soybean condiment. With the exception of appearance, there was no significant difference (p>0.05) between the condiments in terms of their sensory attributes. Sensory scores for fermented soybean condiment were however higher than that of fermented African locust bean. From this study, soybean condiment may be a suitable substitute to locust bean (Parkia biglobosa) condiment, following the gradual extinction of the plant.

Isolation and Characterization of New Metschnikowia pulcherrima Strains as Producers of the Antimicrobial Pigment Pulcherrimin

2009 ◽  
Vol 64 (5-6) ◽  
pp. 405-410 ◽  
Author(s):  
Sezai Türkel ◽  
Beyza Ener
Keyword(s):  
Antimicrobial Activities ◽  
Fungal Species ◽  
Antagonistic Effect ◽  
Its2 Region ◽  
Human Pathogens ◽  
Trichoderma Spp ◽  
Isolation And Characterization ◽  
Metschnikowia Pulcherrima ◽  
Different Strains

Metschnikowia pulcherrima is a highly effective biocontrol yeast due to its pigment pulcherrimin that accumulates in the cells and in the growth medium. Three different strains of M. pulcherrima were isolated from local grapes. The yeast isolates were characterized on the basis of their biochemical, physiological and ITS1-5.8 s rDNA-ITS2 region. Based on the obtained results, the M. pulcherrima isolates were identifi ed as new strains of M. pulcherrima. Strong antagonistic activities of the M. pulcherrima strains on the human pathogens Proteus vulgaris, Escherichia coli, Candida albicans, Candida parapsilosis, Candida krusei, and Trichosporon mucoides were determined. In addition, antagonistic effects of these M. pulcherrima strains were also tested against Aspergillus fl avus, Aspergillus fumigatus, Aspergillus niger, Trichoderma spp., Paecilomyces spp., and Bipolaris spp. and it was shown that the three different strains of M. pulcherrima also have an antagonistic effect on the growth of these fungal species at different extents. This study showed that all three strains of M. pulcherrima produce the same amount of the pigment pulcherrimin, but their antimicrobial activities on different microorganisms show important variations

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