scholarly journals Occurrence of Aflatoxigenic Aspergillus Species in Various Varieties of Peanuts Produced in Western Kenya

2017 ◽  
Author(s):  
Menza C. Nelson ◽  
Muturi W. Margaret ◽  
Lucy Kamau
Keyword(s):  
Aspergillus Flavus ◽  
Dominant Species ◽  
Aspergillus Parasiticus ◽  
Cyclopiazonic Acid ◽  
Aspergillus Species ◽  
Western Kenya ◽  
Central District ◽  
Aspergillus Section

Aflatoxin contaminates foods including peanuts. Aflatoxin is a carcinogenic toxin mainly produced bty Aspergillus flavus. Other Aspergillus species that rarely produce aflatoxins are A. nomius and A. niger. Aflatoxin is associated with liver failure, hepatocellular carcinoma (HCC) and death. Recent studies have shown that peanuts in Kenya are highly contaminated with aflatoxins but information gaps exist on the characterization of the Aspergillus species that produce aflatoxins in peanuts in Kenya. Therefore, this gap necessitated the determination of the Aspergillus species producing aflatoxins in peanuts from the main growing districts of Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district Aspergillus species were isolated from the peanut samples by using the dilution plate technique on modified Rose Bengal agar. Phenotypical characterization of the identified Aspergillus section flavus isolates from the peanuts samples was determined using the procedure of Mellon and Cotty. This study identified five (5) Aspergillus species as contaminants in peanuts analyzed in this study. They were Aspergillus flavus L-strain, Aspergillus flavus S-strain, Aspergillus parasiticus, Aspergillus niger and Aspergillus tamari. Overall, the occurrence of Aspergillus flavus L- strain and A. flavus S- strain were significantly higher than other species identified (H = 15.55, df = 4, P = 0.004) in peanuts from the two districts. However, A. flavus S-strain was the most dominant species identified in the study with a mean occurrence of 45.1%. Aspergillus flavus L- strain was the most common isolate (58.8%) in peanuts from Busia district while A. flavus S- strain was the most common strain (60.2%) in peanuts from Kisii Central district. Overall, the occurrence of Aspergillus flavus L strain and A. flavus S strain were significantly higher than other species identified (H = 15.55, df = 4, P = 0.004) in peanuts from the two districts. However, A. flavus S-strain was the most dominant species (F=3.15, df =25, P=0.031) with an overall mean occurrence of 45.1%. The confirmation of occurrence of other species that produce toxins such as A. niger and A. tamarii which also produces cyclopiazonic acid suggests the need to screen peanuts for other carcinogenic mycotoxins.

scholarly journals Isolation and Molecular Characterization of Aspergillus fumigatus and Aspergillus flavus Isolated from Poultry Birds in Ado- Ekiti, Nigeria

2020 ◽  
pp. 31-44
Author(s):  
E. D. Fagbohun ◽  
K. J. Ayantola ◽  
A. J. Toyin-Famoroti
Keyword(s):  
Aspergillus Fumigatus ◽  
Molecular Characterization ◽  
Aspergillus Flavus ◽  
Clinical Signs ◽  
Signs And Symptoms ◽  
Aspergillus Species ◽  
Exercise Intolerance ◽  
State University ◽  
Poultry Farms

Aim: The study was carried out to isolate and identify Aspergillus species from commercial birds with suspected aspergillosis in the poultry farms within Ado Ekiti metropolis Nigeria.  Place and Period of Study: The study was carried out in the Department of Microbiology, Faculty of Science, Ekiti State University Ado Ekiti, Nigeria in August 2016. Methodology: A total of 35 sick/suspected birds were collected randomly from three poultry farms. At Ago-Aduloju poultry farms, 15 samples were randomly collected from 1000 birds while at Ekiti State University poultry farms, 10 samples were randomly collected from 500 birds. At Federal Polytechnic Ado Ekiti poultry farms, 10 samples were randomly collected from 700 birds. The bird’s selection was on the basis of clinical signs and symptoms such as difficulty in breathing, weight loss, drooping of wings and exercise intolerance. Swab samples were collected from each suspected/sick bird for mycological culture and molecular characterization of the isolates from each bird was carried out. The isolates were identified based on the color of the culture on Potato Dextrose Agar and microscopic examination. Molecular identification was done using 23S Ribosomal RNA Gene and Partial Sequence. Results: Six fungal strains that showed similar morphological and cultural characteristics of Aspergillus species were isolated. The isolates were coded ASP 1, ASP 2, ASP 3, ASP 4, ASP 5, and ASP 6. The identified organisms were; Aspergillus fumigatus qH 107 (ASP 1), Aspergillus fumigatus qH 107 (ASP 2), Aspergillus flavus M09 (ASP 3), Aspergillus flavus UOMS6 (ASP 4), Aspergillus fumigatus qH 107 (ASP 5), Aspergillus flavus qH 107 (ASP 6). Conclusion: It is evident that Aspergillus species were predominant in poultry farms selected in this study. Necessary precaution should be put in place to prevent the spread of aspergillosis. Poultry farmers are advised to avoid damp environments, moldy feeds, dry and dusty litters. Adequate ventilation should always be provided in poultry farms to prevent Aspergillosis.

Relationship between soil densities ofAspergillusspecies and colonization of wounded peanut seeds

2006 ◽  
Vol 52 (10) ◽  
pp. 951-960 ◽  
Author(s):  
Bruce W Horn
Keyword(s):  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Fungal Species ◽  
Aspergillus Species ◽  
Soil Density ◽  
Peanut Seed ◽  
Wound Site ◽  
Seed Colonization ◽  
The Relationship ◽  
Fungal Competition

Soil is a reservoir for Aspergillus flavus and A. parasiticus, fungi that commonly colonize peanut seeds and produce carcinogenic aflatoxins. Densities of these fungi in soil vary greatly among fields and may influence the severity of peanut infection. This study examined the relationship between soil density of Aspergillus species and the incidence of peanut seed colonization under laboratory conditions. Viable peanut seeds were wounded and inoculated with 20 soils differing in composition and density of Aspergillus species and were then incubated for 14 days at 37 °C (seed water activity = 0.92). The effect of soil density of individual section Flavi species (A. flavus strains L and S, A. parasiticus, A. caelatus, and A. tamarii), section Nigri, and A. terreus on the incidence of seed colonization was best expressed as a function of exponential rise to maximum. Exponential curves often rose to maximum percentages of seed colonization by section Flavi species that were well below 100% despite high species densities in some soils. Competition primarily among section Flavi species may explain the reduced incidences of seed colonization. An average of two or fewer propagules of each Aspergillus species in the soil at the wound site was required for colonization of 20% of peanut seeds. Other fungal species were capable of invading peanut seeds only when soil densities of sections Flavi and Nigri species were low.Key words: aflatoxin, Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, fungal competition.

scholarly journals Bioinformatics analysis of aflatoxins produced by Aspregillus sp. in basic consumer grain (corn and rice) in Saudi Arabia

10.5219/1020 ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 65-75
Author(s):  
Latifa Al Husnan ◽  
Muneera Al Kahtani ◽  
Randa Mohamed Farag
Keyword(s):  
Aspergillus Flavus ◽  
Epitope Prediction ◽  
Agricultural Practices ◽  
Antigenic Determinants ◽  
Toxin Gene ◽  
Food Contaminants ◽  
White Rice ◽  
Yellow Corn

The food contaminants by aflatoxins are inevitable even when all precautions and good agricultural practices are applied. Samples of white rice and corn (yellow, red) grains were collected from different local markets and houses. Three Aspergillus flavus strain isolated were identified using molecular characterization of AFLR (aflR) toxin gene. DNA genome of the three A. flavus isolates (namely A. flavus _ YC; A. flavus _ RC; A. flavus _ Rice) which corresponds to isolates from, yellow corn, red corn and white rice respectively were used as a template for PCR to amplify Aspergillus flavus AFLR (aflR) toxin gene. Partially sequenced was amplified using a specific primer set to confirm its identity, phylogenetic relationships between the three isolates as well as determination of the corresponding antigenic determinants. The epitope prediction analysis demonstrated that there were 1, 2, 3 and 4 epitopes whose score were equal 1 in A. flavus _ YC; A. flavus _ RC; A. flavus _ Rice, respectively. Interestingly, there were great dissimilarity in the epitope sequences among the three isolates except in RLQEGGDDAAGIPA, SPPPPVETQGLGGD, RPSESLPSARSEQG and PAHNTYSTPHAHTQ were found to be similar between all isolates. This work articulates that the molecular identification and characterization of three A. flavus using Aspergillus flavus AFLR (aflR) toxin gene and the unique antigenic determinants that could be used for design of a broad-spectrum antibody for rapid detection of A. flavus in foods and support quality system of food safety.

scholarly journals Biofilm Mode of Cultivation Leads to an Improvement of the Entomotoxic Patterns of Two Aspergillus Species

2020 ◽  
Vol 8 (5) ◽  
pp. 705
Author(s):  
Frédéric Francis ◽  
Florent Druart ◽  
José Diana Di Mavungu ◽  
Marthe De Boevre ◽  
Sarah De Saeger ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Secondary Metabolite ◽  
Aspergillus Flavus ◽  
Aspergillus Oryzae ◽  
Proteomic Analysis ◽  
Cyclopiazonic Acid ◽  
Aspergillus Species ◽  
Metabolite Profiles

Two fungi, i.e., Aspergillus flavus Link and Aspergillus oryzae (Ahlb.) E. Cohn, were cultivated according to two methodologies, namely submerged and biofilm cultures with the primary aim to use their secondary metabolites the supernatant CL50, and CL90 varied between 1.3% (v/v) to 12.7% (v/v) for incubation times from 24 to 72 h. While the A. flavus supernatant entomotoxicity was higher than this of A. oryzae, the biofilm culture application increased the efficiency of the former. Proteomic analysis of the supernatants revealed discrepancies among the two species and modes of cultivation. Furthermore, the secondary metabolite profiles of both Aspergillus cultures were verified. Aspergillic acid, beta-cyclopiazonic acid, cyclopiazonic acid, ferrineospergillin, flavacol, and spermadin A were most predominant. Generally, these secondary metabolites were present in higher concentrations in the supernatants of A. flavus and biofilm cultures. These molecular identifications correlated positively with entomotoxic activity. Noteworthy, the absence of carcinogenic aflatoxins was remarkable, and it will allow further valorization to produce A. flavus to develop potential biopesticides.

scholarly journals Synthesis and Evaluation of Lipid-based Nanoparticle Containing Ginger Extract against Aspergillus Species

2020 ◽  
Author(s):  
Vahid Yakhchi ◽  
Shabnam Jahanizadeh ◽  
Fatemeh Yazdian ◽  
Hamid Rashedi ◽  
Bibi Fatemeh Haghiralsadat
Keyword(s):  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Chemical Interaction ◽  
Drug Stability ◽  
Inhibitory Effect ◽  
Ginger Extract ◽  
Antifungal Effect ◽  
Experimental Laboratory

Introduction: Loading the active ingredients of medicinal plants in lipid nanoparticles reduces the reaction of the active substance with the surrounding environment, such as water and oxygen, and reduces the intensity of transmission or evaporation to the external environment. In this study, intended to enhance efficacy of ginger extract, encapsulation in nanoliponiosome synthesized by thin-film hydration method were done and their antifungal effect on the growth of Aspergillus flavus and Aspergillus parasiticus were studied. Methods: In this experimental laboratory study, derivation was done using Soxhlet extractor method. Antifungal activity of ginger extract was specific by disc diffusion and microplate dilution methods. The inhibitory effect of extract was investigated. Physiochemical characteristics and structural characterization of nanoparticle were evaluated from the perspective of in vitro efficiency, drug release, nanoparticle size, zeta potential, surface morphology and FTIR (Fourier-transform infrared spectroscopy), DLS (Dynamic light scattering) and finally SEM (Scanning electron microscope) spectra. Results: FTIR investigations showed ginger extract and nanoliponiosome had no chemical interaction leading to change the functional groups. SEM microscope showed the spherical mprphology of particles and average particles size of 73nm. Ginger extract was loaded into the nanoliponiosome with a yield of 71%. It was also found out that ginger extract had a stronger antifungal effect against Aspergillus flavus fungus compared to the Aspergillus parasiticus fungus. At both 37°C and 42°C, the release of ginger extract was higher at pH of 4.5 compared to neutral pH (7.4). Conclusion: Nanoliponiosomes containing ginger extract with good physicochemical properties, increased drug stability and good release control can be promising antifungal agents with high antifungal effects and low side effects.

scholarly journals Production of Bright Greenish Yellow Fluorescence in Figs Infected by Aspergillus Species in California Orchards

Plant Disease ◽  
1998 ◽  
Vol 82 (6) ◽  
pp. 669-673 ◽  
Author(s):  
Mark A. Doster ◽  
Themis J. Michailides
Keyword(s):  
Aspergillus Flavus ◽  
Uv Light ◽  
Fungal Species ◽  
Fungal Strain ◽  
Aspergillus Species ◽  
Yellow Fluorescence ◽  
Greenish Yellow ◽  
Relationship Of ◽  
The Relationship ◽  
Aspergillus Section

The relationship of bright greenish yellow fluorescence (BGYF) of dried figs under longwave UV light to colonization by Aspergillus fungi was determined. BGYF in naturally infected figs was associated with decay by only four fungal species: the aflatoxin-producing species Aspergillus flavus (both L and S strains) and A. parasiticus, and the aflatoxin nonproducers A. tamarii and A. alliaceus. BGYF was more likely to be visible internally (after cutting open the fig) than externally. For all four species associated with BGYF, some infected figs did not show BGYF. The absence of fluorescence is probably not associated with the fungal strain or isolate involved, since isolating Aspergillus spp. from nonfluorescent figs followed by inoculating other figs with these isolates resulted in BGYF. Many of the nonfluorescent figs had small fungal colonies (<7 mm in diameter), even though some figs with large colonies were also nonfluorescent. The additional colonization of figs by other fungi did not affect the occurrence of BGYF in figs colonized by fungi in Aspergillus section Flavi. Figs infected with A. flavus or A. parasiticus and showing no BGYF were occasionally contaminated with aflatoxin, while other figs showing BGYF and infected with A. flavus or A. tamarii had no aflatoxins. Although not as promising as originally hoped, BGYF might be of use to remove aflatoxin-contaminated figs for certain specific situations in California.

scholarly journals Liquid Chromatographic Determination of Major Secondary Metabolites Produced by Aspergillus Species from Section Flavi

1998 ◽  
Vol 81 (1) ◽  
pp. 57-60 ◽  
Author(s):  
Victor S Sobolev ◽  
Bruce W Horn ◽  
Joe W Dorner ◽  
Richard J Cole
Keyword(s):  
Secondary Metabolites ◽  
Cyclopiazonic Acid ◽  
Chromatographic Determination ◽  
Normal Phase ◽  
Aspergillus Species ◽  
Uv Detector ◽  
Tetrabutylammonium Hydroxide ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method was developed for simultaneous determination of major secondary metabolites—including cyclopiazonic acid (CPA), O-methylsterigmatocystin (OMST), and the versicolorins—produced by Aspergillus species from section Flavi (A. flavus, A. parasiticus, A. tamarii, and A. caelatus) on a liquid medium. Metabolites were extracted with chloroform and quantitated without prior cleanup by means of normal- phase ion-pair partition LC on silica gel with a mobile phase of n-heptane-2-propanol-n-butanolwater- tetrabutylammonium hydroxide (2560 + 900 + 230 + 32 + 8, v/v). Recoveries of CPA and OMST from fungal cultures spiked at 10 μg/mL were 98.90 + 3.27 and 95.92 + 5.27% (n = 5), respectively. At spike levels of 100 μg/mL, recoveries were 98.89 + 3.87 and 97.65 + 4.32% (n = 5), respectively. Limits of detection for pure standards were 0.25 μg/mL for CPA (at 280 nm) and 0.30 μg/mL for OMST (at 310 nm). UV detector responses to CPA and OMST were linear to about 0.5 and 3.5 μg/injection, respectively

Monitoring and Determination of Fungi and Mycotoxins in Stored Brazil Nuts

2013 ◽  
Vol 76 (8) ◽  
pp. 1414-1420 ◽  
Author(s):  
ARIANNE COSTA BAQUIÃO ◽  
MAITÊ M. M. DE OLIVEIRA ◽  
TATIANA A. REIS ◽  
PATRÍCIA ZORZETE ◽  
DANIELLE D. ATAYDE ◽  
...  
Keyword(s):  
High Performance ◽  
Management Practices ◽  
Cyclopiazonic Acid ◽  
Aflatoxin Production ◽  
Brazil Nut ◽  
Brazil Nuts ◽  
Aspergillus Section Flavi ◽  
Penicillium Spp ◽  
Aspergillus Section

Brazil nut (Bertholletia excelsa) is an important commodity from the Brazilian Amazon, and approximately 37,000 tons (3.36 × 107 kg) of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs, with subsequent production of mycotoxins. In this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated Brazil nut (55 samples of nuts and 55 samples of shells) collected monthly for 11 months in Itacoatiara, State of Amazonas, Brazil. The samples were inoculated in duplicate onto Aspergillus flavus and Aspergillus parasiticus agar and potato dextrose agar for the detection of fungi, and the presence of mycotoxins was determined by high-performance liquid chromatography. The most prevalent fungi in nuts and shells were Aspergillus spp., Fusarium spp., and Penicillium spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The low water activity of the substrate was a determinant factor for the presence of fungi and the absence of aflatoxin in Brazil nut samples. The high frequency of isolation of aflatoxigenic Aspergillus section Flavi strains, mainly A. flavus, and their persistence during storage increase the chances of aflatoxin production on these substrates and indicates the need for good management practices to prevent mycotoxin contamination in Brazil nuts.

Aflatoxin and cyclopiazonic acid production by Queensland isolates of Aspergillus flavus and Aspergillus parasiticus

1989 ◽  
Vol 40 (2) ◽  
pp. 395 ◽  
Author(s):  
BJ Blaney ◽  
MA Kelly ◽  
AL Tyler ◽  
MD Connole
Keyword(s):  
Aspergillus Flavus ◽  
Acid Production ◽  
Aspergillus Parasiticus ◽  
Cyclopiazonic Acid ◽  
Aflatoxin Production ◽  
Quantitative Correlation ◽  
Low Concentrations ◽  
Maize Meal ◽  
High Concentrations ◽  
Relative Prevalence

The production of aflatoxins (AFB1, AFB2, AFG1, AFG2) and cyclopiazonic acid (CPA) by 50 Queensland isolates of thc Aspergillusflavus-Aspergillus parasiticus group was examined for the purposes of chemotaxonomy and toxicology. lsolatcs were cultured on Czapek Dox agar at 28�C and examined microscopically after 5, 7 and 10 days. Conidial heads were classified as either bearing phialides only or phialidcs and metulac, while conidia were classified according to degree of roughness. Isolates were also sown onto maize meal incubated at 28�C for 28 days and assayed for aflatoxins and CPA. A. flavus types were classified as having biseriate sterigmata in 40-100% of cases and slightly to moderately rough conidia, whereas A. paraszticus types were those with 0-35% biseriate sterigmata and spikey conidia. Of the 38 isolates classed as A. flavus, 34 produced CPA (range 1-70 mg kg-1). Three isolates produced neither aflatoxins (t0.02 mg kg-1) nor CPA (< 1 mg kg-1). Seven produced CPA but no aflatoxins. The remaining 28 isolates produced AFB1 (0.02-280 mg kg-1); seven of these produced low concentrations of AFG1(0.02-0.08 mg kg-1); and only one did not produce CPA. There was no quantitative correlation between CPA and aflatoxin production by the A. fIavus isolates. Of the 12 isolates classed as A. parasiticus, none produced CPA; all produced AFB1 (4-400 mg kg-1); all produced high concentrations of AFG1 (1-400 mg kg-1). The relative prevalence of the two fungi in Queensland is discussed as a guide to the likelihood of aflatoxin and CPA contamination of different agricultural commodities.

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