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Effect of essential oils and extracts of Satureja macrosiphon and Satureja khozistanica on mycelial growth and aflatoxin B1 production in Aspergillus flavus
2015
Gorran, Akbar | Salehnia, Bentolhoda | Farzaneh, Hamid Reza | Farzaneh, Mohsen | Shivazad, Mahmoud
BACKGROUND: The hazardous nature of aflatoxins to human and animals necessitate the establishment of control measures. ObjectiveS: The effect of two medicinal plants, Satureja khozistanica and Satureja macrosiphon, was studied on inhibiting Aspergillus flavus growth and reducing aflatoxin B1-content in the liquid medium. Methods: Essential oils were isolated by hydrodistillation method, using a Clevenger-type apparatus. Various extracts of plant materials were macerated with various extraction solvents (ethanol, ethanol70% and water extracts). Essential oils (0, 62/5, 125, 250, 375 and 500 mg/l) and various extracts (0, 500, 1000, 2000, 4000 and 6000 mg/l) of S. khozistanica and S. macrosiphon were examined for reducing A. flavus growth and it’s AFB1-content in the liquid medium. Amount of aflatoxinB1 was evaluated by high performance thin layer chromatographymethod. Results: Essential oil of S. khozistanica at the concentration of 375 mg/l as well as its ethanol and ethanol 70% extracts at 4000 and 6000 mg/l respectively caused complete inhibition of fungus mycelial growth, whereas essential oil and extracts of S. macrosiphon couldn’t inhibit Aspergillus growth completely even at the maximum concentration. Essential oils of S. khozistanica and S. macrosiphonia at the concentration of 250 mg/l reduced AFB1-production 98 and 33.52% respectively. Various Extracts of S. khozistanica exhibited stronger anti-AFB1-biosyntesis activity than those of S. macrosiphon, so that, ethanol, ehanol70% and aqueous extracts of S. khozistanica at 4000 mg/l reduced 100, 96 and 32.37% of AFB1-production, respectively. On the contrary, essential oils, ethanol and ehanol70% extracts of both plants couldn’t significantly degrade AFB1-contamination, whereas aqueous extractsof S. khozistanica and S. macrosiphonia at the concentration of 4000 mg/l resulted in degradation of 25 and 32.16% AFB1-content, respectively. ConclusionS: In general, Essential oil and ethanol extract of S. khozistanica considerably inhibited A. flavus growth as well as AFB1-biosynthesis while aqueous extract of S. macrosiphon showed strong AFB1-degradation activity.
显示更多 [+] 显示较少 [-]Combined Effect of Atmospheric Cold Plasma and Zataria multiflora Essential Oil Boiss. on the Growth Inhibition of Aspergillus flavus in Iranian White Cheese and Evaluation of its Sensory Properties
2022
Raoofi Asl Soufiani, Mahdieh | Noori, Negin | Akhondzadeh Basti, Afshin | Gandomi Nasrabadi, Hassan | Ahari, Hamed | Khani, Mohammadreza
BACKGROUND: Cheese is recognized as a source of foodborne illness worldwide.OBJECTIVES: In this study, the growth inhibition of Aspergillus flavus inoculated on Iranian white cheese was investigated using cold atmospheric plasma and Zataria multiflora essential oil individually and in combination along with their effect on the sensory properties of cheese .METHODS: Slices of cheese cut in the presence and absence of 100 ppm of Zataria multiflora essential oil were exposed to cold atmospheric plasma for 2 and 5 minutes and stored in a refrigerator for 60 days. Afterwards, they were incubated in 5 time intervals (days 0, 15, 30, 45 and 60) and each was evaluated over a period of 10 days at 25 °C.RESULTS: Based on the results, the plasma inhibitory effect had a pattern dependent on the plasma flow time and the increase in the flow time reduced the radial growth rate of mold. At all times of plasma flow, a significant inhibitory effect was observed on the mold growth compared to the control group (P<0.05). In terms of growth inhibition percentage, the lowest inhibition was detected in the presence of essential oil alone and the highest inhibitory property resulted from 5 minutes of plasma flow with essential oil. There was no difference between the sensory properties of plasma-treated cheese and the essential oil in combination with those of plasma-treated samples alone. The findings also showed that the addition of essential oil had no effect on the sensory properties of cheese.CONCLUSIONS: Gliding arc plasma has inhibitory effects on the growth of Aspergillus flavus mold in cheese without adverse sensory changes, but the conditions must be optimized for industrial applications.
显示更多 [+] 显示较少 [-]Buffaloes (Bubalus bubalis) mycotic eye infection:
2021
Jenan Mahmood Khalaf | Abdulkarim Jafar Karim | Karima Akool Al Salihi
Buffaloes are one of the important farm animals in the south of Iraq and play an essential economical role mainly acting as dairy, meat, and draft animals. This study intended to diagnose buffalo mycotic eye infections in Thi-Qar province/Iraq. Some 250 buffaloes in the herd of 3,700 animals suffered from eye infections from December 2017 to November 2018. Eye swabs were collected from each infected eye of the affected buffaloes of both sexes before treatment. The animals were in different age groups. All samples were transferred to the laboratory in transfer media, and cultured on Sabouraud dextrose (SDA) agar with and without 0.05 g/mL and 0.4 g/mL chloramphenicol and cycloheximide, respectively. Later, the agars were incubated at 25o C and 37o C. The total percentage of eye infection was (6.75%), constituting (49.2%) mycotic infections. The predominant clinical manifestations that appeared on the infected buffaloes were eye inflammation represented by congestion, lacrimation, the opacity of cornea and edema, and reduced productivity of the infected animals. Different fungal isolates were identified from the samples including Aspergillus fumigates, Aspergillus flavus, Aspergillus niger, Penicillium spp., Alternaria spp., Fusarium spp., Candida spp., Cladosporium spp., Rhodotorula spp., Mucor spp. and Rhizopus spp. Calves buffaloes below one-year-old were more prone to mycotic infection than one-year-old or more. Additionally, male buffaloes were more susceptible to infection than females. In conclusion, this study isolated various types of fungus from the inflamed eyes of buffaloes. Fungal eye infection and the potential risk factors for fungal keratitis in buffaloes were also investigated. The study also approved the rapid diagnosis of fungi by direct microscopic detection and culture. The author recommends future studies including large numbers of the buffalo herd in Iraq to determine the epidemiology of this condition in the country.
显示更多 [+] 显示较少 [-]Aspergillosis in domestic and wild birds from Argentina
2019
Romina Della Vedova | Alejandra Hevia | Walter Vivot | Julián Fernández | Susana Beatriz Córdoba | Francisco José Reynaldi
Aspergillus species are widely distributed throughout the world and can develop parasitic and saprophytic ways of life, allowing Aspergillus to infect living hosts, including plants, insects, birds and mammals. The most common form of aspergillosis in poultry and other birds is respiratory infection. Clinical manifestations depend on the infective dose, pre-existing diseases, and the immune response of the host. The aim of the present research was to study aspergillosis in domestic and wild birds from Argentina. We carried out morphological and molecular identification, and determination of antifungal susceptibility against seven antifungal drugs. Six birds from different cities of Buenos Aires Province of Argentina were studied. Three of the samples belonged to broiler chicks, while the other three belonged to an eagle, a pheasant, and a kelp gull. Two isolates were identified as Aspergillus fumigatus by morphological characteristics and growth at 50 °C. Morphology and BenA sequencing enabled us to identify three isolates as Aspergillus flavus, and one as Aspergillus sydowii. All antifungal drugs tested showed low MIC values, ranging from 0.008 to 1 mg/L. Aspergillosis in birds causes high economic losses and could be controlled by sanitation, avoidance of moldy food, nest and litter and reducing stress factors.
显示更多 [+] 显示较少 [-]Packaging fortified with Natamycin nanoparticles for hindering the growth of toxigenic Aspergillus flavus and aflatoxin production in Romy cheese
2021
Asmaa Fayed | Huda Elsayed | Taghreed Ali
Objective: This study assessed the effect of cellulose sheets fortified with Natamycin-loaded algi¬nate nanoparticles on the growth of toxigenic Aspergillus flavus and aflatoxin production on the superficial layer of Egyptian Romy cheese after 12 weeks of maturation. Materials and Methods: Toxigenic A. flavus (GenBank accession No. MT645073) was inoculated into the outer surface of Egyptian Romy cheese (at 5 log CFU/gm) and wrapped with a cellulose sheet fortified with Natamycin-loaded alginate nanoparticles. Unwrapped control contaminated Romy wheels were made as well as non-contaminated wrapped cheese wheels for sensory eval¬uation. Romy cheese wheels were stored at a temperature similar to commercial methods for 12 weeks. Fungal counts were enumerated during this time, and enzyme-linked immune sorbent assay detected aflatoxin after the 4th week of maturation storage. Results: In cheese samples covered with cellulose sheets containing Natamycin-loaded alginate nanoparticles, the fungal count was reduced by 2 log approximately in contrast to control samples after the 2nd week of storage. However, within the 8th week of storage, the greatest significant reduction (p < 0.05) was seen where fungal growth was hindered entirely to the end of the rip¬ening period. The mean values for taste, color, flavor, and overall acceptability were 4, 4.7, 4.09, and 4.3, respectively. Furthermore, in the treated samples, the total aflatoxin concentration was decreased by 78.6% relative to the untreated control one. Conclusion: Using cellulose sheets fortified with Natamycin-loaded alginate nanoparticles in Egyptian Romy cheese wrapping could be an effective way of controlling A. flavus and subsequent aflatoxin production without influencing the typical taste, color, flavor, and overall appearance of traditional Romy cheese. [J Adv Vet Anim Res 2021; 8(1.000): 58-63]
显示更多 [+] 显示较少 [-]Prevalence and Mycotoxigenic Potential of Fungi in Fish Feed Collected from Fish Farms in Egypt with a Particular Reference to Aflatoxins Contamination
2024
Yasmen Galal | Magdy El-Bana | Mohamed M. Deabes | Abdel-Hamied M. Rasmey
The current study is aimed to investigate the fungal contaminants in fish feed. Isolation of fungi was conducted on modified dichloran 18% glycerol agar (DG18) and potato dextrose agar (PDA). Feed samples were assayed for aflatoxins using HPLC. A total of 43 species belonging to 19 fungal genera recovered from 45 fish feed samples. Aspergillus and Penicillium were the most predominant genera with isolation frequency values indicated the retrieval capability of DG18 over PDA medium. For instance, Aspergillus spp. recorded 60%, 53.3% while Penicillium spp. were 33.3%, 17.8% on DG18 and PDA respectively via direct plating. 41.4% of the tested isolates were mycotoxin producers. Aflatoxins B1, B2, G1 and G2 were detected by 6 out of 10 screened Aspergillus isolates. Fumitremorgens, Gliotoxin, Ochratoxin A and B, and Zeralenone were also detected. The feed samples of high total count percentages (TC%) of A. flavus recorded the highest incidence of aflatoxins B2, G1 and G2 (2.3, 35.3 and 7.8 ng/g respectively). Meanwhile, the highest B1 concentration (3.7 ng/g) was recorded for the highest TC% interval studied (1:9 cfu/g). Thus, it is important to monitor the fungal load and mycotoxins in fish feed periodically using proper practical approaches.
显示更多 [+] 显示较少 [-]Prevention of aflatoxicosis by addition of hydrated sodium calcium aluminosilicate to the diets of growing barrows
1989
Harvey, R.B. | Kubena, L.F. | Phillips, T.D. | Huff, W.E. | Corrier, D.E.
Hydrated sodium calcium aluminosilicate (HSCAS), an anticaking agent for mixed feed, was added to the diets of growing barrows and was evaluated for its potential to ameliorate the clinical signs of aflatoxicosis. The experimental design consisted of 6 treatments of 5 barrows each at concentrations of 0 g of HSCAS and 0 g of aflatoxin (AF)/kg of feed (control), 5 g of HSCA/kg of feed (0.5%), 20 g of HSCAS/kg of feed (2.0%), 3 mg of AF/kg of feed, 5 g of HSCAS (0.5%) plus 3 mg of AF/kg of feed, or 20 g of HSCAS (2.0%) plus 3 mg of AF/kg of feed. Barrows were maintained in indoor concrete-floored pens, with feed and water available ad libitum for 28 days (from the age of 7 to 11 weeks). Barrows were observed twice daily and were weighed weekly, and blood samples were obtained weekly for hematologic and serum biochemical measurements. At the termination of the study, barrows were euthanatized and necropsied. Body weight gains were diminished significantly (P less than 0.05) by consumption of 3 mg of AF/kg of feed, whereas body weight gain in barrows consuming diets containing HSCAS or HSCAS plus AF did not differ from that in control barrows. Serum enzymatic activities of alkaline phosphatase and gamma-glutamyl transferase and prothrombin time were increased in barrows consuming 3 mg of AF/kg of feed, but not in those consuming HSCAS or HSCAS plus AF. Aflatoxin alone induced decreased serum concentrations of urea nitrogen, albumin, total protein, calcium, phosphorus, cholesterol, and glucose, as well as serum total iron-binding capacity, whereas HSCAS or HSCAS plus AF did not induce such effects. Liver weight was increased in barrows of the AF-alone treatment group, compared with control barrows. Hepatic lesions in barrows of the AF-alone treatment group were charaterized as peripheral lobular lipidosis accompanied by periportal and interlobular fibrosis and bile duct hyperplasia. Hepatic lesions were not observed in barrows of the 0.5% HSCAS plus AF or 2.0% HSCAS plus AF treatment groups. These findings suggested that HSCAS can modulate the toxicity of AF in growing barrows (perhaps via sequestration and reduced bioavailability in vivo) and may offer a novel approach to the preventive management of aflatoxicosis in animals.
显示更多 [+] 显示较少 [-]Interaction of strains of non-toxigenic Aspergillus flavus with Aspergillus parasiticus on aflatoxin production | Interacções de estirpes de Aspergillus flavus não-toxígenas com Aspergillus parasiticus na produção de aflatoxinas
2000
Hermínia Marina Martins | Maria Lígia Martins | Fernando Almeida Bernardo
Aflatoxins production is affected by abiotic, biotic and genetic parameters. Eugenesic and dysgenetic condition for aflatoxinogenesis are relatively well studied, such as: the influence of temperature, pH, Aw, Oxigen tension, osmotic pression, organic and inorganic nutrients, substance with fungistatic effects: however there are relatively few knowledge about endogenous regulator mechanisms, the kinetic of the anabolism and the interaction between the productive moulds and remaining microflora holding in eutrophying substrates. The main objective of this study is to evaluate biotic interaction between five indigenous strains of A. flavus, confirmed non-toxigenic, and a productive strain (A. parasiticus ATCC 15 517), cultured simultaneously on two substrates: one natural (cracked corn) and a synthetic one, modified Czapeck-Dox broth. Aflatoxins quantifications were performed by HPLC at 8th and 12th days. Results of those interactive cultures showed that all strains were synergic, increasing aflatoxins production in a range between 5.6 and 106.5% over the control values, with an exception registered on one of the strains cultured in cracked corn at the 12th day, where the production decreased (-7.6%). | A produção de aflatoxinas é afetada por parâmetros abióticos, bióticos e genéticos. As condições eugenésicas e disgenésicas da aflatoxinogênese estão relativamente bem estudadas, tal como as influências ecológicas (temperatura, pH, Aw, tensão de oxigênio, pressão osmótica, nutrientes e substâncias fungistáticas). Contudo, é muito escasso o conhecimento relativo aos mecanismos reguladores endógenos, à cinética do anabolismo e à interação dos fungos produtores com a restante microflora presente em substratos eutrofizantes. O principal objetivo deste estudo é avaliar a interação de cinco estirpes indígenas de A. flavus, comprovadamente atoxígenas, com uma geneticamente apta (A. parasiticus ATCC 15517), cultivadas simultaneamente em dois substratos: um natural (milho triturado) e outro sintético (Caldo de Czapeck-Dox Modificado). A quantificação das aflatoxinas foi efetuada no 8º e 12º dias de incubação, por Cromatografia Líquida de Alta Resolução (HPLC). Os resultados demonstraram que todas as estirpes foram sinérgicas, aumentando o rendimento da produção entre 5,6 e 106,5%, quando comparados com os valores das testemunhas.
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