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Aflatoxin M1 is a derivate of aflatoxin B1 and an important contaminant of milk and dairy products. This systematic review and meta-analysis was conducted on relevant Persian and English original articles in national and international databases with no time limits until 1 January 2018. In total 605 articles were found among which 70 articles met the inclusion criteria for meta-analysis. The prevalence (95% confidence interval (CI)) and mean concentration (95% CI) of aflatoxin M1 was found to be 64% (53-75%) and 39.7 ng/l (31.9-47.4 ng/l) in raw milk, 95% (89-98%) and 62.3 ng/l (40.6-84 ng/l) in pasteurised milk, 71% (56-84%) and 60.1 ng/l (30.9-89.3 ng/l) in sterilised milk, 59% (20-93%) and 5.5 ng/l (3.3-7.7 ng/l) in breast milk and 72% (61-81%) and 82.3 ng/kg (63.7-100.9 ng/kg) in dairy products. In general, 9% (4-16%) of milks and 10% (4-17%) of dairy products had aflatoxin M1 in concentrations exceeding the permitted level of Iranian standards (500 ng/l). Based on the maximum permitted aflatoxin M1 concentration in standards of Europe (50 ng/l), these percentages increase to 25% (18-32%) for milks and 18% (9-29%) for dairy products. According to the results, further control and preventive measures should be applied on livestock feeds because decreased aflatoxin B1 contamination at this level results in decreased aflatoxin M1 in milk and dairy products.

Aspergillus parasiticus is one of the most common fungi able to produce aflatoxins, which are naturally occurring carcinogenic substances. This study evaluated the effects of the safe yeast, Kluyveromyces lactis, on fungal growth, aflatoxin production and expression of aflR gene in A. parasiticus. Antifungal susceptibility was evaluated by exposing A. parasiticus to different amounts of K. lactis, and aflatoxin production was measured using high-performance liquid chromatography. Expression of the aflR gene was determined by measuring the cognate aflR mRNA level by quantitative real-time reverse-transcription polymerase chain reaction assay. The growth of A. parasiticus was inhibited by 7 days of incubation at 30°C with a minimum population of 1.5 × 105 CFU/ml of K. lactis, which also suppressed expression of the A. parasiticus aflR gene, reducing the total production of aflatoxins by 97.9% and aflatoxins B1, B2, G1 and G2 by 97.8, 98.6, 98 and 94%, respectively. Accordingly, K. lactis could be considered as a potential biocontrol agent against toxigenic molds in food and animal feed.

The enzyme β-glucanase was extracted from Trichoderma reesei in bovine rumen fluid samples collected from a slaughterhouse and its effect was investigated in broilers. Data collected was broiler performance, carcass characteristics, duodenum microbial flora, hematological, and immunological parameters. β-glucanase activity was assayed through spectrometry and was approximately 0.434 IU per gram culture medium. In the current study, endoglucanase enzymes were extracted from Trichoderma reesei. A total of 160 local broilers (Golpayegan-Ross hybrid) were allocated to 4 treatments with 4 replicates per treatment. Over a 49-day experimental period, broilers were fed a basal diet (T1), basal diet plus 20% barley (T2), basal diet with 10 IU extracted β-glucanase and 20% barley (T3), and basal diet with 10 IU commercial β-glucanase and 20% barley (T4). The T3 treatment resulted in the greatest body weight gain at the end of experiment (P 0.01). No significant differences were for feed conversion (FCR; P 0.05). The highest cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), and LDL cholesterol ratio was observed in the T3 treatment. The highest concentrations of immunoglobulin G1 (IgG1), immunoglobulin G2 (IgG2), and immunoglobulin M1 (IgM1) were observed in the T4 treatment. The T3 treatment resulted in the best response for all measured carcass characteristics. The highest levels of aerobic bacteria, lactobacilli, anaerobic bacteria, and E. coli were associated with the T4, T3, T4, and T1 treatments, respectively. It is concluded that β-glucanase supplementation can be used to overcome the anti-nutritive effects of water soluble barley non-starch polysaccharides (NSPs) and consequently enhance broiler performance without any adverse effects on humoral immunity parameters.

Recent studies indicated the inhibitory effects of lactic acid bacteria (LAB) strains isolated from different origins on both fungal growth and aflatoxin production. This study aimed to investigate the inhibitory effect of Lactobacillus plantarum and L. delbrueckii subsp. Lactis on Aspergillus parasiticus ATCC15517 growth. Quantification of aflatoxin was performed using high-performance liquid chromatography technique. Quantitative changes in the expression of the aflR gene were analyzed by measuring the cognate aflR mRNA level with quantitative real-time reverse-transcription polymerase chain reaction. Our results demonstrated the inhibitory effect of LAB on A. parasiticus growth at 2 × 103 cfu/ml of L. plantarum and L. delbrueckii subsp. Lactis. Aflatoxin G2 production was significantly inhibited to lower than level of detection. The level of aflR gene expression was considerably decreased after the exposure of fungal cells with used LABs. Assessment of the used LABs on A. parasiticus revealed antifungal properties and effective ability to decrease aflatoxin production. Practical applications Fungi spoilage is widespread among different types of food that may result in huge amounts of waste and economical lost. In addition, side effects raised by using chemical additives as preservative, are a serious source of health concern. Therefore, natural agents such as lactic acid bacteria which are also commonly used as probiotics in recent years, could play a good role as inhibitors of fungal growth as well as mycotoxin production both in food and feed. Different media like dairy foods and so on, can be formulated with Lactobacillus plantarum and L. delbrueckii subsp. Lactis, to prevent Aspergillus parasiticus growth and mycotoxin excretion. LAB can be added to processed food during inoculation step and even for protection, they can be capsulated with edible materials to improve their efficiency.

Recent investigations revealed the effects of herbal extracts on both fungal growth as well as aflatoxins production. In the present study, we tried to evaluate antifungal activity as well as antitoxin activity of Glycyrrhiza glabra (licorice) extract. Strain American Type Culture Collection 15517 of Aspergillus parasiticus was used to perform antifungal susceptibility test according to Clinical and Laboratory Standards Institute document M27-A3, and the rate of aflatoxin production was determined using high-performance liquid chromatography technique after exposure to different concentrations of licorice extract. Quantitative changes in the expression of the aflR gene were analyzed by measuring the cognate aflR mRNA level with quantitative real-time reverse-transcription polymerase chain reaction assay. Our obtained results demonstrated the inhibitory effect of licorice extract on Aspergillus parasiticus growth at 500 mg/mL of licorice extract. In addition, a significant decrease in aflatoxin production was revealed at the same concentration. However, the production of aflatoxin B1 was entirely inhibited in 10 g/mL of licorice extract. The level of aflR gene expression was significantly decreased after the exposure of fungal cells to 500 g/mL of licorice extract. Evaluation of the antifungal and antitoxin activity of licorice extract on Aspergillus parasiticus revealed its antifungal properties as well as its effective ability to decrease aflatoxin production. Practical Application Several classes of synthetic antifungal drugs are used today to treat fungal infections in humans and crops. However, this antifungal therapy is not always effective because of emerging of drug-resistant strains. Therefore, using effective natural antifungal agents with fewer side effects is a promising approach to combat fungal diseases either in medicine or in agriculture. In the present study, we introduced the licorice extract as a novel natural compound to inhibit the growth and production of aflatoxin in the filamentous fungi Aspergillus parasiticus and evaluated this natural herbal extract as an antifungal agent.

Background: Aflatoxins are highly toxic secondary metabolites mainly produced by Aspergillus parasiticus. This species can contaminate a wide range of agricultural commodities, including cereals, peanuts, and crops in the field. In recent years, research on medicinal herbs, such as Pistacia atlantica subsp. kurdica, have led to reduced microbial growth, and these herbs also have a particular effect on the production of aflatoxins as carcinogenic compounds. Objectives: In this study, we to examine P. atlantica subsp. kurdica as a natural compound used to inhibit the growth of A. parasiticus and to act as an anti-mycotoxin. Materials and Methods: In vitro antifungal susceptibility testing of P. atlantica subsp. kurdica for A. parasiticus was performed according to CLSI document M38-A2. The rate of aflatoxin production was determined using the HPLC technique after exposure to different concentrations (62.5 - 125 mg/mL) of the gum. The changes in expression levels of the aflR gene were analyzed with a quantitative real-time PCR assay. Results: The results showed that P. atlantica subsp. kurdica can inhibit A. parasiticus growth at a concentration of 125 mg/mL. HPLC results revealed a significant decrease in aflatoxin production with 125 mg/mL of P. atlantica subsp. kurdica, and AFL-B1 production was entirely inhibited. Based on quantitative real-time PCR results, the rate of aflR gene expression was significantly decreased after treatment with P. atlantica subsp. kurdica. Conclusions: Pistacia atlantica subsp. kurdica has anti-toxic properties in addition to an inhibitory effect on A. parasiticus growth, and is able to decrease aflatoxin production effectively in a dose-dependent manner. Therefore, this herbal extract maybe considered a potential anti-mycotoxin agent in medicine or industrial agriculture.