Zearalenone induced embryo and neurotoxicity in zebrafish model (Danio rerio): Role of oxidative stress revealed by a multi biomarker study.

In the present study, we evaluated the zearalenone induced adverse effects in zebrafish embryos using various endpoints like embryo toxicity, heart rate, oxidative stress indicators (reactive oxygen species (ROS), lipid peroxidation (LPO), Nitric oxide (NO)), antioxidant responses (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase enzyme (GST) and reduced glutathione (GSH), metabolic biomarkers (lactate dehydrogenase (LDH) and Nitric oxide (NO)), neurotoxicity (acetylcholinesterase (AChE)), genotoxicity (comet assay and acridine orange staining (AO)) and histological analysis. In this study, four concentrations 350, 550, 750 and 950 µg/L of ZEA were chosen based on LC10 and LC50 values of the previous report. The results shows that ZEA induces developmental defects like pericardial edema, hyperemia, yolk sac edema, spine curvature and reduction in heart rate from above 550 µg/L exposure and the severity was increased with concentration and time dependent manner. Significant induction in oxidative stress indices (ROS, LPO and NO), reduction in antioxidant defence system (SOD, CAT, GPx, GST and GSH) and changes in metabolic biomarkers (LDH and AP) were observed at higher ZEA exposed concentration. Neurotoxic effects of ZEA were observed with significant inhibition of AChE activity at higher exposure groups (750 and 950 µg/L). Moreover, we also noticed DNA damage, apoptosis and histological changes in the higher ZEA treatments at 96 h post fertilization (hpf) embryos. Hence, in the present study we concluded that oxidative stress is the main culprit in ZEA induced developmental, genotoxicity and neurotoxicity in zebrafish embryos.

Multiplex Detection of Fusarium Species.

Multiplex PCR is a powerful method to detect, identify, and quantify the mycotoxigenic fungus by targeting the amplification of genes associated with mycotoxin production and detection, identification, and quantification of Fusarium species. As compared with uniplex PCR, it has several advantages such as low cost, shortened time, and simultaneous amplification of more than two genes (in only one reaction tube). Here, we describe multiplex PCR-based detection and identification of trichothecene-, zearalenone-, fumonisin-, and enniatin-producing Fusarium species, the use of multiplex PCR in multiplex genotype assay and the use of multiplex TaqMan real-time qPCR.

Occurrence and molecular detection of toxigenic Aspergillus species in food grain samples from India.

BACKGROUND: The aim of this study was to detect the presence of different mycotoxigenic Aspergillus species in major food grains from southern states of India, namely maize, paddy, groundnut and sorghum. A total of 200 isolates recovered from 320 grain samples from four southern states were tested for their toxin chemotypes using high-performance liquid chromatography (HPLC), high-performance thin layer chromatography (HPTLC) and polymerase chain reaction (PCR) methods. The diversity and distribution of the isolates were recorded in terms of their frequency, density, importance value index and diversity indices. RESULTS: Among the different grain samples tested, 83% of groundnut, 69% of maize, 57% of sorghum and 29% of paddy samples had aflatoxin B1 (AFB1) levels above the allowed limit, while 82% of maize, 70% of sorghum, 42% of paddy and 17% of groundnut samples had ochratoxin A (OTA) concentrations higher than the permitted threshold (5 µg kg⁻¹). CONCLUSION: Since the southern states of India are temperate regions, environmental factors, especially temperature and relative humidity, may be responsible for the high levels of mycotoxins present in the grains studied. Therefore there is a need to generate awareness among farmers and consumers about the possible adverse health effects of high levels of mycotoxins present in different food grains.