Phytoprevention of aflatoxin production

Consumption of mycotoxic foods is associated with several cases of human poisoning, or mycotoxicosis, sometimes resulting in death. Phytopreventive inhibition of Aspergillus parasiticus growth and its aflatoxin production by the essential oils extracted from Thymus kotschyanus Boiss and Hohen and Zataria multiflora Boiss. is reported in this study. Minimal inhibitory concentration [MIC], minimal fungicidal concentration [MFC] and fungicidal kinetics of the oils were determined and compared with each other. The oils from the above mentioned plants were found to be strongly fungicidal and inhibitory to aflatoxin production. Both oils inhibited aflatoxin B[1] [AFB[1]] production by A.parasiticus. T. kotschyanus and Z. multiflora oils at 25 ppm concentration, reduced AFB1 levels by 100% and 47.87% respectively. Aflatoxin production was significantly inhibited at lower than fungistatic concentration of both oils. The analysis of oils by GC and GC/MS led to identification of 27 and 22 components in T. kotschyanus and Z. multiflora Boiss. respectively which were very similar to each other. Prevention of fungal growth and aflatoxin production by natural compounds is recom

[Cyclooxygenase; prevention and treatment]

Cyclooxygenase [COX] is the key enzyme required for the conversion of arachidonic acid to prostaglandins. Two cycloxygenase isoforms have been identified and are referred to as COX-I and COX-2. Both enzymes are blocked by nonselective anti-inflammatory drugs [NSAID], such as indomethacin and ibuprofen. COX-I is an enzyme normally found in tissues and is involved in physiological functions, while COX-2 is an acute phase reactant associated with inflammation. Recently, COX-2 has been found to be associated with hyperalgesia, angiogenesis, cancer and Alzheimers disease. The suggestion that COX-2 is causally linked to cancer offers a new approach to extending our knowledge about the neoplastic phenomenon and improving management of human malignant diseases

Effect of sound conditioning on protection of hearing and plasma antioxidant activity in rabbits

Noise is one of the major physical pollutants in present societies. Sound conditioning is used as means of protecting against noise-induced hearing loss. The status of plasma antioxidant system during sound conditioning is important. To study possible involvement of plasma total antioxidant ability in noise-induced hearing loss and sound conditioning. This study was carried out on 24 male white New Zealand rabbits [6 in each group]. The rabbits were assigned to the following four groups: [1] Noise exposure [250Hz-20000Hz, 110 dB for 8h/day for 12 days], [2] Conditioning noise exposure [80dB for 10 days and 110 dB for 12 days], [3] Noise exposure [80 dB] and [4] control group. Auditory Brain stem Response [ABR] was measured and compared in all pre- and post-exposures groups. Plasma antioxidant power was also measured post exposure. FRAP was assayed in plasma sample collected from each animal using TPTZ reagent. The ABR assay using click in different experimental groups showed that the absolute latency of 5[th] wave generation was statistically significant in first group as compared to other groups [p=0.0001]. Likewise ABR assay using tone burst showed a higher absolute latency observed in group 1. FRAP assay indicated that the antioxidant parameters were suppressed in group 1 when compared with data obtained from other groups [p<0.05]. The ABR results found in our study, confirmed sound conditioning in rabbits exposed to 80 and 110 dB. Furthermore, changes in FRAP in rabbits studied in our experiment was indicative of involvement of antioxidant system in sound conditioning however, further studies needed

pathological study of hepatic lesions after experimental aflatoxicosis in broiler chickens

To study gross and histopathologic lesions and also relative weight of liver in experimental aflatoxicosis in Ross broiler chicks. Experimental study. Two hundred and forty 1-day-old Ross broiler chicken. Linear model analysis and Duncan's method for mean values with S AS package. The chickens were fed by NRC [1994] diet. Feed and water were provided ad libitum. The diets were divided into 3 groups: control [0 or basal] and treatment with 1 and 2 ppm of aflatoxin. Aflatoxin was produced by infecting of autoclaved rice with Aspergillus parasiticus NRRL-2999 in the flasks and titrated by TLC and HPLC. After 21 and 42 days, three chickens from each group randomly killed and their livers were weighed. Tissue samples were collected and fixed in 10% neutral buffered formalin, embedded in paraffin, sectioned at 5 um and stained by haematoxylin and eosin [H and E]. Relative weights of the livers [g/l00g.b.w] in treatment groups were significantly increased as compared with control [p<0.05]. Histopathologic examination revealed severe fatty change, regeneration foci of liver cells, fibrosis of portal regions and bile ductule hyperplasia. The lesions were very severe in 42-days-old chickens and had the lesser severity in 21-days-old chickens. Liver is the target organ for aflatoxin. Aflatoxin causes severe lesions in the liver and increases its relative weight.Prolonged exposure to low concentrations of toxin produces severe changes in fat metabolism and bile ductules proliferation