RESUMEN
This study aimed to compare AFM1 occurrence in different cheese types produced by organic and conventional systems; and to evaluate the risk of food exposure to AFM1. A total of 176 commercial cheeses of 17 types were analyzed, 84 of organic and 92 of conventional production. Determination of AFM1 was performed by high- performance liquid chromatography (HPLC), being detected in 30.5% of samples, with 4.8% of organic cheese samples presenting quantifiable AFM1 values between 0.88 and 1.50 µg/kg. On the other hand, 4.3% of conventional cheese samples with values between 0.79 and 6.70 µg/kg. Two conventional cheese samples were above the limit of AFM1 allowed for cheeses by the Brazilian legislation. No statistical difference were found between organic and conventional cheeses regarding the occurrence (p = 0.1780) and concentration of AFM1 (p = 0.1810), according to the Chi-square and the T test, respectively. Estimated daily intake (EDI) and hazard index (HI) of dietary exposure to AFM1 were 0.26 ng/kg/day and 1.28 ng/kg/day, respectively, for conventional cheese samples, and 0.09 ng/kg/day and 0.47 ng/kg/day for organic samples, with no statistical difference for EDI (p = 0.1729) and HI (p = 0.1802) between the two production systems. Comparison between several cheese types from conventional and organic systems indicated that AFM1 is an obstacle to dairy production. Control and prevention of AFM1 contamination, as well as detoxification methods in the final products, are necessary. In the case of organic products, additional research is needed in order to determine which control and detoxification methods should be allowed in this production system.
Asunto(s)
Aflatoxina M1 , Queso , Contaminación de Alimentos , Aflatoxina M1/análisis , Contaminación de Alimentos/análisis , Humanos , Exposición Dietética , Brasil , Cromatografía Líquida de Alta PresiónRESUMEN
INTRODUCTION: Endometritis is a condition marked by inflammation of the endometrium that affects dairy cows from 21 days after parturition, causing damage to herd fertility and economic losses on farms. The use of active compounds obtained from plant sources has gained importance as disease treatment agents in farm animals due to the high resistance rates currently observed against traditional antibiotics commonly used. The study was carried out to examine the chemical composition and to investigate the antibacterial activity of rosemary, cinnamon, cloves, eucalyptus, lemon, oregano and thyme essential oils against the reference strain of Escherichia coli (ATCC 25922), Fusobacterium necrophorum (ATCC 25286), Trueperella pyogenes (ATCC 19411) and Staphylococcus aureus (ATCC 29213), considered as typical bacteria causing endometritis. METHODOLOGY: The chemical composition of the seven essential oils were analyzed by GC-MS and their antibacterial activity was evaluated by the disc diffusion method. RESULTS: Thirty-six components were identified in total using GC-MS analyzes. The main compounds were cinnamaldehyde (86.5% for cinnamon essential oil), eugenol (85.7% for clove essential oil), 1,8-cineol (80% for eucalyptus and 47.8% rosemary essential oils), limonene (65.5% for lemon essential oil), carvacrol (72.1% for oregano essential oil) and thymol (48.8% for thyme essential oil). The disc diffusion assay revealed that cinnamon, clove, oregano, and thyme essential oils showed the best results compared to the other three essential oils, showing the largest zone of inhibition against all bacteria evaluated. CONCLUSIONS: These findings indicated that essential oils are a potential agent to be used as an alternative for bovine endometritis treatment.
Asunto(s)
Infecciones Bacterianas/veterinaria , Enfermedades de los Bovinos/tratamiento farmacológico , Endometritis/veterinaria , Aceites Volátiles/química , Aceites Volátiles/farmacología , Actinomycetaceae/efectos de los fármacos , Animales , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Bovinos , Enfermedades de los Bovinos/microbiología , Endometritis/tratamiento farmacológico , Endometritis/microbiología , Escherichia coli/efectos de los fármacos , Femenino , Fusobacterium necrophorum/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Staphylococcus aureus/efectos de los fármacosRESUMEN
OBJECTIVE: Oropouche, Caraparu, Guama, Guaroa and Tacaiuma are ssRNA viruses that belong to the genus Orthobunyavirus and have been associated with human febrile illnesses and/or encephalitis. In this study, we evaluated the antiviral action of mycophenolic acid (MPA) on theseorthobunyaviruses to achieve a therapeutic agent to treat the diseases caused by these viruses. METHODS: The in vitro antiviral evaluation to MPA was done by using plaque assay at different periods of treatment. RESULTS: Results showed that MPA at a concentration of 10 microg/ml has significant antiviral activity on Tacaiuma virus when treatment was initiated either 24 h before or 2 h after viral infection. Moreover, MPA has an inhibitory effect on Guama virus replication, but only when treatment was initiated before cell infection. Addition of guanosine in the culture reverted the inhibitory effect of MPA on Tacaiuma and Guama viruses, suggesting that the antiviral activity of this substance was via depletion of the intracellular guanosine pool. CONCLUSION: Our results suggest that MPA would not be a good therapeutic agent to treat the diseases caused by Oropouche, Caraparu, Guama, Guaroa, and Tacaiuma viruses.
Asunto(s)
Antivirales/farmacología , Ácido Micofenólico/farmacología , Orthobunyavirus/efectos de los fármacos , Animales , Chlorocebus aethiops , Guanosina/metabolismo , Pruebas de Sensibilidad Microbiana , Factores de Tiempo , Células Vero , Ensayo de Placa Viral , Replicación Viral/efectos de los fármacosRESUMEN
Hantaviruses are the causative agents of severe human diseases such as Cardiopulmonary Syndrome (CPS), described for the first time in 1993. Approximately 200 cases of this emergent disease were reported in Brazil until August 2002, with a 40% fatality rate. In May 2001, a hantavirus serologic survey was carried out among 15-70-year-old inhabitants of Jardinopolis County, State of São Paulo, Brazil. Blood samples of 818 inhabitants from urban and rural areas were collected by digitopuncture and IgG antibodies, detected by an indirect enzyme-linked immunosorbent assay (ELISA) to the N recombinant protein of Andes hantavirus, were found in 14.3% of the samples, showing that this infection is common in Jardinopolis County, especially among adults irrespective of sex, profession, history of contact with rodents, or history of severe pneumonia. The results of the survey do not corroborate the idea that hantavirus infections are associated to rural activity and rodent contact, as observed with 20 Cardiopulmonary Syndrome cases occurred in the same region. Hantaviruses may be causing unrecognized infections, either asymptomatic or clinically nonspecific in addition to the syndrome. It may also be the case that more than one hantavirus type could be circulating in this region, causing mostly benign infections.