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BACKGROUND AND AIM: Broiler meat is susceptible to lipid oxidation due to its high content of unsaturated fatty acids, especially when stored for a long time. Concerning with that problem, we can add natural compounds to the animal feed, as the plant essential oils, which have antioxidant, antimicrobial, and antifungal activities. The objective of this study was to evaluate the antioxidant activity, fatty acid profile, and chemical composition of the meat of broilers fed with diets containing different essential oil, including lemongrass (Cymbopogon flexuosus) and pedestrian tea (Lippia aff. rotundifolia). MATERIALS AND METHODS: The experimental design used was a 4×4 factorial scheme (storage time×diets), and each treatment was repeated thrice. The treatments were applied as negative control (without antimicrobial); positive control (ration supplemented with 10 ppm of enramycin and 42 ppm of salinomycin), lemongrass (ration with 120 mg of essential oil of lemongrass for each kilogram of live weight of the animals), and pedestrian tea (ration with 120 mg of essential oil of pedestrian tea for each kilogram of live weight of the animals). Storage was performed after slaughter and evaluated monthly for 4 months. RESULTS: The inclusion of lemongrass oil and pedestrian tea in the broiler diet did not change the ether extract content of the meat sample obtained from thigh and drumstick. The storage time promotes an increase in the moisture loss of the meat from the 2nd month in all treatments. There was an interaction between the additive and storage time for moisture loss. In the 2nd month of storage, the meat from broilers fed the antibiotic-containing feed had a lower moisture loss than those from broilers in the other treatment groups. The fatty acid profile did not differ statistically between the different treatment groups. The inclusion of additives in the food dropped the lipid oxidation at the 2nd month of storage. From the 3rd month, however, only the essential oils showed antioxidant effect. CONCLUSION: Antioxidant activity was positive for treatments that included essential oils. The lemongrass oil and pedestrian tea can be used as antioxidant additives in broiler diets to improve the oxidative stability of thigh-drumstick meat during storage. The results of the study suggest a good prospective for further research with profitability of usage essentials oils examined, for their economical application as feed components in broiler nutrition.
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BACKGROUND AND AIM: The use of antimicrobials in the control of mastitis is of concern in public health due to their inefficiency in targeting microorganisms. Studies with medicinal plants have risen as an alternative to the use of conventional products. The objective of this study was to evaluate the efficacy of an experimental disinfectant based on the essential oil (EO) from Lippia origanoides in preventing the development of new intramammary infections (IMI) in Holstein cows. MATERIALS AND METHODS: The conventional protocol of pre- and post-milking was used and the control (Conventional treatment [CNV]) and experimental (Experimental treatment [PEX]) products containing EO at 120 µL/mL were applied by immersion. Individual milk samples were analyzed using sheep blood agar methodologies and biochemical tests. The efficiency of the treatment was defined by the presence or absence of Staphylococcus aureus, coagulase-negative Staphylococcus, and Streptococcus spp. RESULTS: There were no clinical and subclinical mastitis cases, no lesions in the mucosal of teats, nor dirt score between groups in this study. Both treatments did not influence the occurrence of IMI. CONCLUSION: The results revealed that PEX acts efficiently against microorganisms compared to the disinfection by the conventional product demonstrating the efficacy of the alternative product on the prevention of new IMIs in dairy cows.
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ABSTRACT: Studies about preservative and antioxidant activity of essential oils have been encouraged in recent years, given their importance to food industry. The aim of the current study was to evaluate the antioxidant properties and antimicrobial activity of essential oils deriving from Syzygium aromaticum, Cymbopogon citratus and Lippia alba against lactic and pathogenic bacteria responsible for food-borne diseases. Essential oil antibacterial activity was assessed through disc diffusion and macrodilution tests conducted in a mixed lactic culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus (YF-L903) and of Escherichia coli (ATCC 8739), Staphylococcus aureus (ATCC 6538), Salmonella enterica (ATCC 6017) strains. Based on the chromatographic analysis results, the essential oils shown to be composed of eugenol (79.41%) which was the prevalent compound in S. aromaticum, geranial (31.89%), neral (24.52%) and β-myrcene (25.37%) in C. citratus, as well as of geranial (33.80%) and neral (25.63%) in L. alba. The observed antibacterial activity confirmed the dose-dependent effect of these three oils on all the assessed bacteria; there was halo inhibition at concentration 20μL mL-1. The essential oil of S. aromaticum presented better antioxidant activity, with IC50 equal to 5.76μg mL-1 and antioxidant activity index of 6.94, and it was considered strong (AAI>2.0) in comparison to the other evaluated oils. This essential oil also presented excellent antioxidant activity at concentrations lower than the one required to inhibit lactic cultures. Based in this outcome, the essential oil from S. aromaticum can be used as preservative agent in processed food whose formulation presents lactic cultures.
RESUMO: A atividade conservante e antioxidante de óleos essenciais são importantes ferramentas para uso na indústria de alimentos e pesquisas são estimuladas na atualidade. O objetivo deste trabalho foi avaliar as propriedades antioxidantes e a atividade antimicrobiana de óleos essenciais de Syzygium aromaticum, Cymbopogon citratuse Lippia alba (LA) contra bactérias lácticas e patogênicas com importância em doenças transmitidas por alimentos. A atividade antibacteriana dos óleos foi avaliada por testes de disco-difusão e macrodiluição em caldo, utilizando-se cultura láctica mista de Lactobacillus delbrueckii subsp. bulgaricus e Streptococcus thermophilus (YF-L903), e Escherichia coli (ATCC 8739), Staphylococcus aureus (ATCC 6538), Salmonella enterica (ATCC 6017). Os compostos dos óleos essenciais foram identificados por cromatografia, mostrando eugenol (79,41%) como composto predominante em S. aromaticum, geranial (31,89%), neral (24,52%) e β-mirceno (25,37%) em C. citratus, e o geranial (33,80%) e neral (25,63%) em L. alba. A atividade antibacteriana confirmou o efeito dose-dependente dos três óleos para todas as bactérias avaliadas, apresentando halos de inibição a partir da concentração de 20μL mL-1. O óleo essencial de S. aromaticum apresentou melhor atividade antioxidante, com IC 50 IC50 (at concentration capable of generating 50% inhibition) igual a 5.76μg mL-1 e índice de atividade antioxidante (AAI) de 6,94, considerado forte (AAI>2,0) em relação aos demais óleos avaliados. O óleo essencial de S. aromaticum apresentou excelente atividade antioxidante em menor concentração que anecessário para inibir a cultura láctica, indicando que este óleo pode ser usado como conservante em alimentos processados contendo culturas lácticas.
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Objetivou-se determinar atividade antisséptica do óleo essencial de Lippia origanoides na presença de leite bovino. A composição química do óleo essencial de alecrim pimenta foi determinada por cromatografia gasosa acoplada à espectrometria de massas (CG-EM), sendo detectados 53 compostos, dos quais 16 foram identificados (>0,1% área total). O carvacrol (32,7%), p-cimeno (23%), timilmetil éter, cariofileno (7,98%) e o γ-terpineno (5,40%) foram os componentes mais abundantes. A concentração inibitória mínima para Staphylococcus aureus ATCC 25923 e E. coli ATCC 8739 foi de 60µL/mL, enquanto para Salmonella Choleraesuis ATCC 35640 foi de 90µL/mL. A concentração bactericida mínima foi de 120µL/mL para as três bactérias. Avaliou-se a atividade antisséptica do óleo essencial na concentração de 120µL/mL na presença de leite bovino sobre as mesmas cepas bacterianas. O óleo em estudo apresentou efeito inibitório do crescimento das cepas em diferentes tempos de ação (p<0,05). S. aureus apresentou maiores índices de inibição após 5 min de contato e Escherichia coli e Salmonella Choleraesuis após 15 min. O óleo essencial de alecrim-pimenta revelou ser um potencial antimicrobiano natural, mesmo na presença de matéria orgânica constituída de uma matriz nutricional complexa que é o leite bovino.(AU)
This study aimed to determine the antiseptic activity of the essential oil of Lippia origanoides in the presence of bovine milk. The essential oil chemical composition was determined by gas chromatography-mass spectrometry (CG EM) 53 compounds were detected, of which 16 were identified (>0.1% total area). The carvacrol (32.7%), p-cymene (23%), thymil methyl ether (10.03%), caryophyllene (7.98 %) and γ-terpinene (5.40%) were the most abundant components. The minimum inhibitory concentration for Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 8739 was 60uL/mL, as for this Salmonella Choleraesuis ATCC 35640 was 90uL/mL. The minimum bactericidal concentration was 120µL/mL for all three bacteria. We evaluated the antiseptic activity of the essential oil in the concentration of 120µL/mL in the presence of bovine milk for the same bacterial strains. The oil under study It showed an inhibitory effect of growth of the strains in different action times (p <0.05). S. aureus showed higher inhibition rates after 5 min of contact and E. coli and Salmonella Choleraesuis after 15 min. The essential oil Lippia origanoides proved to be a natural antimicrobial potential even in the presence of organic matter consists of a complex nutritional matrix is bovine milk.(AU)