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This study aimed to assess the efficacy of a multi-hurdle process combining mild High Hydrostatic Pressure (HHP) treatments and Thyme Oil (TO) edible films as a non-thermal method to combat pathogenic E. coli (aEPEC and STEC) in raw cow's-milk cheese stored at 7 °C and packaged under modified atmosphere. Changes in headspace atmosphere of cheese packs and treatment effects on Lactic Acid Bacteria (LAB) counts and diarrheagenic E. coli strains (aEPEC and STEC) were evaluated over a 28 d storage period. The results demonstrated that the combined treatment exhibited the most significant antimicrobial effect against both strains compared to individual treatments, achieving reductions of 4.30 and 4.80 log cfu/g after 28 d of storage for aEPEC and STEC, respectively. Notably, the synergistic effect of the combination treatment resulted in the complete inactivation of intact cells for STEC and nearly completed inactivation for aEPEC by the end of the storage period. These findings suggest that the combination of HHP with selected hurdles could effectively enhance microbial inactivation capacity, offering promising alternatives for improving cheese safety without affecting the starter microbiota.

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Essential oils (EOs), as rumen additives, decreased CH4 emissions in in vitro trials but results from in vivo studies are still limited. We investigated the effects of Origanum vulgare (OEO) and Thymus vulgaris (TEO) EOs on in vivo methane emissions from Nellore beef cattle. Six adult rumen-cannulated Nellore cattle were used in a double 3 × 3 Latin square design. Treatments consisted of three diets containing either 3 mL OEO per kg of concentrate, 3 mL TEO/kg of concentrate, or no EO addition. The experimental period consisted of three 21 d feeding periods and methane production was measured using the sulfur hexafluoride (SF6) technique from Day 16 to Day 21 of each feeding period. Intake, total apparent digestibility (dry matter as well as neutral and acid detergent fiber), and rumen parameters (pH, ammoniacal nitrogen concentration, and short-chain fatty acids) were also evaluated. The EOs did not decrease CH4 emissions and had no effect on rumen parameters.

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This study aimed to assess the effect of combining amitraz with essential oils (EOs) from Thymus vulgaris and Lippia sidoides, as well as the monoterpenes thymol and thymol acetate, on Rhipicephalus microplus in laboratory conditions, and to select the most effective combination for testing in field conditions. The chemical analysis showed that EOs were mainly composed of monoterpenes, with thymol and p-cymene as the major compounds. In larval (LIT) and adult (AIT) immersion tests using different concentrations of the oils and terpenes mixed with amitraz, the results showed that both EOs and thymol improved the efficacy of amitraz against larvae and engorged females of R. microplus, whereas thymol acetate only enhanced activity against larvae. The most favorable outcome was obtained with the EO of L. sidoides combined with amitraz, resulting in 99 % and 100 % efficacy against larvae and engorged females, respectively. Furthermore, the combination of amitraz with thymol showed presented an efficacy of 94 % and 91 % against larvae and engorged females, respectively. Thus, for the other tests, the combination of thymol + amitraz was chosen due to the ease of working with pure thymol in bioassays, and easier standardization. The immersion test (thymol + amitraz) with semi-engorged females showed 100 % efficacy for the combination of thymol + amitraz, while in tests with different solvents (thymol + amitraz), ethanol being the most effective solvent among those tested (ethanol, Triton, and Tween), resulting in 95 % efficacy on engorged females. In the field test, in treatments with amitraz and thymol + amitraz, efficacy of 54 % and 74 % was observed on day + 3 and 33 % and 43 % on day + 7, respectively. Assessing the reproductive biology of females recovered from animals treated with amitraz or amitraz + thymol, in day + 7, efficacies of 33 % and 52 %, respectively, were observed. EOs from T. vulgaris and L. sidoides and thymol improved the acaricidal activity of amitraz on larvae and engorged females of R. microplus under laboratory conditions, while thymol acetate only enhanced activity against larvae. Thymol increased the efficacy of amitraz under field conditions, however for the development of a commercially available acaricide to R. microplus control, additional studies are needed to increase the efficacy. Further research is needed (by changing concentrations, adding other compounds and/or developing formulations) to increase acaricidal efficacy and develop new effective products to combat R. microplus infestations in cattle.

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Increased antibiotic resistance presents a health problem worldwide. The World Health Organization published a list of pathogens considered a priority for designing new treatments. Klebsiella pneumoniae (Kp) is a top-priority microorganism, highlighting the strains that produce carbapenemases. Developing new efficient therapies or complementing existing treatments is a priority, and essential oils (EOs) provide an alternative. EOs could act as antibiotic adjuvants and enhance antibiotic activity. Employing standard methodologies, the antibacterial activity of the EOs and their synergic effect with antibiotics were detected. A string test was used to identify the impact of the EOs over the hypermucoviscosity phenotype presented by Kp strains, and Gas Chromatography-Mass Spectrometry analysis identified EOs and the composition of EOs. The potential of EOs for designing synergistic therapies with antibiotics to combat the infection of KPC diseases was demonstrated. In addition, the alteration of the hypermucoviscosity phenotype was shown as the principal mechanism of a synergic action between EOs and antibiotics. The differential composition of the EOs lets us identify some molecules that will be analyzed. Synergic activity of EOs and antibiotics can provide a solid platform for combating multiresistant pathogens that represent a severe health sector problem, such as Kp infections.

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Plants are sessile, and their ability to reprogram their metabolism to adapt to fluctuations in soil water level is crucial but not clearly understood. A study was performed to determine alterations in intermediate metabolites involved in central carbon metabolism (CCM) following exposure of Mexican mint (Plectranthus amboinicus) to varying watering regimes. The water treatments were regular watering (RW), drought (DR), flooding (FL), and resumption of regular watering after flooding (DHFL) or after drought (RH). Leaf cluster formation and leaf greening were swift following the resumption of regular watering. A total of 68 key metabolites from the CCM routes were found to be significantly (p < 0.01) impacted by water stress. Calvin cycle metabolites in FL plants, glycolytic metabolites in DR plants, total tricarboxylic acid (TCA) cycle metabolites in DR and DHFL plants, and nucleotide biosynthetic molecules in FL and RH plants were significantly (p < 0.05) increased. Pentose phosphate pathway (PPP) metabolites were equally high in all the plants except DR plants. Total Calvin cycle metabolites had a significantly (p < 0.001) strong positive association with TCA cycle (r = 0.81) and PPP (r = 0.75) metabolites. Total PPP metabolites had a moderately positive association with total TCA cycle metabolites (r = 0.68; p < 0.01) and a negative correlation with total glycolytic metabolites (r = -0.70; p < 0.005). In conclusion, the metabolic alterations of Mexican mint plants under different watering regimes were revealed. Future studies will use transcriptomic and proteomic approaches to identify genes and proteins that regulate the CCM route.

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A total of 500, 14-d old male Ross 308 broilers were allocated into five treatments (4 replicates each) including: a negative (NC) and positive control diet (PC) which supplemented without and with 7% poultry by-product meal (PBPM), respectively and three levels of additive supplementation of thyme and rosemary powders in the basal diets: 0.750% rosemary powder (PCR); 0.375% thyme powder + 0.375% rosemary powder (PCRT), and 0.750% thyme powder (PCT) rosemary powder. The PCRT diet improved (p<0.05) average daily gain and feed conversion ratio by 5.62 and 10.37% compared to PC, respectively. The serum concentration of lipids (triglycerides, cholesterol, high-density lipoprotein, and low-density lipoprotein) was decreased while the ilealvillus heightand ratio of villus height to crypt depth as well as ileal microbiota population were improved(p<0.05) in response to inclusion PCRT diet compared to PC diet. The blood serum concentration of malondialdehyde was statistically decreased (p<0.05) by supplementation of PCRT in broiler diets. Our results suggested that supplementation of a blend of thyme and rosemary powders at the level of 0.375% of each into broiler diet during d 14-42 has merit to be used as a natural antioxidant in diets formulated by PBPM.(AU)

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Hass avocadoes are one of the most popular fruits consumed worldwide because of their nutritional and nutraceutical content. Nevertheless, these fruits are susceptible to phytopathogen attacks that decrease fruit quality during the postharvest period. Herein we present the results of the in situ fungistatic activity of four hybrid films (FT1−FT4) manufactured with chitosan and different concentrations of the essential oil of thyme (TvEO). The films were evaluated as biodegradable materials to prevent fruit decay triggered by Clonostachys rosea which is considered an emergent phytopathogen of this crop. The in situ fungistatic strength, spectroscopic properties (FT-IR), optical features (transmittance/opacity), and consistency obtained by microscopic analysis (SEM), indicated that the films FT3 and FT4 possessed the best physicochemical properties to protect Hass avocadoes against the soft rot produced by C. rosea. Avocadoes treated with the films FT3 and FT4 significantly (p < 0.01) conserved fruit firmness and nutritional composition (protein, fat, fiber, and reducing sugars) as well as the nutraceutical content (oleic, palmitoleic, linoleic, and palmitic acids) of infected avocados for 21 days. Our results validate the potential use of the films FT3 and FT4 to prevent the soft rot caused by C. rosea and to improve the shelf life of Hass avocadoes.

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There is increasing pressure to identify natural feed additives to mitigate methane emissions from livestock systems. Our objective was to investigate the effects of essential oils (EO) extracts star anise (Illicium verum), citronella (Cymbopogon winterianus), clove bud (Eugenia caryophyllus), staigeriana eucalyptus (Eucalyptus staigeriana), globulus eucalyptus (Eucalyptus globulus), ginger (Zingiber officinale), ho wood (Cinnamomum camphora), melaleuca (Melaleuca alternifolia), oregano (Origanum vulgare) and white thyme (Thymus vulgaris) on in vitro methane emissions from four rumen-cannulated Nellore cattle grazing a tropical grass pasture as inoculum donors. The semi-automated gas production technique was used to assess total gas production, dry matter degradability, partitioning factor, ammoniacal nitrogen, short-chain fatty acids and methane production. All essential oils were tested in four doses (0, 50, 250 and 500 mg/L) in a randomized block design, arranged with four blocks, 10 treatments, four doses and two replicates. Within our study, oregano and white Thyme EO reduced net methane production at 250 mg/L, without affecting substrate degradation. Essential oils from oregano and white thyme have the potential to modify ruminal fermentation and suppress rumen methanogenesis without negative effects on feed digestibility, indicating promise as alternatives to ionophores for methane reduction in beef cattle.

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Introducción: es conocida la actividad del aceite esencial de tomillo como promotor de crecimiento en pollos de engorde, pero su aplicación directa en producción se dificulta debido a su inestabilidad asociada a su alta volatilización. Objetivo: desarrollar un microencapsulado que incluya al aceite esencial de tomillo y se evalúe su desempeño en campo. Metodología: la técnica empleada para la microencapsula-ción fue la de secado por aspersión, utilizando como biopolímeros goma arábiga (GA), maltodextrina (M) o almidón de ñame succinatado (AÑS). Se establecieron las condiciones de emulsificación (paso previo a la microencapsulación), así como las condiciones para la obtención de las micropartículas, mediante la aplicación de un diseño estadístico experimental (DEE). Adicionalmente, se caracterizó la morfología, estabilidad, comportamiento de liberación y desempeño en campo de la formulación obtenida bajo las condiciones definidas. Resultados: se seleccionaron las matrices de los biopolímeros GA/M y GA/M/AÑS que conformaron el material de recubrimiento de las micropartículas. La eficiencia de encapsulación fue de 87,5 %, su tamaño de partícula de 74,5 µm, su índice de dispersión de 2,4 y tuvo un rendimiento de 48,5%. El ensayo de estabilidad demostró que la cubierta polimèrica ejerce cierta protección a la pérdida del aceite esencial. Los estudios de liberación evidenciaron la modulación de la liberación del activo. El estudio en campo demostró que el sistema microparticulado presenta un comportamiento estadísticamente similar al producto comercial que sirvió de comparador. Conclusión: este microencapsulado podría ser empleado como promotor de crecimiento en la producción de pollos de engorde.

SUMMARY Introduction: The biological activity of the thyme essential oil is known to work as growth promoter on broilers, but its direct applicability on production is difficult due to its instability associated to its volatilization. Aim: To develop a micro-encapsulated thyme essential oil and its performance in diets for broiler chickens. Methodology: The technique used for the microencapsulation was the spray drying process, using the Gum Arabic (GA), Maltodextrin (M) or Starch Yam succinate (SYS) as biopolymers. The emulsification conditions (previous step to the micro-encapsulation) and the conditions to obtain the microparticles were stablished, through the implementation of a statistical experimental design (SED) The formulation obtained under defined conditions is additionally characterized in terms of morphology, stability, release behavior and field performance. Results: The biopolymer matrixes GA/M and GA/M/SYS were selected for the covering material of the microparticles. The encapsulation efficacy was 87.5 %, its particle size was 74.5 [zm, the dispersity index 2.4 and a yield of 48,5%. The stability test proved that polymeric cover exerts some protection to the loss of the essential oil. The release studies demonstrated the release modulation of the active ingredient. The field study proved that the microparticulate system presents a statistical behavior like the commercial product used as comparator. Conclusion: This approach suggests that this microencapsulation method could be used as a growth promoter in the production of broiler chickens.

Introdução: a atividade do óleo essencial de tomilho como promotor de crescimento em frangos de corte é conhecida, mas sua aplicação direta na produção é difícil devido à sua instabilidade associada à sua alta volatilização. Objetivo: desenvolver um microencapsulado que inclua óleo essencial de tomilho e avaliar seu desempenho em campo. Metodologia: a técnica utilizada para microencapsulação foi a secagem por spray dryer, utilizando como biopolímeros goma arábica (GA), maltodextrina (M) ou amido succinato de inhame (ASI). As condições de emulsificação (etapa anterior à microencapsulação) foram estabelecidas, bem como as condições de obtenção das micropartículas, através da aplicação de um desenho estatístico experimental (DEE). Adicionalmente, foram caracterizados a morfologia, estabilidade, comportamento de liberação e desempenho em campo da formulação obtida nas condições definidas. Resultados: foram selecionadas as matrizes biopoliméricas GA/M e GA/M/AÑS que formaram o material de revestimento das micropartículas. A eficiência de encapsulamento foi de 87,5 %, seu tamanho de partícula foi de 74,5 [zm, seu índice de dispersão foi de 2,4 e teve um rendimento de 48,5%. O teste de estabilidade mostrou que a cobertura polimérica exerce alguma proteção contra a perda de óleo essencial. Os estudos de liberação evidenciaram a modulação da liberação do princípio ativo. O estudo de campo mostrou que o sistema microparticulado apresenta comportamento estatisticamente semelhante ao produto comercial que serviu de comparador. Conclusão: este microencapsulado pode ser utilizado como promotor de crescimento na produção de frangos de corte.

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Research in aquaculture shows that thymol and carvacrol are promising additives in fish diets. In this study, the effects of the thymol:carvacrol combination on health parameters and the zootechnical performance of tambaqui (Colossoma macropomum) were evaluated. The compounds were incorporated into five concentrations of feed. At intervals of 30 and 60 days, fish were sampled to evaluate haematological, biochemical, and immunological parameters, and after 60 days, zootechnical performance, parasitic load, and resistance to bacteriosis were evaluated. After 30 days, fish that received the highest concentrations of thymol:carvacrol showed a reduction in the number of thrombocytes and lymphocytes and an increase in eosinophils (p ≤ 0.05). After 60 days of feeding, haematological parameters were similar between all groups. Regarding the antiparasitic effect of the compounds, all groups had a high parasitic load (monogenean infestation). Regarding the prevention of bacteriosis, high mortality was detected in all groups after the experimental challenge with Aeromonas jandaei, with no greater protection for fish fed thymol:carvacrol. In conclusion, it was observed that haematological results corroborate with research on mammals, in which the anti-inflammatory/immunosuppressive effects of thymol and carvacrol are highlighted. However, the use of additives for aquaculture should be dis-cussed carefully, as the cost-benefit of supplementation is not a consensus.

Pesquisas em aquicultura mostram que timol e carvacrol são aditivos promissores na dieta de peixes. Neste estudo, foram avaliados os efeitos da combinação timol:carvacrol sobre parâmetros de saúde e o desempenho zootécnico de tambaqui (Colossoma macropomum). Os compostos foram incorporados em cinco concentrações na dieta. Em intervalos de 30 e 60 dias, peixes foram amostrados para avaliação hematológica, bioquímica e imunológica e, após 60 dias, para desempenho zootécnico, carga parasitária e resistência à bacteriose. Após 30 dias, peixes que receberam maiores concentrações de timol:carvacrol apresentaram redução de trombócitos e linfócitos e aumento dos eosinófilos (p ≤ 0,05). Após 60 dias de alimentação, os parâmetros hematológicos foram semelhantes entre todos os grupos. Com relação ao efeito antiparasitário dos compostos, todos os grupos apresentaram alta carga parasitária (infestação monogênica). Quanto à prevenção da bacteriose, foi detectada alta mortalidade em todos os grupos após desafio com Aeromonas jandaei, não havendo maior proteção para os peixes alimentados com timol:carvacrol. Em conclusão, observou-se que os resultados hematológicos corroboram pesquisas em mamíferos, que destacam a ação anti-inflamatória/imunossupressora do timol e do carvacrol. No entanto, o uso desses aditivos para a aquicultura merece ser discutido cautelosamente, pois o custo-benefício dessa suplementação para o produtor não é um consenso.

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Background: Periodontal disease is the infection and inflammation of the gums, bones, and tissues involved in teeth support, and it is one of the most common diseases affecting pet dogs. Essential oils have shown antimicrobial activity against bacteria causing periodontal disease; therefore, they are considered potential therapeutic agents. Objectives: The main objective was to formulate and evaluate the antimicrobial activity of a 0.2% chlorhexidine canine mouthwash with essential oils. Methods: Three microemulsion formulations were obtained by constructing a pseudo-ternary phase diagram using the phase titration method. Different surfactant agents were evaluated, and hydrogenated castor oil was selected as the emulsifier agent. The antimicrobial activity of oregano essential oil (Origanum vulgare), thyme essential oil (Thymus vulgaris), and the three formulations were evaluated against Staphylococcus aureus, Streptococcus mutans, Streptococcus salivarius, and Escherichia coli. Results: Pure thyme and oregano essential oils showed higher antimicrobial activity than a 0,2% chlorhexidine solution. The formulations with essential oils plus chlorhexidine and chlorhexidine alone showed antimicrobial activity. The formulation containing only essential oils did not show antimicrobial activity. Conclusions: A canine mouthwash was formulated with chlorhexidine and thyme, and oregano essential oil. Based on the evaluation of antimicrobial activity, two of the proposed formulations could be a therapeutic option to reduce the risk and prevent periodontal disease in canines

Antecedentes: La enfermedad periodontal es la infección e inflamación de las encías, huesos y tejidos que brindan soporte a los dientes, es una de las enfermedades más comunes que afectan a los perros de compañía. Los aceites esenciales han mostrado actividad antimicrobiana contra las bacterias que causan la enfermedad periodontal; por lo tanto, son considerados como potenciales agentes terapéuticos. Objetivos: El objetivo principal de este trabajo fue formular y evaluar la actividad antimicrobiana de un colutorio canino de clorhexidina al 0,2% con aceites esenciales. Métodos: Se obtuvo tres formulaciones en microemulsión mediante la construcción de un diagrama de fase pseudoternario por el método de titulación de fase. Se evaluaron diferentes tensioactivos y se seleccionó el aceite de ricino hidrogenado como agente emulsificante de la formulación. La actividad antimicrobiana del aceite esencial de orégano (Origanum vulgare), el aceite esencial de tomillo (Thymus vulgaris) y las tres formulaciones fue evaluada contra Staphylococcus aureus, Streptococcus mutans, Streptococcus salivarius y Escherichia coli. Resultados: Los aceites esenciales puros de tomillo y orégano mostraron una mayor actividad antimicrobiana que una solución de clorhexidina al 0,2%. Las formulaciones con aceites esenciales más clorhexidina y únicamente clorhexidina mostraron actividad antimicrobiana. Mientras que la formulación que contiene solo aceites esenciales no mostró actividad antimicrobiana. Conclusión: Se formuló un enjuague bucal canino con clorhexidina y aceite esencial de tomillo y orégano. Según la evaluación de la actividad antimicrobiana, dos de las formulaciones propuestas podrían ser una opción terapéutica para disminuir el riesgo y prevenir la enfermedad periodontal en caninos

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BACKGROUND: The use of the injectable products for soft tissue augmentation and treatment of skin aging is an uncomfortable, invasive and related to several complications, and chronic reactions, mainly after long-term application. Efforts to develop new topically active anti-aging products with fewer adverse effects are a huge challenge that should be faced. AIMS: We evaluated the anti-aging effects of a phytocosmetic preparation containing Thymus vulgaris associated with lecithin (ThymLec) on the facial wrinkles, expression lines, and face oval remodeling using a double-blind placebo-controlled clinical trial and in vitro cell culture assays. METHODS: A clinical trial was conducted to evaluate the effects of ThymLec 2% on the area, length, and depth of the perioral and crow's feet wrinkles, nasolabial and smile lines, as well as face oval remodeling in female volunteers using a sophisticated Bio3D Structured-light Scanner. In the in vitro studies using 3T3-L1 mouse embryonic fibroblasts, adiponectin was measured by immunoenzymatic assay, adipogenesis by the AdipoRed reagent method, and the PPAR-γ expression by RT-PCR analysis. RESULTS: Topical treatment with ThymLec 2% reduced facial wrinkles and expression lines promoting a face oval remodeling. In the in vitro studies, ThymLec upregulated the PPAR-γ expression increasing adiponectin production and stimulating the adipogenesis process. CONCLUSIONS: The phytocosmetic preparation containing Thymus vulgaris and lecithin is an innovative and safe topical anti-aging product promoting fat tissue augmentation by adipogenesis stimulation via the upregulation of PPAR-γ expression and adiponectin production.

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Pectobacterium carotovorum is a phytopathogenic bacteria that causes significant economic loses in food crops, such as bell pepper, which is of special significance in the value of production and trade in Mexico. Therefore, a solution for fruit conservation must be sought. Due to environmental concerns, it is necessary the use of environmentally-friendly active packaging. In this article, chitosan and chitosan-thyme essential oil nanocoatings were used for the preservation of green bell pepper. Different formulations based on chitosan nanoparticles (CSNPs) and chitosan-thyme essential oil nanoparticles (15, 30, and 45%) were prepared. For uncoated and coated bell peppers, the quality and physiological variables of inoculated and uninoculated fruit with P. carotovorum during 12-day storage period were assessed. According to the results, the weight loss of the fruit remained almost constant over the storage days for the different formulations. A decrease in fruit firmness and an increase in the respiration rate and ascorbic acid content until day 8 with a decrease at the end of the storage period were observed. Of all the evaluated nanocoatings, the fruit treated with the formulation containing 15% CSNPs showed the lowest colony-forming units and disease incidence. Also, the coated bell peppers with this formulation had lower CO2 production compared to the remaining treatments, and the weight loss and firmness were maintained. Therefore, the use of CSNP coatings could represent a good alternative for the protection of bell pepper against the pathogenic bacteria P. carotovorum. PRACTICAL APPLICATION: The results of the application of nanocoatings based on chitosan and chitosan-thyme essential oil as an antibacterial agent against P. carotovorum on green bell pepper during 12-day storage period suggest that nanoparticle-based coatings can be a natural option for the preservation of fruit quality during ripening.

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Reducing livestock negative environmental impacts get great interest in last years. So, present study was carried out to determine the effect of adding different levels of mixture of thyme and celery versus salinomycin on ruminal fermentation, gas production, dry, organic matter and fiber degradation. Four experimental treatments were used by in-vitro batch culture technique, as follow: 60% CFM, 40% clover hay (control), control diet + 2.5 gm thyme + 2.5 gm celery kg-1 DM (T1), control diet + 5 gm thyme + 5 gm celery kg-1 DM (T2), control diet + 10 gm thyme + 10 gm celery kg-1 DM (T3), control diet + 0.4 gm Salinomycin kg-1 DM (T4). Ruminal pH value was significantly increased (p 0.05) between control and other treatments except for T1 that recorded the lowest value (p < 0.05). It is concluded that mixture of thyme plus celery could be alternate for ionophores in the ruminant diets to enhance ruminal fermentation, reducing gas production without any negative effect on nutrients degradability.

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Reducing livestock negative environmental impacts get great interest in last years. So, present study was carried out to determine the effect of adding different levels of mixture of thyme and celery versus salinomycin on ruminal fermentation, gas production, dry, organic matter and fiber degradation. Four experimental treatments were used by in-vitro batch culture technique, as follow: 60% CFM, 40% clover hay (control), control diet + 2.5 gm thyme + 2.5 gm celery kg-1 DM (T1), control diet + 5 gm thyme + 5 gm celery kg-1 DM (T2), control diet + 10 gm thyme + 10 gm celery kg-1 DM (T3), control diet + 0.4 gm Salinomycin kg-1 DM (T4). Ruminal pH value was significantly increased (p < 0.05) with T4 compared with other treatments. While, the T4 recorded the lowest value (p < 0.05) for microbial protein, short chain fatty acids concentrations (SCFA), total gas production, dry matter and organic matter degradability (DMd and OMd) compared with other treatments. Fiber fraction degradability (NDFd and ADFd) appeared no significant variance (p > 0.05) between control and other treatments except for T1 that recorded the lowest value (p < 0.05). It is concluded that mixture of thyme plus celery could be alternate for ionophores in the ruminant diets to enhance ruminal fermentation, reducing gas production without any negative effect on nutrients degradability.(AU)

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Edible coatings are safe, legal, and sensory acceptable for food applications and they can be incorporated as natural additives due to their antimicrobial activity, thickening capacity, nutrient content, and bioactive agents for protecting seafood from physical, chemical, and microbiological damage that affects its shelf-life. This study aimed to evaluate the effect of the guar gum bioactive coating with thyme oil on the quality of tilapia fish fillets for 15 days of storage at 4 °C, as a means to extend shelf-life. pH, moisture, ash, fat, color, thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), microbiological, and sensory examinations were investigated, and the results were analyzed by analysis of variance. The treatments were control (uncoated, UC), GGC (coated with guar gum, GGC), and guar gum combined with thyme oil (GGCTH). Tilapia fillets were stored at 4 °C, the safe temperature for refrigerated storage for 15 days. GGCTH had a slower increase of pH after 15 days of storage in comparison with GGC and UC (p < 0.05). GGC and GGCTH resulted in lower and lowest lightness (L*; p < 0.05) values, lower and lowest redness (a*; p < 0.01) values, and greater and greatest yellowness (b*; p < 0.05) values compared to UC, respectively. UC reduced shear force at 5 (0.37 kgf), 10 (0.32 kgf), and 15 (0.30 kgf) days post-storage in comparison with GGC (0.43, 0.43, and 0.43 kgf) and GGCTH (0.43, 0.44, and 0.44 kgf), respectively. There was less (p < 0.05) deterioration, as well as differences in textural and sensorial variables between uncoated and coated fish fillets. The microbiological analyses demonstrated that there was greater microbial growth in the uncoated fillets than in the coated ones. It was concluded that this bioactive coating with thyme oil retards microbial colonization of fish and reduces degradability of quality variables, therefore, it is a reliable and effective alternative to extend the shelf-life of tilapia fillets.

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Food packaging faces the negative impact of synthetic materials on the environment, and edible coatings offer one alternative from filmogenic suspensions (FS). In this work, an active edible FS based on chitosan (C) and quinoa protein (QP) cross-linked with transglutaminase was produced. Thyme (T) and rosemary (R) essential oils (EOs) were incorporated as antimicrobial agents. Particle size, Z potential, and rheological parameters were evaluated. The antimicrobial activity against Micrococcus luteus (NCIB 8166) and Salmonella sp. (Lignieres 1900) was monitored using atomic force microscopy and image analysis. Results indicate that EOs incorporation into C:QP suspensions did not affect the Z potential, ranging from -46.69 ± 3.19 mV to -46.21 ± 3.83 mV. However, the polydispersity index increased from 0.51 ± 0.07 to 0.80 ± 0.04 in suspensions with EO. The minimum inhibitory concentration of active suspensions against Salmonella sp. was 0.5% (v/v) for thyme and 1% (v/v) for rosemary. Entropy and fractal dimension of the images were used to confirm the antimicrobial effect of EOs, which modified the surface roughness.

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The food industry and the frozen fish sector in particular have benefitted greatly from advancements in food processing technologies. This study investigated the effect of adding natural antioxidants such as rosemary and thyme oil to frozen fillets of Nile tilapia (Oreochromis niloticus) in order to preserve their quality for consumers. Fillets were treated with rosemary and thyme at two concentrations (1% and 1.5%) and then were stored at 4°C. Samples were analyzed over 4 days for bacteriological (aerobic plate count, psychotropic count, and coliform count), chemical (determination of pH, thiobarbituric acid reactive substances-TBARS, and total volatile base nitrogen-TVB-N), and sensory quality examination (color, texture, and odor). Significant differences (P<0.05) were observed among different groups in terms of aerobic plate count, psychotropic count, and coliform count during the storage. Moreover, pH, TVB-N, and TBARS mean values in the treated groups were lower than those in the untreated group. The best sensory quality was obtained at the highest concentrations (1.5%) of thyme and rosemary oil.(AU)

A indústria de alimentos e o setor de peixes congelados, em particular, se beneficiaram dos avanços nas tecnologias de processamento de alimentos. Este estudo investigou o efeito da adição de antioxidantes naturais, como óleo de alecrim e tomilho, a filetes congelados de tilápia do Nilo (Oreochromis niloticus), a fim de preservar sua qualidade para os consumidores. Os filés foram tratados com alecrim e tomilho em duas concentrações (1% e 1,5%) e, em seguida, foram armazenados a 4°C. As amostras foram analisadas durante 4 dias para análises bacteriológicas (contagem de placas aeróbicas, psicotrópicas e coliformes), químicas (determinação do pH, substâncias reativas ao ácido tiobarbitúrico-TBARS e nitrogênio base volátil total-TVB-N) e exame da qualidade sensorial (cor, textura e odor). Diferenças significativas (P<0,05) foram observadas entre os diferentes grupos na contagem aeróbia de placas, contagem psicotrópica e contagem de coliformes durante o armazenamento. Além disso, os valores médios de pH, TVB-N e TBARS nos grupos tratados foram inferiores aos do grupo não tratado. A melhor qualidade sensorial foi obtida nas maiores concentrações (1,5%) de tomilho e óleo de alecrim.(AU)

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Potato common scab is a worldwide disease mainly caused by Streptomyces scabiei. It seriously affects potato crops by decreasing tuber quality. Essential oils (EO) are natural products with recognised antimicrobial properties. In this research, the antibacterial activities of thyme, oregano, suico and mint EO against S. scabiei were analysed. Infected tubers and soil samples were used for bacterial isolation; the obtained isolates were genetically identified. The chemical composition of the EO was determined by GC-MS. The broth microdilution method was used to analyse antibacterial properties of EO. Thirty-one bacterial isolates were obtained. The isolate chosen for antibacterial assays was morpho-physiologically and genetically identified as S. scabiei. Thyme EO was mainly composed of thymol and o-cymene; suico EO of dihydrotagetone, trans-tagetone and verbenone; oregano EO of trans-sabinene hydrate, thymol and É£-terpinene; and mint EO of menthone and menthol. All the EO tested were effective against S. scabiei, but thyme and suico EO were the most successful, with a minimum inhibitory concentration of 0.068 g·l-1 and 0.147 g·l-1 , respectively, and a minimum bactericidal concentration of 0.137 g·l-1 and 0.147 g·l-1 , respectively. Scanning electron microscopy showed similar damage caused by both thyme and suico EO to the bacterial envelope. Total phenolic content of EO was not related to their antibacterial activity. Thyme and suico EO are effective antibacterial agents against S. scabiei, impeding bacterial viability and disturbing the bacterial cell envelope. These EO are promising tools for control of potato common scab.

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Pectobacterium carotovorum was incubated in formulations of chitosan nanoparticles or thyme essential oil-loaded chitosan nanoparticles for a maximum period of 48 h time. The cellular changes and viability were evaluated by transmission electron microscopy (TEM), and two colorimetric assays 3-(4,5 dimethylthiazol-2-yl)-2,5diphenyl tetrazolium bromide (MTT) and alamar blue (AMB), respectively. The incubation time and the addition of the secondary metabolite to the formulation were key factors to the cell damage and cell inhibitory effects on P. carotovorum, TEM observations overall demonstrated on the treated bacterium, cell surface alterations such as deforming and disappearance of the cell wall and the plasmatic membrane, with agglomeration of nanoparticles outside and inside of the cells, loss of cell content and lysis. Cell viability was reduced about 80% (MTT) and 100% (AMB) in the applied treatment of chitosan-loaded thyme essential oil nanoparticles after 48 h incubation, in addition, the total cell inhibition was shown from 6 h incubation onwards with the AMB assay. The TEM micrographs and the cell viability assays provided enough evidence of the antimicrobial activity of the nanostructured formulations compared with the control where no damage was observed.

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