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1.
Biotechnol Appl Biochem ; 71(4): 753-765, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38436528

RESUMO

This study aimed to assess the technical feasibility of incorporating selenized Lactobacillus spp. microencapsulated via spray drying into cattle feed. Gum Arabic and maltodextrin were used as encapsulating agents. The encapsulation process was carried out with a drying air flow rate of 1.75 m3/min, inlet air temperature of 90°C, and outlet air temperature of 75°C. The viability of the encapsulated microorganisms and the technological characteristics of the obtained microparticles were evaluated. Microorganisms were incorporated into beef cattle feed to supplement their diet with up to 0.3 mg of Se per kilogram of feed. The encapsulated particles, consisting of a 50/50 ratio of gum Arabic/maltodextrin at a 1:20 proportion of selenized biomass to encapsulant mixture, exhibited superior technical viability for application in beef cattle feed. Supplemented feeds displayed suitable moisture, water activity, and hygroscopicity values, ensuring the preservation of viable microorganisms for up to 5 months of storage, with an approximate count of 4.5 log CFU/g. Therefore, supplementing beef cattle feed with selenized and microencapsulated lactic acid bacteria represents a viable technological alternative, contributing to increased animal protein productivity through proper nutrition.


Assuntos
Ração Animal , Suplementos Nutricionais , Secagem por Atomização , Animais , Bovinos , Ração Animal/análise , Selênio/química , Polissacarídeos/química , Lactobacillus/metabolismo , Composição de Medicamentos , Goma Arábica/química
2.
Nat Prod Res ; 38(10): 1647-1651, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37203185

RESUMO

Baccharis vulneraria Baker is used popularly for the treatment of skin infections. So, this study aimed investigate the antimicrobial activity and chemical characterization of the essential oil (EO) against microorganisms that cause cutaneous infections. The EO was analyzed by GC-MS. The antimicrobial test was performed using the serial microdilution method, and the antimicrobial activity was determined by the minimum inhibitory concentration against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Trichophyton interdigitale, Trichophyton rubrum, Fusarium solani and Fusarium oxysporum within the 32-0.0625 mg/mL concentration range. Were identified 31 EO compounds. Its major compounds are bicyclogermacrene, trans-cadin-1,4-diene, ß-caryophyllene, and germacrene A. EO showed antifungal action against T. rubrum and T. interdigitale (2 and 4 mg/mL MIC, respectively). The growth of C. albicans, at 4 mg/mL, decreased by 50% compared to control. The oil had no significant potential for other microorganisms at the selected concentrations.


Assuntos
Anti-Infecciosos , Baccharis , Óleos Voláteis , Óleos Voláteis/química , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Candida albicans , Testes de Sensibilidade Microbiana
3.
Artigo em Inglês | MEDLINE | ID: mdl-37950796

RESUMO

In this study, horseradish peroxidase was extracted, purified, and immobilized on a calcium alginate-starch hybrid support by covalent bonding and entrapment. The immobilized HRP was used for the biodegradation of phenol red dye. A 3.74-fold purification was observed after precipitation with ammonium sulfate and dialysis. An immobilization yield of 88.33%, efficiency of 56.89%, and activity recovery of 50.26% were found. The optimum pH and temperature values for immobilized and free HRP were 5.0 and 50 °C and 6.5 and 60 °C, respectively. The immobilized HRP showed better thermal stability than its free form, resulting in a considerable increase in half-life time (t1/2) and deactivation energy (Ed). The immobilized HRP maintained 93.71% of its initial activity after 45 days of storage at 4 °C. Regarding the biodegradation of phenol red, immobilized HRP resulted in 63.57% degradation after 90 min. After 10 cycles of reuse, the immobilized HRP was able to maintain 43.06% of its initial biodegradative capacity and 42.36% of its enzymatic activity. At the end of 15 application cycles, a biodegradation rate of 8.34% was observed. In conclusion, the results demonstrate that the immobilized HRP is a promising option for use as an industrial biocatalyst in various biotechnological applications.

4.
Food Chem ; 429: 136974, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37499504

RESUMO

The intricate balance between the beneficial and harmful effects of selenium (Se) intake means that its quantification in food needs to be done correctly. Therefore, in this review, we systematized 105 articles to identify the most studied methodologies, analytical techniques, and food matrices. Among the analytical techniques employed, inductively coupled plasma mass spectrometry (ICP-MS) (n = 29) emerged as the most commonly used method. The most prevalent hydrolysis methodology to digest Se in food matrices involved the use of nitric acid combined with ultrasound, which improved both the yield and digestion time. Optimal recovery values were achieved when total Se quantification accounted for the sum of Se(IV) and Se(VI) (94.4-99.4%) and for SeCys (88-96.5%). These findings are relevant for advancing methodological approaches, and their results emphasize the importance of developing alternative, faster, and lower-cost protocols for Se quantification in foods and beverages.


Assuntos
Análise de Alimentos , Selênio/química , Bebidas/análise , Limite de Detecção
5.
Water Sci Technol ; 84(2): 374-383, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34312344

RESUMO

Cephalexin (CEX) is an antibiotic commonly used to treat bacterial infections in humans and animals. However, it is also a micropollutant. Thus, this study evaluated the degradation of CEX using ultraviolet irradiation (UV-C) and analyzed the by-products as well as their residual antimicrobial activity. A reactor with a mercury vapor lamp was used for the degradation. Irradiated CEX solutions were collected over a period of 4 hours and analyzed using high-performance liquid chromatography coupled with mass spectrometry. For the residual antimicrobial activity the susceptibility test was performed using Staphylococcus aureus and Escherichia coli microorganisms by broth microdilution. It was found that CEX, after treatment, generated a metabolite with a mass of 150 m/z in 15 min. A four- and eightfold increase in the minimum inhibitory concentration of the drug against S. aureus and E. coli could be observed, respectively, after 20 min. Therefore, this treatment proved to be effective in the degradation of CEX, being able to degrade 81% of the initial molecule of the drug in 20 min. Furthermore, the antimicrobial activity of the CEX solution decreased as the irradiation time increased, indicating loss of antimicrobial function of the initial CEX molecule and the resulting by-products.


Assuntos
Cefalexina , Staphylococcus aureus , Animais , Antibacterianos/farmacologia , Escherichia coli , Humanos , Testes de Sensibilidade Microbiana
6.
Ci. Rural ; 50(8): e20190932, June 19, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-746123

RESUMO

Stimulation of seed germination may be due to acceleration of germination as well as due to seedling growth-promotion during early development. Plant hydrolysate can be applied as a stimulant. Thus, we aimed to verify the influence of the hydrolysates, obtained by alkaline or acid treatment, from tobacco (Nicotiana tabacum L.) crop residues (root and stem) on the seed germination process. Seed germination was studied with Oryza sativa (rice) and Zea mays (corn). Sixteen germination experiments of 50 seeds each were undertaken, with 4 replicates, soaked with hydrolysates diluted at 20 and 80%, in 2 and 3 mL of hydration volumes for 48 h. Germinated seeds were counted, at which point radicular protrusions were observed. Rootlets and aerial parts were collected, dried and weighed. The hydrolysates presented seedling nutrition potential to the corn, with ~50% more mass compared to the results with water at the same conditions, and the germination acceleration was not significant. For the tested rice seeds, the results were reversed, and the germination acceleration was significant with rates up to 94% after 48 h of incubation. Better results of germination were obtained with hydrolysate from acid treatment, and root or stem tobacco can be used for this purpose.(AU)


A estimulação da germinação das sementes pode ser devida à aceleração da germinação, bem como à melhoria do crescimento das mudas durante o desenvolvimento inicial. O hidrolisado de plantas pode ser aplicado como estimulante. Assim, objetivou-se verificar a influência dos hidrolisados, obtidos por tratamento alcalino ou ácido, dos resíduos da cultura do tabaco (Nicotiana tabacum L.) (raiz e caule) no processo de germinação das sementes. A germinação das sementes foi estudada com Oryza sativa (arroz) e Zea mays (milho). Foram realizados dezesseis experimentos de germinação de 50 sementes cada, com 4 repetições, hidratadas em hidrolisados diluídos a 20 e 80%, em 2 e 3 mL de volumes de hidratação por 48 h. As sementes germinadas foram contadas, momento em que foram observadas protrusões radiculares. Radículas e partes aéreas foram coletadas, secas e pesadas. Os hidrolisados apresentaram potencial nutricional de plântulas para o milho, com ~ 50% a mais de massa quando comparados aos resultados com água nas mesmas condições, e a aceleração da germinação não foi significativa. Para as sementes de arroz testadas, os resultados foram contrários e a aceleração da germinação foi significativa com taxas de até 94% após 48 h de incubação. Melhores resultados de germinação foram obtidos com hidrolisado a partir do tratamento ácido, e a raiz ou caule de tabaco pode ser utilizado para esse fim.(AU)


Assuntos
Hidrólise , Caules de Planta , Raízes de Plantas , Nicotiana , Germinação , Oryza , Zea mays , Sementes/efeitos dos fármacos
7.
Ciênc. rural (Online) ; 50(8): e20190932, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1133298

RESUMO

ABSTRACT: Stimulation of seed germination may be due to acceleration of germination as well as due to seedling growth-promotion during early development. Plant hydrolysate can be applied as a stimulant. Thus, we aimed to verify the influence of the hydrolysates, obtained by alkaline or acid treatment, from tobacco (Nicotiana tabacum L.) crop residues (root and stem) on the seed germination process. Seed germination was studied with Oryza sativa (rice) and Zea mays (corn). Sixteen germination experiments of 50 seeds each were undertaken, with 4 replicates, soaked with hydrolysates diluted at 20 and 80%, in 2 and 3 mL of hydration volumes for 48 h. Germinated seeds were counted, at which point radicular protrusions were observed. Rootlets and aerial parts were collected, dried and weighed. The hydrolysates presented seedling nutrition potential to the corn, with ~50% more mass compared to the results with water at the same conditions, and the germination acceleration was not significant. For the tested rice seeds, the results were reversed, and the germination acceleration was significant with rates up to 94% after 48 h of incubation. Better results of germination were obtained with hydrolysate from acid treatment, and root or stem tobacco can be used for this purpose.


RESUMO: A estimulação da germinação das sementes pode ser devida à aceleração da germinação, bem como à melhoria do crescimento das mudas durante o desenvolvimento inicial. O hidrolisado de plantas pode ser aplicado como estimulante. Assim, objetivou-se verificar a influência dos hidrolisados, obtidos por tratamento alcalino ou ácido, dos resíduos da cultura do tabaco (Nicotiana tabacum L.) (raiz e caule) no processo de germinação das sementes. A germinação das sementes foi estudada com Oryza sativa (arroz) e Zea mays (milho). Foram realizados dezesseis experimentos de germinação de 50 sementes cada, com 4 repetições, hidratadas em hidrolisados diluídos a 20 e 80%, em 2 e 3 mL de volumes de hidratação por 48 h. As sementes germinadas foram contadas, momento em que foram observadas protrusões radiculares. Radículas e partes aéreas foram coletadas, secas e pesadas. Os hidrolisados apresentaram potencial nutricional de plântulas para o milho, com ~ 50% a mais de massa quando comparados aos resultados com água nas mesmas condições, e a aceleração da germinação não foi significativa. Para as sementes de arroz testadas, os resultados foram contrários e a aceleração da germinação foi significativa com taxas de até 94% após 48 h de incubação. Melhores resultados de germinação foram obtidos com hidrolisado a partir do tratamento ácido, e a raiz ou caule de tabaco pode ser utilizado para esse fim.

8.
Braz. J. Pharm. Sci. (Online) ; 55: e17584, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1039064

RESUMO

In South American folk medicine members of the genus Myrciaria are used for the treatment of malaria, diarrhoea, asthma, inflammation and post-partum uterine cleansing. The aim of this work was to evaluate its antileishmanial properties (in vitro) of essential oil derived from leaves of Myrciaria plinioides D. Legrand, a plant species that is native in South of Brazil. The essential oil was obtained by hydro-distillation using fresh leaves of M. plinioides. The chemical composition of this essential oil (MPEO, M. plinioides essential oil) was determined by gas chromatography coupled to mass spectrometry (GC-MS). MPEO was assayed in vitro for antileishmanial properties against promastigotes of Leishmania amazonensis and Leishmania infantum, and for cytotoxicity against murine peritoneal macrophages. The MPEO comprised 66 components and was rich in oxygenated sesquiterpenes (82.66%) containing spathulenol (21.12%) as its major constituent. The MPEO was effective against L. amazonensis with IC50 value of 14.16 ± 7.40 µg/mL, while against L. infantum the IC50 value was higher with 101.50 ± 5.78 µg/mL. The MPEO showed significant activity against L. amazonensis, and presented a selectivity index (SI) of 6.60. The results suggest that the essential oil from leaves of M. plinioides is a promising source for new antileishmanial agents against L. amazonensis.


Assuntos
Técnicas In Vitro/instrumentação , Brasil/etnologia , Óleos Voláteis/análise , Myrtaceae/anatomia & histologia , Leishmania infantum , Folhas de Planta/classificação , Leishmania
9.
J Dairy Sci ; 101(12): 10626-10635, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30316597

RESUMO

Selenium is an essential micronutrient for living beings, as it helps to maintain the normal physiological functions of the organism. The numerous discoveries involving the importance of this element to the health of human beings have fostered interest in research to develop enriched and functional foods. The present study evaluated the potential for bacterial strains of Enterococcus faecalis (CH121 and CH124), Lactobacillus parabuchneri (ML4), Lactobacillus paracasei (ML13, ML33, CH135, and CH139), and Lactobacillus plantarum (CH131) to bioaccumulate Se in their biomass by adding different concentrations of sodium selenite (30 to 200 mg/L) to the culture medium. Quantification of Se with UV and visible molecular absorption spectroscopy showed that the investigated bacteria were able to bioaccumulate this micromineral into their biomass. Two of the L. paracasei strains (ML13 and CH135) bioaccumulated the highest Se concentrations (38.1 ± 1.7 mg/g and 40.7 ± 1.1 mg/g, respectively) after culture in the presence of 150 mg/L of Se. This bioaccumulation potential has applications in the development of dairy products and may be an alternative Se source in the diets of humans and other animals.


Assuntos
Enterococcus faecalis/metabolismo , Lactobacillus/metabolismo , Selênio/metabolismo , Animais , Bovinos , Meios de Cultura/análise , Meios de Cultura/metabolismo , Laticínios/microbiologia , Enterococcus faecalis/genética , Enterococcus faecalis/crescimento & desenvolvimento , Humanos , Ácido Láctico/metabolismo , Lactobacillus/crescimento & desenvolvimento , Selenito de Sódio/análise , Selenito de Sódio/metabolismo
10.
ACS Omega ; 3(6): 6476-6482, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30023949

RESUMO

Three tobacco types (Burley, Flue Cured, and Oriental) and eight cigarette brands were unequivocally identified using an electronic nose formed by only three sensors based on a single novel conducting polymer (PF-BTB) doped with different porphyrins (H2TPP, H2TPFP, and H2BTBOP). The synthesis and characterization of the polymer are also discussed. Small changes in the porphyrin structure caused significant changes in the electrical conductance response patterns of the sensors upon exposure to complex chemical matrixes, representing a novel approach for tuning the selectivity of chemiresistive sensors for e-nose application. This e-nose is fast, cheap, reliable, can be easily operated, and could be a valuable tool for border agents fighting cigarette smuggling around the world, helping them prevent losses of millions in tax revenues and sales.

11.
J Environ Sci Health B ; 53(4): 229-236, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29319411

RESUMO

The aim of this study was to develop a cantilever nanobiosensor for atrazine detection in liquid medium by immobilising the biological recognition element (tyrosinase vegetal extract) on its surface with self-assembled monolayers using gold, 16-mercaptohexadecanoic acid, 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/n-hydroxysuccinimide. Cantilever nanobiosensors presented a surface compression tension increase when atrazine concentrations were increased, with a limit of detection and limit of quantification of 7.754 ppb (parts per billion) and 22.792 ppb, respectively. From the voltage results obtained, the evaluation of atrazine contamination in river and drinking water were very close to those of the reference sample and ultrapure water, demonstrating the ability of the cantilever nanobiosensor to distinguish different water samples and different concentrations of atrazine. Cantilever nanosensor surface functionalization was characterised by combining polarisation modulation infrared reflection-absorption spectroscopy and atomic force microscopy and indicating film thickness in nanometric scale (80.2 ± 0.4 nm). Thus, the cantilever nanobiosensor developed for this study using low cost tyrosinase vegetal extract was adequate for atrazine detection, a potential tool in the environmental field.


Assuntos
Atrazina/análise , Técnicas Biossensoriais , Monofenol Mono-Oxigenase/metabolismo , Nanotecnologia , Água Potável/química , Contaminação de Alimentos/análise , Ouro/química , Herbicidas/análise , Imidas/química , Limite de Detecção , Musa/química , Musa/enzimologia , Ácidos Palmíticos/química , Extratos Vegetais/química , Propilaminas/química , Rios/química , Propriedades de Superfície
12.
An. acad. bras. ciênc ; 89(3): 1381-1389, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886739

RESUMO

ABSTRACT A new modified electrode for indirect sensing of OH· and radical scavengers was described. The electrochemical polymerization of methylene blue in aqueous solutions and the properties of the resulting films on a glassy carbon electrode were carried out using cyclic voltammetry. A surface coverage of 1.11 × 109mol cm2 was obtained, revealing a complete surface coverage of the polymeric film on the electrode surface. OH· was able to destroy the poly(methylene blue) film by exposure to a Fenton solution. The loss of the electrochemical signal of the residual polymeric film attached to the electrode surface was related to the extent of its dissolution. The applicability of the sensor was demonstrated by evaluating the OH radical scavenging effect on different concentrations of ascorbic acid. The obtained radical scavenging capacity were 31.4%, 55.7%, 98.9% and 65.7% for the ascorbic acid concentrations of 5, 10, 30 and 50 mM, respectively.


Assuntos
Sequestradores de Radicais Livres/química , Azul de Metileno/química , Relação Estrutura-Atividade , Eletrodos , Técnicas Eletroquímicas
13.
An Acad Bras Cienc ; 89(3): 1381-1389, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813104

RESUMO

A new modified electrode for indirect sensing of OH· and radical scavengers was described. The electrochemical polymerization of methylene blue in aqueous solutions and the properties of the resulting films on a glassy carbon electrode were carried out using cyclic voltammetry. A surface coverage of 1.11 × 109mol cm2 was obtained, revealing a complete surface coverage of the polymeric film on the electrode surface. OH· was able to destroy the poly(methylene blue) film by exposure to a Fenton solution. The loss of the electrochemical signal of the residual polymeric film attached to the electrode surface was related to the extent of its dissolution. The applicability of the sensor was demonstrated by evaluating the OH radical scavenging effect on different concentrations of ascorbic acid. The obtained radical scavenging capacity were 31.4%, 55.7%, 98.9% and 65.7% for the ascorbic acid concentrations of 5, 10, 30 and 50 mM, respectively.


Assuntos
Sequestradores de Radicais Livres/química , Azul de Metileno/química , Técnicas Eletroquímicas , Eletrodos , Relação Estrutura-Atividade
14.
Braz. j. microbiol ; Braz. j. microbiol;47(2): 424-430, Apr.-June 2016. tab
Artigo em Inglês | LILACS | ID: lil-780849

RESUMO

Abstract Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC–MS (gas chromatography–mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25 mg mL-1 for thyme, 5.0 mg mL-1 for basil and marjoram, and 10 mg mL-1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.


Assuntos
Óleos de Plantas/farmacologia , Óleos Voláteis/farmacologia , Clostridium perfringens/efeitos dos fármacos , Antibacterianos/farmacologia , Óleos de Plantas/análise , Brasil , Óleos Voláteis/análise , Testes de Sensibilidade Microbiana , Clostridium perfringens/crescimento & desenvolvimento , Ocimum basilicum/química , Rosmarinus/química , Origanum/química , Thymus (Planta)/química , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/análise
15.
Braz. J. Microbiol. ; 47(2): 424-430, Abr-Jun. 2016. tab
Artigo em Inglês | VETINDEX | ID: vti-23470

RESUMO

Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GCMS (gas chromatographymass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25 mg mL-1 for thyme, 5.0 mg mL-1 for basil and marjoram, and 10 mg mL-1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.(AU)


Assuntos
Óleos Voláteis/análise , Anti-Infecciosos , Clostridium perfringens/imunologia , Clostridium perfringens/isolamento & purificação
16.
Braz J Microbiol ; 47(2): 424-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26991289

RESUMO

Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC-MS (gas chromatography-mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25mgmL(-1) for thyme, 5.0mgmL(-1) for basil and marjoram, and 10mgmL(-1) for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.


Assuntos
Antibacterianos/farmacologia , Clostridium perfringens/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Antibacterianos/análise , Brasil , Clostridium perfringens/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Ocimum basilicum/química , Óleos Voláteis/análise , Origanum/química , Óleos de Plantas/análise , Rosmarinus/química , Thymus (Planta)/química
17.
Ciênc. rural ; Ciênc. rural (Online);45(12): 2164-2167, tab
Artigo em Português | LILACS | ID: lil-764529

RESUMO

RESUMO:O Rio Grande do Sul é o maior produtor nacional de arroz irrigado por alagamento do Brasil e algumas lavouras cultivam o arroz irrigado há mais de 100 anos. Nos cultivos, são utilizados insumos agrícolas, muitos dos quais apresentam metais pesados em sua composição. Essa preocupação leva em consideração principalmente os elementos não essenciais às plantas, como o Pb, Cr e Cd, e que oferecem risco à saúde humana. Esta pesquisa teve por objetivo quantificar os teores de Cd, de Cr e de Pb no arroz vendido nos estabelecimentos comerciais do RS. As extrações dos elementos das amostras foram feitas pelo método USEPA 3050B. Para as quantificações dos metais, foi utilizada a Espectrometria de Emissão Óptica por Plasma Acoplado Indutivamente (ICP-OES). Os elementos quantificados nas amostras de grãos vendidos em estabelecimentos comerciais apresentaram-se dentro dos limites permitidos pela legislação.


ABSTRACT:The state of Rio Grande do Sul (RS) is the largest producer of flood-irrigated rice in Brazil and some fields flooded rice are cultivated for more than 100 years. In rice production are being utilized various inputs, many of which have heavy metals in its composition. This preoccupation considers especially nonessential elements to plants such as Pb, Cr and Cd, which provide risks to human health. This study aimed to quantify the levels of Cd, Cr and Pb in rice grains sold in markets retailers in RS. The elements were extracted from the samples through the USEPA 3050B method and quantified by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The elements quantified in samples of grains rice sold in markets retailers were within the limits allowed by law.

18.
Ci. Rural ; 45(12): 2164-2167, Dec. 2015. tab
Artigo em Português | VETINDEX | ID: vti-760654

RESUMO

O Rio Grande do Sul é o maior produtor nacional de arroz irrigado por alagamento do Brasil e algumas lavouras cultivam o arroz irrigado há mais de 100 anos. Nos cultivos, são utilizados insumos agrícolas, muitos dos quais apresentam metais pesados em sua composição. Essa preocupação leva em consideração principalmente os elementos não essenciais às plantas, como o Pb, Cr e Cd, e que oferecem risco à saúde humana. Esta pesquisa teve por objetivo quantificar os teores de Cd, de Cr e de Pb no arroz vendido nos estabelecimentos comerciais do RS. As extrações dos elementos das amostras foram feitas pelo método USEPA 3050B. Para as quantificações dos metais, foi utilizada a Espectrometria de Emissão Óptica por Plasma Acoplado Indutivamente (ICP-OES). Os elementos quantificados nas amostras de grãos vendidos em estabelecimentos comerciais apresentaram-se dentro dos limites permitidos pela legislação.(AU)


The state of Rio Grande do Sul (RS) is the largest producer of flood-irrigated rice in Brazil and some fields flooded rice are cultivated for more than 100 years. In rice production are being utilized various inputs, many of which have heavy metals in its composition. This preoccupation considers especially nonessential elements to plants such as Pb, Cr and Cd, which provide risks to human health. This study aimed to quantify the levels of Cd, Cr and Pb in rice grains sold in markets retailers in RS. The elements were extracted from the samples through the USEPA 3050B method and quantified by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The elements quantified in samples of grains rice sold in markets retailers were within the limits allowed by law.(AU)


Assuntos
Cádmio , Cromo , Chumbo , Oryza/química , Irrigação Agrícola , Intoxicação por Metais Pesados
19.
Arch Environ Contam Toxicol ; 58(4): 1008-14, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19946682

RESUMO

Cadmium is a metal with no biological function in superior organisms and it is very toxic even at very low concentrations. Thus the objective of this study was to verify some toxicological parameters in silver catfish (Rhamdia quelen) exposed to cadmium. In this study, silver catfish was exposed to 0 (control), 0.236, and 0.414 mg L(-1) cadmium for 7 and 14 days, followed by the same periods of recovery. The effects of cadmium on acetylcholinesterase (AChE) activity and metal accumulation in brain and muscle were verified. Thiobarbituric acid-reactive substance (TBARS) formation was evaluated in brain. An increase in TBARS levels was verified after exposure and recovery periods and AChE activity in brain was reduced after 14 days of exposure. These parameters did not return to control values after the recovery period. In muscle AChE was altered during both exposure periods. Alterations in AChE activity may be a good indicator of cadmium contamination in R. quelen.


Assuntos
Acetilcolinesterase/metabolismo , Cádmio/toxicidade , Peixes-Gato , Peroxidação de Lipídeos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Encéfalo/metabolismo , Cádmio/farmacocinética , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/metabolismo , Dose Letal Mediana , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Poluentes Químicos da Água/farmacocinética
20.
Exp Parasitol ; 123(1): 35-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19463819

RESUMO

The aim of this study was to evaluate the concentrations of copper, iron and zinc in blood serum of cats experimentally infected with Trypanosoma evansi. Animals were divided into two groups: control and infected with T. evansi. The animals were infected with 10(8) trypomastigotes each and parasitemia was estimated daily for 56 days by microscopic examination of smears. Hematological and biochemical parameters were evaluated for monitoring of the disease. Serum metal levels were determined in blood samples collected at days 7, 28 and 56 of the experiment. Inductively coupled plasma optical emission spectrometry was used to measure the levels of copper, iron and zinc. Significant differences were observed among groups (P<0.05). Increased levels of copper and decreased iron and zinc levels were observed. A decrease in the number of red blood cells was also observed 7 days after inoculation. Biochemical parameters were not altered. Therefore, the infection by T. evansi might alter the serum metal levels, causing metabolic disturbances in cats.


Assuntos
Cobre/sangue , Ferro/sangue , Parasitemia/sangue , Tripanossomíase/sangue , Zinco/sangue , Animais , Gatos , Contagem de Eritrócitos , Feminino , Hematócrito
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