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1.
Arch Microbiol ; 202(10): 2779-2789, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32743668

RESUMO

Endophytes are considered one of the most important microbial resources for obtaining biomolecules of therapeutic use. Passiflora incarnata, widely employed by the pharmaceutical industry, shows therapeutic effects on anxiety, nervousness, constipation, dyspepsia and insomnia based on their antioxidant compounds. In this study, from 315 endophytic fungi isolated from P. incarnata leaves, 60 were selected to determinate presence of chemical constituents related with antioxidant activity, based on their production of soluble pigments. The promising fungi were evaluated specifically on their potential to produce phenolic compounds, flavonoids and for antioxidant activity. Five isolates significantly produced flavonoids and phenolic compounds in the ethyl acetate and n-Butanol extracts, also saponins and high antioxidant activity against the DPPH (2.2-diphenyl-1-picrylhydrazyl) free radical. A strain of Aspergillus nidulans var. dentatus (former Emericella dentata) was able to produce tannins as well; its butanolic extract was very similar than the BHT (butylated hydroxytoluene) (94.3% × 94.32%) and Rutin (95.8%) reference substances in the DPPH radical scavenging. Similarly, a Chaetomium strain exhibited 93.6% and 94.7% of antioxidant activity in their ethyl acetate and butanolic fractions, respectively. The chromatographic analysis of the ethyl acetate fraction from the Aspergillus strain revealed the production of orcinol (3.19%). Four-methoxymethylphenol (4.79%), sorbicillin (33.59%) and ergosterol (23.08%) was produced by Trichoderma longibrachiatum and isopropenyl-1,4-dimethyl-1,2,3,3a,4,5,6,7-octahydroazulene were found in two Fusarium oxysporum strains. The phytochemical screening showed that all analyzed fungi were able to produce a kind of secondary metabolite (phenols, flavonoids, tannins and/or saponins). The study shows a great underexplored potential for industrial application of P. incarnata endophytes.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Fungos/isolamento & purificação , Fungos/metabolismo , Passiflora/microbiologia , Fenóis/análise , Compostos de Bifenilo/análise , Endófitos/classificação , Endófitos/isolamento & purificação , Endófitos/metabolismo , Radicais Livres/análise , Fungos/classificação , Extratos Vegetais/química , Folhas de Planta/microbiologia , Taninos
2.
Acta Cir Bras ; 34(10): e201901002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826148

RESUMO

PURPOSE: To evaluate the effect of garlic on formation of postoperative adhesions in rats. METHODS: Twenty-four Sprague dawley rats were divided into three groups. In Group 1 (sham), laparotomy was performed and stitched up. In Group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and 2 cc of saline was intraperitoneally administered to each rat. In Group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Allium sativum derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum. RESULTS: In Group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. CONCLUSIONS: No positive outcomes indicating that Allium sativum reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, allium sativum increased the production of free oxygen radicals in the tissue.


Assuntos
Alho/química , Doenças Peritoneais/prevenção & controle , Animais , Fibrose , Radicais Livres/análise , Imuno-Histoquímica , Laparotomia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Estresse Oxidativo/efeitos dos fármacos , Doenças Peritoneais/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/prevenção & controle , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle
3.
Acta cir. bras ; Acta cir. bras;34(10): e201901002, Oct. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054669

RESUMO

Abstract Purpose: To evaluate the effect of garlic on formation of postoperative adhesions in rats. Methods: Twenty-four Sprague dawley rats were divided into three groups. In Group 1 (sham), laparotomy was performed and stitched up. In Group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and 2 cc of saline was intraperitoneally administered to each rat. In Group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Allium sativum derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum Results: In Group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. Conclusions: No positive outcomes indicating that Allium sativum reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, allium sativum increased the production of free oxygen radicals in the tissue.


Assuntos
Animais , Doenças Peritoneais/prevenção & controle , Alho/química , Doenças Peritoneais/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/prevenção & controle , Fibrose , Imuno-Histoquímica , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle , Reprodutibilidade dos Testes , Ratos Sprague-Dawley , Estresse Oxidativo/efeitos dos fármacos , Radicais Livres/análise , Laparotomia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia
4.
Food Res Int ; 123: 1-10, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31284956

RESUMO

Multivariate data analysis feasibility for the evaluation of Brazilian stingless bee honey (SBH) by pollen spectrum, bioactive compounds content, physicochemical, antioxidant and antimicrobial analysis was investigated. Levels of total and individual phenolics content were analyzed by HPLC-PDA. The antioxidant capacity was performed by 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), oxygen radical absorption capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. The total phenolic compounds from the thirty-two SBH was positively correlated with the antioxidant capacity. Bioactive compounds such as p-coumaric acid, quercetin, and hesperetin were identified in all the samples. Brazilian SBH shows more effective antibacterial activity against Gram-negative bacteria (E. coli and S. Typhimurium) compared to Gram-positive ones. Results also revealed that SBH could reach up to 45% higher antioxidant and biological activities than the traditional Apis mellifera honey. Chemometrics shows that chemical and biological properties of SBH have a strong relationship with the pollen botanical origin. Principal component analysis (PCA) grouped the honey into three categories with predominant pollen from Verbenaceae, Asteraceae and Sapindaceae families, confirming that SBH belonging to the same floral origin present similar characteristics.


Assuntos
Abelhas/classificação , Mel/análise , Pólen/química , Animais , Antibacterianos/análise , Antibacterianos/farmacologia , Antioxidantes/análise , Abelhas/metabolismo , Compostos de Bifenilo/análise , Brasil , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Radicais Livres/análise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/metabolismo , Indicadores e Reagentes/análise , Análise Multivariada , Fenóis/análise , Picratos/análise , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/metabolismo
5.
Nicotine Tob Res ; 21(9): 1274-1278, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-30346584

RESUMO

INTRODUCTION: Free radicals and carbonyls produced by electronic cigarettes (e-cigs) have the potential to inflict oxidative stress. Recently, Juul e-cigs have risen drastically in popularity; however, there is no data on nicotine and oxidant yields from this new e-cig design. METHODS: Aerosol generated from four different Juul flavors was analyzed for carbonyls, nicotine, and free radicals. The e-liquids were analyzed for propylene glycol (PG) and glycerol (GLY) concentrations. To determine the effects of e-liquid on oxidant production, Juul pods were refilled with nicotine-free 30:70 or 60:40 PG:GLY with or without citral. RESULTS: No significant differences were found in nicotine (164 ± 41 µg/puff), free radical (5.85 ± 1.20 pmol/puff), formaldehyde (0.20 ± 0.10 µg/puff), and acetone (0.20 ± 0.05 µg/puff) levels between flavors. The PG:GLY ratio in e-liquids was ~30:70 across all flavors with GLY being slightly higher in tobacco and mint flavors. In general, when Juul e-liquids were replaced with nicotine-free 60:40 PG:GLY, oxidant production increased up to 190% and, with addition of citral, increased even further. CONCLUSIONS: Juul devices produce free radicals and carbonyls, albeit, at levels substantially lower than those observed in other e-cig products, an effect only partially because of a low PG:GLY ratio. Nicotine delivery by these devices was as high as or higher than the levels previously reported from cigarettes. IMPLICATIONS: These findings suggest that oxidative stress and/or damage resulting from Juul use may be lower than that from cigarettes or other e-cig devices; however, the high nicotine levels are suggestive of a greater addiction potential.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Radicais Livres/análise , Nicotina/análise , Estresse Oxidativo/fisiologia , Aromatizantes/administração & dosagem , Aromatizantes/análise , Radicais Livres/administração & dosagem , Humanos , Nicotina/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Propilenoglicol/administração & dosagem , Propilenoglicol/análise
6.
An Acad Bras Cienc ; 90(3): 3115-3128, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30304239

RESUMO

This study was aimed to analyze the effects of spray-dried porcine plasma (SDPP) on the health of post weaning piglets challenged with diets contaminated with aflatoxins and fumonisins. Fifty-six male piglets (7.15 ± 0.61 kg) were allocated in four groups: CTL group received a regular diet; SDPP group received a regular diet and 6% SDPP; MYC group received a diet containing 300 µg/kg aflatoxins and 8,000 µg/kg fumonisins; group MYC+SDPP received 300 µg/kg aflatoxins, 8,000 µg/kg fumonisins and 6% SDPP. The animals that received the experimental diet containing mycotoxins (MYC group) had lower weight gain at the end of the experiment compared to the other treatments. Animals receiving SDPP showed decreased urea levels throughout the experiment (P<0.05). Animals from MYC group presented an increased on reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels and decreased catalase activity (P<0.05). In contrast, SDPP prevented the increase of ROS and TBARS and stimulated superoxide dismutase activity (P<0.05). In conclusion, diet contaminated with mycotoxins (group MYC) caused subclinical intoxication in the piglets, as observed by the increase on free radical's production and lipid peroxidation. Conversely, SDPP presented a protective effect, minimizing the effects of oxidative stress caused by aflatoxins and fumonisins ingestion.


Assuntos
Aflatoxinas/toxicidade , Ração Animal , Proteínas Sanguíneas/farmacologia , Suplementos Nutricionais/análise , Fumonisinas/toxicidade , Plasma , Suínos/crescimento & desenvolvimento , Animais , Modelos Animais de Doenças , Contaminação de Alimentos , Radicais Livres/análise , Peroxidação de Lipídeos , Fígado/metabolismo , Masculino , Aumento de Peso
7.
J Sci Food Agric ; 98(13): 5019-5026, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29603247

RESUMO

BACKGROUND: Grape seeds are a relatively abundant source of oil and bioactive compounds. To use this byproduct, the current work aimed to optimize the ultrasound-assisted extraction (UAE) of grape-seed oil to obtain greater process yield and minimize free radical formation in the oil. RESULTS: The optimal condition was 15 °C with an ultrasonic wave amplitude of 42 µm, leading to a process yield of 82.9% and content of free radicals of 14.7 × 1017 kg-1 and 3.4 × 1018 kg-1 for samples stored for 7 and 30 days, respectively. No significant differences in fatty acid composition and acidity and iodine values were observed between samples. The oil obtained by ultrasound had greater phenolic compound content and antioxidant activity by ferric reduction than the control sample (without ultrasound application). However, higher content of free radicals and peroxide value was observed. CONCLUSION: Sonication improved extraction yield when compared to the process without ultrasound application. Moreover, UAE favored the extraction of phenolic compounds. As it enhanced process yield with the minimum formation of free radicals, UAE is a promising oil-extraction technology. © 2018 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Radicais Livres/análise , Extratos Vegetais/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Ultrassom/métodos , Vitis/química , Ácidos Graxos/análise , Extratos Vegetais/análise , Óleos de Plantas/análise , Sementes/química
8.
Acta Cir Bras ; 33(2): 134-143, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29513812

RESUMO

PURPOSE: To investigate the effects of pycnogenol on peritoneal adhesions and additionally to investigate the immunohistochemical effects of free oxygen radicals and reactive lymph nodes detected in the adhesive tissue that was sampled surrounding the cecum on intra-abdominal adhesions. METHODS: Twenty-seven Wistar Albino rats were divided into three groups. In group 1 (sham), laparotomy was performed and stitched up. In group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered 2 cc of saline. In group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Pycnogenol derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum, and the rats were sacrificed. RESULTS: In group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. CONCLUSIONS: No positive outcomes indicating that pycnogenol reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Moreover, a significant increase in lymph node size was detected secondary to inflammation. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, pycnogenol increased the production of free oxygen radicals in the tissue.


Assuntos
Flavonoides/uso terapêutico , Linfonodos/efeitos dos fármacos , Doenças Peritoneais/prevenção & controle , Peritônio/cirurgia , Aderências Teciduais/prevenção & controle , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Flavonoides/efeitos adversos , Radicais Livres/análise , Imuno-Histoquímica , Inflamação/induzido quimicamente , Inflamação/patologia , Laparotomia , Linfonodos/patologia , Estresse Oxidativo/efeitos dos fármacos , Doenças Peritoneais/etiologia , Peritônio/patologia , Extratos Vegetais , Complicações Pós-Operatórias , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Aderências Teciduais/etiologia , Aderências Teciduais/patologia
9.
Acta cir. bras ; Acta cir. bras;33(2): 134-143, Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886257

RESUMO

Abstract Purpose: To investigate the effects of pycnogenol on peritoneal adhesions and additionally to investigate the immunohistochemical effects of free oxygen radicals and reactive lymph nodes detected in the adhesive tissue that was sampled surrounding the cecum on intra-abdominal adhesions. Methods: Twenty-seven Wistar Albino rats were divided into three groups. In group 1 (sham), laparotomy was performed and stitched up. In group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered 2 cc of saline. In group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Pycnogenol derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum, and the rats were sacrificed. Results: In group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. Conclusions: No positive outcomes indicating that pycnogenol reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Moreover, a significant increase in lymph node size was detected secondary to inflammation. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, pycnogenol increased the production of free oxygen radicals in the tissue.


Assuntos
Animais , Ratos , Doenças Peritoneais/prevenção & controle , Peritônio/cirurgia , Flavonoides/uso terapêutico , Aderências Teciduais/prevenção & controle , Doenças Peritoneais/etiologia , Peritônio/patologia , Complicações Pós-Operatórias , Flavonoides/efeitos adversos , Imuno-Histoquímica , Extratos Vegetais , Aderências Teciduais/etiologia , Aderências Teciduais/patologia , Espécies Reativas de Oxigênio/metabolismo , Ratos Wistar , Estresse Oxidativo/efeitos dos fármacos , Modelos Animais de Doenças , Radicais Livres/análise , Inflamação/induzido quimicamente , Inflamação/patologia , Laparotomia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico
10.
Int J Mol Sci ; 18(5)2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28467350

RESUMO

Geopropolis is a resin mixed with mud, produced only by stingless bees. Despite being popularly known for its medicinal properties, few scientific studies have proven its biological activities. In this context, the objective of this study was to determine the chemical composition and antioxidant, anti-inflammatory, antimutagenic and antimicrobial activities of the Melipona orbignyi geopropolis. The hydroalcoholic extract of geopropolis (HEGP) was prepared and its chemical composition determined by high performance liquid chromatography coupled to diode array detector and mass spectrometry (HPLC-DAD-MS). The antioxidant activity was determined by the capture of free radicals and inhibition of lipid peroxidation in human erythrocytes. The anti-inflammatory activity was evaluated by the inhibition of the hyaluronidase enzyme and the antimutagenic action was investigated in Saccharomyces cerevisiae colonies. The antimicrobial activities were determined against bacteria and yeasts, isolated from reference strains and hospital origin. The chemical composition of HEGP included flavonoids, derivatives of glycosylated phenolic acids and terpenoids. HEGP showed high antioxidant activity, it inhibited the activity of the inflammatory enzyme hyaluronidase and reduced the mutagenic effects in S. cerevisiae. In relation to the antimicrobial activity, it promoted the death of all microorganisms evaluated. In conclusion, this study reveals for the first time the chemical composition of the HEGP of M. orbignyi and demonstrates its pharmacological properties.


Assuntos
Anti-Infecciosos , Anti-Inflamatórios , Antioxidantes , Abelhas/química , Própole , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Eritrócitos/efeitos dos fármacos , Metanossulfonato de Etila/farmacologia , Flavonoides/análise , Radicais Livres/análise , Humanos , Hialuronoglucosaminidase/efeitos dos fármacos , Hidroxibenzoatos/análise , Peroxidação de Lipídeos/efeitos dos fármacos , Espectrometria de Massas , Mutagênicos , Própole/química , Própole/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos
11.
Vet. Zoot. ; 24(1): 70-83, mar. 2017. ilus
Artigo em Português | VETINDEX | ID: vti-688164

RESUMO

Para que el esperma puede desempeñar sus funciones y lograr el objetivo final, que es la fertilización, requieren energía que proviene de trifosfato de adenosina (ATP). Durante el metabolismo de la energía se almacena en forma de electrones de alta energía que se dirige a la cadena de transporte de electrones, compuesto de cinco proteínas supramolecular. En este proceso, se produce la formación de una, el anión intermedio radical semiquinona (Q- ) que es finalmente capaz de transferir este electrón desapareado a O2 y formar especies reactivas del oxígeno, la superóxido principal, peróxido de hidrógeno y el radical hidroxilo. Estas moléculas son procesos de activación altamente reactivos y espermatozoides que llevan a la degradación y la disminución de la calidad celular. Sin embargo, estas mismas moléculas que a menudo se consideran grandes villanos, también participan en los mecanismos que culminan en la fertilización y la formación de cigoto, adquiriendo así una gran importancia. Con el advenimiento de la criopreservación del semen y el estrés oxidativo asociado con el procesamiento, especies reactivas de oxígeno entraron en evidencia en la investigación, por lo que es necesario estudiar su acción y formas de reducir el estrés oxidativo.(AU)


So that spermatozoa can perform functions and achieve the goal that is fertilization, require energy from adenosine triphosphate (ATP). During the energy metabolism is stored in the form of high-energy electrons that are directed to the electron transport chain, comprised of five supramolecular protein. In this process, there is the formation of a semiquinone anion (Q¯) an intermediate radical that is eventually able to transfer this unpaired electron to O2 and form reactive oxygen species, as the main superoxide, hydrogen peroxide and hydroxyl radical. These molecules are highly reactive and sperm trigger processes that lead to degradation and decrease in cell quality. However these same molecules that are often considered great villains, also participate in mechanisms that culminate in fertilization and zygote formation, thus acquiring great importance. With the advent of semen cryopreservation and oxidative stress associated with the processing, reactive oxygen species entered into evidence in the research, making it necessary to study its action and ways to reduce oxidative stress.(AU)


Para que os espermatozoides possam executar suas funções e alcançarem o objetivo final, que é a fecundação, necessitam de energia que advém da adenosina trifosfato (ATP). Durante o metabolismo, a energia é armazenada na forma de elétrons de alta energia que são direcionados a cadeia de transporte de elétrons, composta de cinco proteínas supramoleculares. Neste processo, há a formação de um radical intermediário, o ânion semiquinona (Q) que eventualmente é capaz de transferir este elétron desemparelhado ao O2 e formar as espécies reativas de oxigênio, sendo as principais o superóxido, o peróxido de hidrogênio e o radical hidroxila. Essas moléculas são altamente reativas e nos espermatozoides desencadeiam processos que levam à degradação e decréscimo na qualidade celular. Porém, essas mesmas moléculas que muitas vezes são consideradas grandes vilãs, também participam de mecanismos que culminam na fertilização e formação do zigoto, adquirindo assim uma grande importância. Com o advento da criopreservação de sêmen e o estresse oxidativo associado ao processamento, as espécies reativas de oxigênio entraram em evidência nas pesquisas, tornando-se necessário o estudo de sua ação e maneiras de reduzir o estresse oxidativo.(AU)


Assuntos
Espermatozoides/fisiologia , Radicais Livres/análise , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/análise , Criopreservação
12.
Vet. zootec ; 24(1): 70-83, mar. 2017. ilus
Artigo em Português | VETINDEX | ID: biblio-1503410

RESUMO

Para que el esperma puede desempeñar sus funciones y lograr el objetivo final, que es la fertilización, requieren energía que proviene de trifosfato de adenosina (ATP). Durante el metabolismo de la energía se almacena en forma de electrones de alta energía que se dirige a la cadena de transporte de electrones, compuesto de cinco proteínas supramolecular. En este proceso, se produce la formación de una, el anión intermedio radical semiquinona (Q- ) que es finalmente capaz de transferir este electrón desapareado a O2 y formar especies reactivas del oxígeno, la superóxido principal, peróxido de hidrógeno y el radical hidroxilo. Estas moléculas son procesos de activación altamente reactivos y espermatozoides que llevan a la degradación y la disminución de la calidad celular. Sin embargo, estas mismas moléculas que a menudo se consideran grandes villanos, también participan en los mecanismos que culminan en la fertilización y la formación de cigoto, adquiriendo así una gran importancia. Con el advenimiento de la criopreservación del semen y el estrés oxidativo asociado con el procesamiento, especies reactivas de oxígeno entraron en evidencia en la investigación, por lo que es necesario estudiar su acción y formas de reducir el estrés oxidativo.


So that spermatozoa can perform functions and achieve the goal that is fertilization, require energy from adenosine triphosphate (ATP). During the energy metabolism is stored in the form of high-energy electrons that are directed to the electron transport chain, comprised of five supramolecular protein. In this process, there is the formation of a semiquinone anion (Q¯) an intermediate radical that is eventually able to transfer this unpaired electron to O2 and form reactive oxygen species, as the main superoxide, hydrogen peroxide and hydroxyl radical. These molecules are highly reactive and sperm trigger processes that lead to degradation and decrease in cell quality. However these same molecules that are often considered great villains, also participate in mechanisms that culminate in fertilization and zygote formation, thus acquiring great importance. With the advent of semen cryopreservation and oxidative stress associated with the processing, reactive oxygen species entered into evidence in the research, making it necessary to study its action and ways to reduce oxidative stress.


Para que os espermatozoides possam executar suas funções e alcançarem o objetivo final, que é a fecundação, necessitam de energia que advém da adenosina trifosfato (ATP). Durante o metabolismo, a energia é armazenada na forma de elétrons de alta energia que são direcionados a cadeia de transporte de elétrons, composta de cinco proteínas supramoleculares. Neste processo, há a formação de um radical intermediário, o ânion semiquinona (Q) que eventualmente é capaz de transferir este elétron desemparelhado ao O2 e formar as espécies reativas de oxigênio, sendo as principais o superóxido, o peróxido de hidrogênio e o radical hidroxila. Essas moléculas são altamente reativas e nos espermatozoides desencadeiam processos que levam à degradação e decréscimo na qualidade celular. Porém, essas mesmas moléculas que muitas vezes são consideradas grandes vilãs, também participam de mecanismos que culminam na fertilização e formação do zigoto, adquirindo assim uma grande importância. Com o advento da criopreservação de sêmen e o estresse oxidativo associado ao processamento, as espécies reativas de oxigênio entraram em evidência nas pesquisas, tornando-se necessário o estudo de sua ação e maneiras de reduzir o estresse oxidativo.


Assuntos
Espermatozoides/fisiologia , Espécies Reativas de Oxigênio/análise , Estresse Oxidativo/fisiologia , Radicais Livres/análise , Criopreservação
13.
Food Chem ; 209: 185-95, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27173551

RESUMO

Chimarrão or mate is a popular beverage from South America that is drank with successive infusions. Although yerba mate extracts have been widely studied, few studies have described the extract contents in beverages. Using yerba mate samples from Brazil, Argentina, and Uruguay, we examined the extract chromatographic profiles, total polyphenol content and their capacities to chelate iron. In addition, we analyzed antioxidant activity by examining the ability of the extracts to scavenge DPPH and NO. Our results showed that the amount of extracted compound was highest in yerba mate extract from Uruguay, followed by Argentina, then Brazil. Herbs from all three areas had a significant capacity to inhibit DPPH and NO free radicals. The Brazilian and Uruguayan herbs had an 80% iron chelation capacity (p<0.001), while the iron chelation capacity of the Argentinean herb was lower but still significant (p⩽0.05). We conclude that the compound concentration decreases with successive extractions, while the antioxidant capacity is maintained at significant levels.


Assuntos
Bebidas/análise , Quelantes/química , Manipulação de Alimentos/métodos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Ferro/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Argentina , Brasil , Quelantes/isolamento & purificação , Radicais Livres/análise , Ilex paraguariensis/química , Polifenóis/química , Polifenóis/isolamento & purificação
14.
Food Chem ; 192: 691-7, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304399

RESUMO

This work proposes the application of batch-injection analysis with amperometric detection to determine the antioxidant capacity of real samples based on the measurement of DPPH radical consumption. The efficient concentration or EC50 value corresponds to the concentration of sample or standard required to scavenge 50% DPPH radicals. For the accurate determination of EC50, samples were incubated with DPPH radical for 1h because many polyphenolic compounds typically found in plants and responsible for the antioxidant activity exhibit slow kinetics. The BIA system with amperometric detection using a glassy-carbon electrode presented high precision (RSD = 0.7%, n = 12), low detection limit (1 µmol L(-1)) and selective detection of DPPH (free of interferences from antioxidants). These contributed to low detection limits for the antioxidant (0.015 and 0.19 µmol L(-1) for gallic acid and butylated hydroxytoluene, respectively). Moreover, BIA methods show great promise for portable analysis because battery-powered instrumentation (electronic micropipette and potentiostats) is commercially available.


Assuntos
Antioxidantes/química , Compostos de Bifenilo/análise , Radicais Livres/análise , Picratos/análise , Antioxidantes/análise , Hidroxitolueno Butilado/análise , Eletrodos , Ácido Gálico/análise , Oxirredução
15.
Biol Res ; 48: 4, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25654191

RESUMO

BACKGROUND: Honey is a natural product obtained from the nectar that is collected from flowers by bees. It has several properties, including those of being food and supplementary diet, and it can be used in cosmetic products. Honey imparts pharmaceutical properties since it has antibacterial and antioxidant activities. The antibacterial and antioxidant activities of Thai honey were investigated in this study. RESULTS: The honey from longan flower (source No. 1) gave the highest activity on MRSA when compared to the other types of honey, with a minimum inhibitory concentration of 12.5% (v/v) and minimum bactericidal concentration of 25% (v/v). Moreover, it was found that MRSA isolate 49 and S. aureus were completely inhibited by the 50% (v/v) longan honey (source No. 1) at 8 and 20 hours of treatment, respectively. Furthermore, it was observed that the honey from coffee pollen (source No. 4) showed the highest phenolic and flavonoid compounds by 734.76 mg gallic/kg of honey and 178.31 mg quercetin/kg of honey, respectively. The antioxidant activity of the honey obtained from coffee pollen was also found to be the highest, when investigated using FRAP and DPPH assay, with 1781.77 mg FeSO4•7H2O/kg of honey and 86.20 mg gallic/kg of honey, respectively. Additionally, inhibition of tyrosinase enzyme was found that honey from coffee flower showed highest inhibition by 63.46%. CONCLUSIONS: Honey demonstrates tremendous potential as a useful source that provides anti-free radicals, anti-tyrosinase and anti-bacterial activity against pathogenic bacteria causing skin diseases.


Assuntos
Apiterapia , Flavonoides/análise , Mel/análise , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Monofenol Mono-Oxigenase , Fenóis/análise , Pólen/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo , Café/química , Flores/química , Recuperação de Fluorescência Após Fotodegradação , Radicais Livres/análise , Mel/classificação , Testes de Sensibilidade Microbiana , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/efeitos dos fármacos , Picratos , Pólen/classificação , Dermatopatias/microbiologia , Dermatopatias/terapia , Preparações Clareadoras de Pele/farmacologia , Tailândia , Fatores de Tempo , Viscosidade
16.
Biol. Res ; 48: 1-11, 2015. graf, tab
Artigo em Inglês | LILACS | ID: lil-734617

RESUMO

BACKGROUND: Honey is a natural product obtained from the nectar that is collected from flowers by bees. It has several properties, including those of being food and supplementary diet, and it can be used in cosmetic products. Honey imparts pharmaceutical properties since it has antibacterial and antioxidant activities. The antibacterial and antioxidant activities of Thai honey were investigated in this study. RESULTS: The honey from longan flower (source No. 1) gave the highest activity on MRSA when compared to the other types of honey, with a minimum inhibitory concentration of 12.5% (v/v) and minimum bactericidal concentration of 25% (v/v). Moreover, it was found that MRSA isolate 49 and S. aureus were completely inhibited by the 50% (v/v) longan honey (source No. 1) at 8 and 20 hours of treatment, respectively. Furthermore, it was observed that the honey from coffee pollen (source No. 4) showed the highest phenolic and flavonoid compounds by 734.76 mg gallic/kg of honey and 178.31 mg quercetin/kg of honey, respectively. The antioxidant activity of the honey obtained from coffee pollen was also found to be the highest, when investigated using FRAP and DPPH assay, with 1781.77 mg FeSO4•7H2O/kg of honey and 86.20 mg gallic/kg of honey, respectively. Additionally, inhibition of tyrosinase enzyme was found that honey from coffee flower showed highest inhibition by 63.46%. CONCLUSIONS: Honey demonstrates tremendous potential as a useful source that provides anti-free radicals, anti-tyrosinase and anti-bacterial activity against pathogenic bacteria causing skin diseases.


Assuntos
Apiterapia , Flavonoides/análise , Mel/análise , Monofenol Mono-Oxigenase , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenóis/análise , Pólen/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo , Café/química , Recuperação de Fluorescência Após Fotodegradação , Flores/química , Radicais Livres/análise , Mel/classificação , Testes de Sensibilidade Microbiana , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/efeitos dos fármacos , Picratos , Pólen/classificação , Dermatopatias/microbiologia , Dermatopatias/terapia , Preparações Clareadoras de Pele/farmacologia , Tailândia , Fatores de Tempo , Viscosidade
17.
Ars Vet. ; 31(1): 1812, 2015.
Artigo em Português | VETINDEX | ID: vti-304357

RESUMO

An imbalance between the antioxidant defense system and the production of reactive oxygen species (ROS) cause oxidative stress, characterized by cellular damage with detrimental effects on sperm quality. The sheep spermatozoa has high susceptibility to oxidative stress and consequently to lipid peroxidation due to higher amount of polyunsaturated fatty acids present in their plasma membrane and the presence of a reduced cytoplasm that maintain low concentrations of antioxidant enzymes. Therefore, it is important to add antioxidants in semen extenders. Some of the endogenous antioxidants present in seminal plasma are catalase (CAT), glutathione peroxidase (GSH) and superoxide dismutase (SOD). The non-enzymatic are: Vitamin E (Tocopherol), Vitamin C and resveratrol. The addition of antioxidants is beneficial in ram semen cryopreservation, however in excess are detrimental as they participate in important stages of the acquisition of sperm fertilizing potential, as training, hyperactivation, acrosome reaction and their interaction with the oocyte(AU)


O desequilíbrio entre o sistema de defesa antioxidante e a produção de espécies reativas de oxigênio (ROS) ocasionam o estresse oxidativo, caracterizado por danos celulares prejudiciais na qualidade espermática. Os espermatozoides de ovinos possuem grande susceptibilidade ao estresse oxidativo e consequentemente à peroxidação lipídica, devido a maior quantidade de ácidos graxos poliinsaturados presentes em sua membrana plasmática e a presença de um citoplasma reduzido que mantêm baixas as concentrações de enzimas antioxidantes. Dessa forma, torna-se importante adicionar substâncias antioxidantes aos meios diluidores do sêmen, que são subdivididas em dois grupos os enzimáticos e não enzimáticos. Dentre os antioxidantes enzimáticos endógenos presentes no plasma seminal destacam-se a catalase (Cat), a glutationa peroxidase (GSH), o superóxido dismutase (SOD) e a cisteína. Já os não enzimáticos são: vitamina E (Tocoferol), vitamina C e resveratrol. A adição dos antioxidantes é vantajosa na criopreservação do sêmen ovino, entretanto em excesso se torna prejudicial, pois participam de importantes fases da aquisição do potencial fertilizante espermático, como a capacitação, hiperativação, reação acrossomal e sua interação com o oócito. Sendo assim a presente revisão visou agrupar os principais antioxidantes, seus malefícios e benefícios na criopreservação do sêmen ovino(AU)


Assuntos
Animais , Ovinos , Antioxidantes/análise , Espécies Reativas de Oxigênio/análise , Estresse Oxidativo , Análise do Sêmen/veterinária , Criopreservação/veterinária , Espermatozoides/fisiologia , Radicais Livres/análise
18.
Ars vet ; 31(1): 1812-18, 2015.
Artigo em Português | VETINDEX | ID: biblio-1463246

RESUMO

An imbalance between the antioxidant defense system and the production of reactive oxygen species (ROS) cause oxidative stress, characterized by cellular damage with detrimental effects on sperm quality. The sheep spermatozoa has high susceptibility to oxidative stress and consequently to lipid peroxidation due to higher amount of polyunsaturated fatty acids present in their plasma membrane and the presence of a reduced cytoplasm that maintain low concentrations of antioxidant enzymes. Therefore, it is important to add antioxidants in semen extenders. Some of the endogenous antioxidants present in seminal plasma are catalase (CAT), glutathione peroxidase (GSH) and superoxide dismutase (SOD). The non-enzymatic are: Vitamin E (Tocopherol), Vitamin C and resveratrol. The addition of antioxidants is beneficial in ram semen cryopreservation, however in excess are detrimental as they participate in important stages of the acquisition of sperm fertilizing potential, as training, hyperactivation, acrosome reaction and their interaction with the oocyte


O desequilíbrio entre o sistema de defesa antioxidante e a produção de espécies reativas de oxigênio (ROS) ocasionam o estresse oxidativo, caracterizado por danos celulares prejudiciais na qualidade espermática. Os espermatozoides de ovinos possuem grande susceptibilidade ao estresse oxidativo e consequentemente à peroxidação lipídica, devido a maior quantidade de ácidos graxos poliinsaturados presentes em sua membrana plasmática e a presença de um citoplasma reduzido que mantêm baixas as concentrações de enzimas antioxidantes. Dessa forma, torna-se importante adicionar substâncias antioxidantes aos meios diluidores do sêmen, que são subdivididas em dois grupos os enzimáticos e não enzimáticos. Dentre os antioxidantes enzimáticos endógenos presentes no plasma seminal destacam-se a catalase (Cat), a glutationa peroxidase (GSH), o superóxido dismutase (SOD) e a cisteína. Já os não enzimáticos são: vitamina E (Tocoferol), vitamina C e resveratrol. A adição dos antioxidantes é vantajosa na criopreservação do sêmen ovino, entretanto em excesso se torna prejudicial, pois participam de importantes fases da aquisição do potencial fertilizante espermático, como a capacitação, hiperativação, reação acrossomal e sua interação com o oócito. Sendo assim a presente revisão visou agrupar os principais antioxidantes, seus malefícios e benefícios na criopreservação do sêmen ovino


Assuntos
Animais , Antioxidantes/análise , Análise do Sêmen/veterinária , Espécies Reativas de Oxigênio/análise , Estresse Oxidativo , Ovinos , Criopreservação/veterinária , Espermatozoides/fisiologia , Radicais Livres/análise
19.
J Mech Behav Biomed Mater ; 36: 82-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24814184

RESUMO

This study evaluated the spin concentration and the crystallinity in different classifications of dental composites as a function of the material condition (new, aged and expired). Specimens were obtained according to the factors: composites: Filtek P60, Filtek Z250, Filtek Z350XT, and Filtek Silorane; and material conditions: new, aged, and expired. The syringe composites underwent an accelerated aging protocol (Arrhenius model). The magnetic properties of the composites were characterized using Electron Paramagnetic Resonance (EPR) and the concentration of spins (number of spins/mass) was calculated. The crystallinity of the composites tested was characterized with X-ray diffraction (XRD). Filtek P60 and Filtek Z250 presented similarities in terms of spin concentration and crystallinity, irrespective of the material condition. The aging protocol influenced the composite Filtek Z350XT that exhibited a significant increase in the spin concentration. Besides, lower intensity peaks of the organic matrix and amorphous silica were also observed for both aged and expired Filtek Z350XT. Although a significant lower spin concentration was observed for the silorane composite in comparison to that of the methacrylates, a decrease in the relative intensity of peaks of the amorphous region related to the organic components in the diffractograms was observed. The material conditions tested influence the crystallinity and the magnetic properties of the composites evaluated.


Assuntos
Resinas Compostas/análise , Resinas Compostas/química , Radicais Livres/análise , Radicais Livres/química , Teste de Materiais/métodos , Modelos Químicos , Algoritmos , Simulação por Computador , Estabilidade de Medicamentos , Conformação Molecular , Propriedades de Superfície , Fatores de Tempo
20.
Biochim Biophys Acta ; 1840(2): 722-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23644035

RESUMO

BACKGROUND: Immuno-spin trapping (IST) is based on the reaction of a spin trap with a free radical to form a stable nitrone adduct, followed by the use of antibodies, rather than traditional electron paramagnetic resonance spectroscopy, to detect the nitrone adduct. IST has been successfully applied to mechanistic in vitro studies, and recently, macromolecule-centered radicals have been detected in models of drug-induced agranulocytosis, hepatotoxicity, cardiotoxicity, and ischemia/reperfusion, as well as in models of neurological, metabolic and immunological diseases. SCOPE OF THE REVIEW: To critically evaluate advances, challenges, and pitfalls as well as the scientific opportunities of IST as applied to the study of protein-centered free radicals generated in stressed organelles, cells, tissues and animal models of disease and exposure. MAJOR CONCLUSIONS: Because the spin trap has to be present at high enough concentrations in the microenvironment where the radical is formed, the possible effects of the spin trap on gene expression, metabolism and cell physiology have to be considered in the use of IST and in the interpretation of results. These factors have not yet been thoroughly dealt with in the literature. GENERAL SIGNIFICANCE: The identification of radicalized proteins during cell/tissue response to stressors will help define their role in the complex cellular response to stressors and pathogenesis; however, the fidelity of spin trapping/immuno-detection and the effects of the spin trap on the biological system should be considered. This article is part of a Special Issue entitled Current methods to study reactive oxygen species - pros and cons and biophysics of membrane proteins. Guest Editor: Christine Winterbourn.


Assuntos
Radicais Livres/análise , Imunoglobulina G/imunologia , Óxidos de Nitrogênio/química , Proteínas/imunologia , Detecção de Spin/métodos , Animais , Bioquímica , Radicais Livres/isolamento & purificação , Humanos , Óxidos de Nitrogênio/imunologia
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