Antimicrobial and antioxidant activities of Enterococcus species isolated from meat and dairy products / Atividade antimicrobiana e antioxidante de espécies de Enterococcus isoladas de carne e produtos lácteos

Abstract Lactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faecium species. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.

Resumo As bactérias ácido láticas (BAL) têm um papel importante em uma grande variedade de alimentos fermentados. Em adição à sua contribuição para as características sensoriais, estes microorganismos melhoram a conservação de alimentos e podem ser utilizados como probióticos. Neste estudo, as atividades antimicrobiana e antioxidante do sobrenadante e dos extratos livres de células de 16 isolados de LAB de carne e produtos lácteos foram investigadas. Os isolados foram identificados pelo sequenciamento da região 16S do rRNA. Após a comparação das sequências obtidas com aquelas disponíveis na base de dados GenBank, observou-e que todos os isolados foram pertencentes à espécie Enterococcus faecium. A atividade antimicrobiana contra o microrganismo indicador (Listeria monocytogenes) foi observada no sobrenadante das culturas em 11 isolados, e nos extratos livres de células por 4 isolados. A sensibilidade da cultura sobrenadante foi avaliada pela proteinase K e tripsina e observou-se que a atividade da substância antimicrobiana foi completamente perdida após o tratamento com as enzimas proteolíticas. Todos os isolados apresentaram atividade antioxidante, como determinado pelo método do ácido tiobarbitúrico de substâncias reativas (TBARS) com ambos os tipos de extratos. Quando a capacidade antioxidante foi investigada usando o método do ABTS (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) e o método de DPPH (2,2-diphenyl-1-picrylhydrazyl) observou-se que apenas os sobrenadantes das culturas demonstraram capacidade antioxidante. Estas bactérias poderiam particularmente ajudar a reduzir ou inibir microorganismos patogênicos, bem como a deterioração oxidativa em alimentos e rações.

Apoptosis and oxidative stress in b thalassemia major in children

In B thalassemia the synthesis of beta globin chains is decreased .This interferes with the assembly of normal Hb A,. Recently apoptosis has been noted to play a central role in regulation of hemopieosis. Excess iron could generate reactive oxygen species [ROS] that may be involved in turn in lie damage of cellular compartment adding to apoptosis . The aim of this work is to study apoptosis and oxidative stress in B thalassemia major in children and their relationship to the severity of the disease and to the use of chelation . A cross sectional study of 56 patients with B thalassemia major aged 8 M -13 y as well as 10 apparently healthy age and sex- matched control . Beside full history and examination all patients and controls had the following investigations done Hb, serum ferritin, ALT, AST, ALP, FAS, TBARS and DNA damage measurement. Correlation studies showed that fas and TBARS showed significant negative correlation with Hb and significant positive correlation with ferritin . Newly diagnosed patients [First admission] showed significantly less severe DNA damage than recurrent cases . Chelated patients scored significantly better lhan non chelated patients . Patients on chelation showed significant better outcome regarding apoptosis and oxidative stress, therefore we must be ready with early chelation in all B thalassemia cases

nutritional, glutathione and oxidant status of elderly subjects admitted to a university hospital

Malnutrition in elderly patients is common in hospitals, and many of the age associated chronic diseases have a common factor, which is oxidative stress. The aim of the study was to evaluate the nutritional status, glutathione, and oxidant status of elderly patients. The mini-nutritional assessment [MNA] was used to determine the nutritional status of elderly patients. Glutathione concentration in the whole blood, plasma albumin, and thiobarbituric acid-reactive substances [TEARS] levels was measured spectrophotometrically by the enzymatic recycling method. In addition, length of hospital stay was estimated. All measurements were taken within 48 h after admission. The results showed that more than two-thirds of the elderly were classified as at risk of malnutrition and malnourished. About 45% and 53% elevation in the TEARS was found in at risk of being malnourished and in the malnourished groups, respectively, compared to the well-nourished group, but the elevation did not reach the significant level. No significant differences in the glutathione concentration and in the length of hospital stay were found among the three mini-nutritional assessment categories. The study indicated the necessity of performing the MNA test for elderly upon admission to hospitals, and more attention needs to be paid to this vulnerable group of people

Anti-hyperglycemic and anti-oxidative effect of aqueous extract of Momordica charantia pulp and Trigonella foenum graecum seed in alloxan-induced diabetic rats.

Diabetes is an oxidative stress disorder and oxidative damage to tissues such as heart, kidney, liver and other organs may be a contributory factor to several diabetic complications. Momordica charantia (family: Cucurbitaceae) and Trigonella foenum graecum (family: Fabaceae) are used traditionally in Indian folk medicine to manage diabetes mellitus. In the present study, the anti-hyperglycemic and anti-oxidative potential of aqueous extracts of M. charantia pulp and seed powder of T. foenum graecum were assessed in alloxan (150 mg/kg body weight) induced diabetic rats. Alloxan treatment to the rats could induce diabetes as the fasting blood glucose (FBG) levels were >280 mg/dl. Treatment of diabetic rats for 30 days with M. charantia and T. foenum graecum could significantly (p<0.001) improve the FBG levels to near normal glucose levels. Antioxidant activities (superoxide dismutase, catalase, reduced glutathione content and glutathione-s-transferase) and lipid peroxidation levels were measured in heart, kidney and liver tissues of normal, diabetic and experimental animals (diabetics + treatment). TBARS levels were significantly (p<0.001) higher and anti-oxidative activities were found low in diabetic group, as compared to the control group. Significant (p<0.001) improvement in both the TBARS levels and antioxidant activities were observed when M. charantia and T. foenum graecum were given to diabetic rats. Our results clearly demonstrate that M. charantia and T. foenum graecum are not only useful in controlling the blood glucose levels, but also have antioxidant potential to protect vital organs such as heart and kidney against damage caused due to diabetes induced oxidative stress.

Efficacy of Setarud (IMOD®), a novel drug with potent anti-toxic stress potential in rat inflammatory bowel disease and comparison with dexamethasone and infliximab.

The inflammatory bowel disease (IBD) is an idiopathic, immune-mediated and chronic intestinal condition. In the present study, the effect of Serarud (IMOD®), a novel natural drug with known immunomodulatory, anti-inflammatory and antioxidant properties was investigated in experimental colitis in rats and compared with the dexamethasone and infliximab. Immunologic colitis was induced by intracolonic administration of a mixture of trinitrobenzene sulfonic acid (TNBS) and absolute ethanol in male Wistar rats. Animals were divided into 6 groups of sham (normal group), control (vehicle-treated), positive control (dexamethasone 1 mg/kg/day given orally and infliximab 5 mg/kg/day given subcutaneously) and 3 Setarud-treated groups (13.3, 20, 30 mg/kg/day given intraperitoneally). The treatment continued for 14 consecutive days and then animals were decapitated on the day 15 and distal colons were removed for macroscopic, microscopic, and biochemical assays. Biochemical markers, including TNF-, IL-1, ferric reducing/antioxidant power (FRAP), myeloperoxidase (MPO) activity and thiobarbitoric acid-reactive substance (TBARS) were measured in the homogenate of colonic tissue. A remarkable reduction in macroscopic and histological damage scores was observed in the animals treated with Setarud. These findings were confirmed by decreased levels of TNF-, interleukin-1, MPO activity and TBARS, and raised levels of FRAP in the colon tissue. These observations confirmed the immunomodulatory, anti-inflammatory and antioxidant properties of Setarud in experimental colitis, which was comparable to those of dexamethasone and infliximab.

Mechanism, measurement, and prevention of oxidative stress in male reproductive physiology.

Numerous factors influence male fertility. Among these factors is oxidative stress (OS), which has elicited an enormous interest in researchers in recent period. Reactive oxygen species (ROS) are continuously produced by various metabolic and physiologic processes. OS occurs when the delicate balance between the production of ROS and the inherent antioxidant capacity of the organism is distorted. Spermatozoa are particularly sensitive to ROS as their plasma membrane contains polyunsaturated fatty acids (PUFA), which oxidizes easily. They also lack cytoplasm to generate a robust preventive and repair mechanism against ROS. The transition metal ions that are found in the body have a catalytic effect in the generation of ROS. Lifestyle behaviours such as smoking and alcohol use and environmental pollution further enhance the generation of ROS and thus, cause destructive effects on various cellular organelles like mitochondria, sperm DNA etc. This article analyzes the detrimental effects of OS on male fertility, measurement of OS and effective ways to decrease or eliminate them completely. We have also provided information on oxidative stress in other systems of the body, which may be applied to future research in the field of reproductive biology.

Anticonvulsant and hypnotic agents: novel thiobarbituric acid derivatives of 4 [3H] -quinazolines

5 novel series of 4[3H]-quinazolinone derivatives have been prepared: 2-methyl/phenyl-3-[3-substituted-4,6-dioxo-2-thioxohexahydropyrimidin- 1-yl]-4[3H]-quinazolinones [IIIa]; 2-phenyl-3-[3-aryl-5-benzylidene- 4,6-dioxo-2-thioxohexahydropyrimidin-1-yl]-4[3H]-quinazolinones [IVa- c]; 3-aryl-2-[3-aryl,-4,6-dioxo-2-thioxohexahydropyrimidin-1-yl] -iminomethyl-4[3H]-quinazolinones [VIa-f]; 3-aryl-2-[3-aryl-5- benzylidene-4,6-dioxo-2-thioxohexahydropyrimidin-1-yl] iminomethyl-4- [3H]-quinazolinones [VIIa-f] and 3-aryl-2-[3-[3-aryl-4,6-dioxo-2-thioxohexahydropyrimidin-1-yl]-4-oxo- 1,3-thiazolidin-2-yl]-4[3-H]-quinazolinones [VIIIa-f]. Some products showed anticonvulsant and hypnotic activities when tested in mice