Evaluation of antidiarrhoeal effects of Psidium guajava L. (Myrtaceae) aqueous leaf extract in mice

A crude aqueous extract of the leaves of the guava tree, Psidium guajava L. (Myrtaceae), were studied for antidiarrhoeal effects, to place one of its traditional medical uses. The extract induced a decrease in the propulsive movements of the intestinal contents in mice. These findings suggested that an aqueous extract of guava leaves may be used as an effective treatment for non-specific diarrhoea in folk medicine.

In vivo clastogenicity assessment of the Austroplenckia populnea (Celastraceae) leaves extract using micronucleus and chromosome aberration assay

The clastogenic effect of the A. populnea leaves extract was tested in vivo on bone marrow cells of Wistar rats by evaluating the induction of chromosome aberrations and micronuclei induction on polychromatic erythrocytes. The extract was administered by gavage at doses of 300, 600 and 900mg/kg body weight. Experimental and control animals were submitted to euthanasia 24 h after the treatment. Under the conditions used, A. populnea leaves extract did not induce decrease in mitotic index and did not induce a statistically significant increase in the mean number of micronucleated polychromatic erythrocytes or chromosome aberrations in the bone marrow cells of Wistar rats. © 2007 The Japan Mendel Society.

Vernonia polyanthes as a new source of antiulcer drugs

Methanolic (VPME) and chloroformic (VPCL) extracts, obtained from the aerial parts of Vernonia polyanthes, were investigated for its antiulcerogenic properties. Administration of VPME (250 mg/kg) and VPCL (50 mg/kg) significantly inhibited the gastric mucosa damage (64% and 90%, respectively) caused by absolute ethanol (p.o.). Otherwise, in NSAID-induced gastric damage, their gastroprotective effects have decreased. Since the VPCL extract resulted to be more effective than the VPME we focused our efforts over VPCL action mechanism of action. © 2007 Elsevier B.V. All rights reserved.

Assessment of the potential clastogenic/aneugenic risk of Casearia sylvestris extract using in vivo assays

Casearia sylvestris (Flacourtiaceae) is a plant which grows in wild and has been widely used in folk medicine. In this study, clastogenic/aneugenic properties of Casearia sylvestris crude ethanolic extract were evaluated using in vivo chromosomal aberrations (CAs) and micronucleus (MN) assays in rodents. The animals were treated by gavage with 3 concentrations of the extract: 150, 300 and 500 mg/kg body weight. Bone marrow cells from Wistar rats were collected 24 h after having been submitted to the MN and CAs test. Peripheral blood cells from Swiss mice were collected 48 and 72 h after having been submitted to the MN test. The results show that C. sylvestris extract does not induce a significant increase in mean values for micronucleated polychromatic erythrocytes (MNPCE) in Swiss mice and Wistar rats, or CAs in rat bone marrow cells, at the 3 tested doses, indicating that the extract showed no clastogenic/aneugenic effects on chromosomes of the rodent cells tested. © 2007 The Japan Mendel Society.

Bioprospecção de atividade antioxidante e antimicrobiana da casca de Stryphnodendron adstringens (Mart.) Coville (Leguminosae-Mimosoidae)

The aim of this work was to evaluate the class of secondary metabolites responsible for the antioxidant and antimicrobial activities of bark extracts of Stryphnodendron adstringens (Mart.) Coville (Leguminosae-Mimosoidae), a plant widely used in folk medicine in Brazil. Extracts of the bark were prepared with 50% ethanol, 70% ethanol, acetone:water (7:3, v/v) and chloroform. Antioxidant activity was prospected by spraying thin-layer chromatographs of the extracts with 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and measuring the DPPH radical scavenging capacity by spectrophotometry. Antibacterial activity was revealed by the agar diffusion method and bioautography. TLC spots assigned to tannins in the polar extracts showed antioxidant activity by DPPH radical scavenging and the chloroform extract showed the least scavenging activity. Antimicrobial activity was indicated by the bacterial growth inhibition haloes around polar extracts and bioautography showed activity in the TLC spots assigned to tannins. It was concluded that polar extracts of the bark of S. adstringens possessed antioxidant and antimicrobial activities which were due to secondary metabolite derived from the tannin class, which are the main constituent of these bark extracts, according to the literature.

Antioxidant action of Rosemary extract in soybean oil submitted to thermoxidation

This work was aimed at evaluating the antioxidant activity of rosemary extract added to soybean oil in thermoxidation conditions. Purified soybean oil, refined soybean oil and refined soybean oil containing 1,000 mg/kg rosemary extract were heated at 180°C. The oxidation of the samples was evaluated after 0, 2.5, 5, 7.5 and 10 hours of thermoxidation by means of oxidative stability determination, total polar compounds and conjugated dienes. The purified oil differed significantly from the refined oil, mainly in relation to oxidative stability due the removal of the natural antioxidants. Rosemary extract presented antioxidant effects at high temperatures. After 10 hours of heating, 1,000 mg/kg rosemary extract added to the refined soybean oil significantly increased the oil oxidative stability from 7.52 to 13.5 hours and decreased the formation of polymers and decomposing products measured through the polar rates from 17.35 to 7.99%. The build up of primary oxidation products gauged through diene rates also decreased from 1.61 to 0.80%. Rosemary extract could be recommended as an alternative antioxidant.

Economical analysis of ethanol steam reformer for hydrogen production associated with a sugarcane industry

An expressive amount of produced hydrogen is generated by customers in-situ such as petrochemical, fertilizer and sugarcane industries. However, the most utilized feedstock is natural gas, a non-renewable and fossil fuel. The introduction of biohydrogen production process associated in a sugarcane industry is an alternative to diminish emissions and contribute to create a CO2 cycle, where the plants capture this gas by photosynthesis process and produces sucrose for ethanol production. The cost of production of ethanol has dramatically decreased (from about US$ 700/m3 in 1970s to US$ 200/m3 today), becoming this a good option at near term, inclusively for its utilization by customers localized in main regions (localized especially in regions such as Southeastern Brazil) Also in near future, it will possible the utilization of fuel cells as form of distributed generation. Its utilization could occur specially in peak hours, diminishing the cost of investments in newer transmission systems. A technical and economic analysis of steam reformer of ethanol to hydrogen production associated with sugarcane industry was recently performed. This technique will also allow the use of ethanol when its price is relatively low. This study was based on a previous R&D study (sponsored by CEMIG - State of Minas Gerais Electricity Company) where thermodynamic and economic analyses were developed, based in the development of two ethanol steam reformers prototypes.x In this study an analysis was performed considering the use of bagasse as source of heat in the steam reforming process. Its use could to diminish the costs of hydrogen production, especially at large scale, obtaining cost-competitive production and permitting that sugarcane industry produces hydrogen in large scale beyond ethylic alcohol, anhydrous alcohol (or ethanol) and sugar.

Verificação da atividade antibacteriana de sabonete líquido contendo extrato glicólico de Dimorphandra mollis Benth.

Dimorphandra mollis Benth., Compositae, false barbatimão, has been used topically as a healing, astringent and antibacterial. In this study, antibacterial activity was verified on liquid soap containing glycolic extract of D. mollis (DGE) at different concentrations (8, 15 and 20%) and at different pH levels (6 and 8). Five soap formulations (F) were prepared: F1 - tryclosan (0.1%), F2 - DGE (8%), F3 - DGE (15%), F4 - DGE (20%) and F5 - without preservatives. Bark of D. mollis were dried in a circulating air oven and ground. The rude extracts were prepared by turbo extraction with ethanol. After screening, the extract were concentrated in rotating evaporator, lyophilized and resuspended in propileneglycol to obtain the glycolic extract. The antimicrobial activity was verified by diffusion in agar method, using cylinder in plate. Plates containing Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli were incubated at 37°C for 24 hours. After incubation, the results were analysed with a pachymeter, observing the bacterial grouth inhibition halo diameter. It was verified that the liquid soap containing tryclosan caused on inhibition of bacterial growth at both pH levels; the soaps without preservatives and containing DGE, independently of the concentration and pH levels used, did not present antibacterial activity.

Low caloric value of ethanol itself increases alveolar bone loss in ligature-induced periodontitis in male rats

This study aimed at morphometrically evaluating the influence of variable caloric values of ethanol consumption on alveolar bone loss in periodontitis in male rats. Thirty-six male rats were randomized into four groups of nine rats each, as follows: Test group A (low) - rats were fed an ethanol-containing liquid diet (ethanol representing 22% of total caloric value); Control group A - rats were fed a pair-fed control diet (ethanol replaced by isocaloric amounts of carbohydrate); Test group B (high) - rats were fed an ethanol-containing liquid diet (ethanol representing 36% of total caloric value); Control group B - rats were fed a pair-fed control diet for Test B. Following anesthesia, cotton ligatures were placed around the cervix of the right upper second molar. At eight weeks, the maxillary bones were removed and alveolar bone loss was analyzed by measuring the distance between the cementoenamel junction and the alveolar bone crest at buccal and palatal sites of the upper second molar. The unligated groups showed no significant differences between the bone loss values observed for the low and high caloric values of ethanol (p > 0.05). In the ligated groups, the rats receiving low caloric values of ethanol showed significantly greater bone loss compared to the isocaloric rats (p < 0.05); however, the rats receiving high caloric values of ethanol showed no significant differences compared to the controls. Analysis of the results demonstrated that, in male rats, ethanol itself affected ligature-induced bone loss when representing a low value in the total caloric value.

Oxidative stability and α-tocopherol retention in soybean oil with lemon seed extract (Citrus limon) under thermoxidation

The synergistic effect of lemon seed extract with tert-butylhydroquinone (TBHQ) in soybean oil subjected to thermoxidation by Rancimat was investigated, and the influence of these antioxidants on α-tocopherol degradation in thermoxidized soybean oil. Control, LSE (2,400 mg/kg Lemon Seed Extract), TBHQ (50 mg/kg), Mixture 1 (LSE + 50 mg/kg TBHQ) and Mixture 2 (LSE + 25 mg/kg TBHQ) were subjected to 180°C for 20 h. Samples were taken at time 0, 5, 10, 15 and 20 h intervals and analysed for oxidative stability and α-tocopherol content. LSE and Mixtures 1 and 2 showed the capacity of retarding lipid oxidation when added to soya oil and also contributed to α-tocopherol retention in oil heated at high temperatures. However, Mixtures 1 and 2 added to the oil presented a greater antioxidant power, consequently proving the antioxidants synergistic effect.

rastreamento histoquímico, fitoquímico e biológico de folhas de Plinia cauliflora (DC.) Kausel (Myrtaceae)

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Influence of medium composition in the production of ethanol by Zymomonas mobilis

The production of ethanol using Zymomonas mobilis had been reported to be three to four times larger than with Saccharomyces cereviseae. The influence of pH, temperature and composition of the means of fermentation are parameters that can direct the metabolism for the production of ethanol. The objective of this study was to evaluate the production of ethanol by Zymomonas mobilis CCT 4494, by variations of the initial pH, temperature and concentrations KCl, K 2SO4, MgSO4, CaCl2 and sucrose, by a factorial experimental design of type 27-2, according to the model proposed by Box et al. (1978). For this, the broth of sugar cane was used as sole carbon source, because it is cheap and easily accessible in the region of São José do Rio Preto, São Paulo State. According to the experimental design, the bacteria Zymomonas mobilis CCT 4494 has adapted in the fermentation mean containing high concentrations of sucrose, and supported the change of pH and temperature of fermentation. The highest amount of ethanol produced was 8.89 mg mL-1. This is not similar to the levels of secondary metabolites produced by Zymomonas mobilis CCT 4494.

Effects of physical exercise and cinnamon extract on blood chemistry of type 1 diabetic rats

The present study was designed to analyze the effects of the association between cinnamon extract and aerobic exercise on the glycemic control and serum lipid profile of diabetic rats. Fifty Wistar male rats divided into five groups: control (C), sedentary nondiabetic rats; diabetic (D), sedentary diabetic rats; diabetic cinnamon (DC), sedentary diabetic rats that received cinnamon extract; diabetic exercise (DE), sedentary diabetic rats subjected to physical training; and diabetic cinnamon exercise (DCE), diabetic rats that received cinnamon extract and were subjected to physical training. For the induction of diabetes, the rats received alloxan. The cinnamon was administered to once a day for four weeks. The groups performed swimming exercises for one hour each day with lead overloads (3% - 5% of b.w) for five days a week for four weeks. Body weight loss was lower in the DE group compared to the other diabetic groups. The basal serum glucose of all the diabetic groups was higher compared to the control group. Group D had higher serum cholesterol concentrations compared to the DE and DCE groups. The resting blood lactate in group D was higher than the resting blood lactate in the DC and DE groups. Aerobic exercise partially counteracted the diabetic effects on body weight, serum cholesterol and blood lactate concentrations. No additional beneficial effects of cinnamon extract and aerobic exercise were observed on the parameters studied.

Optimization of a synbiotic formulation of soy yoghurt containing yacon extract by response surface methodology

A synbiotic yoghurt based on a combination of soymilk and yacon water extract (from yacon root tubers) was developed as a novel food product fermented with a probiotic culture of Enterococcus faecium CRL 183 and Lactobacillus helveticus ssp jugurti 4l6. Response surface methodology (RSM) was used to optimize the independent variables soymilk protein concentration and percentage of yacon extract in the formulation through a Central Composite Rotatable Design (CCRD), consisting of a 22 factorial design with two levels (-1, +1), two central points (0) and four axial points (± a, 0) (0, ± α). The responses were assessed by consumer acceptance tests. The optimization indicated that a formulation with a soymilk protein concentration of 1.74g/L and 25.86% of yacon extract gave the best average values, 5.91 for the taste and 6.00 for the overall impression responses. The formulation with 40% of yacon extract and the same concentration of soymilk protein achieved similar acceptance values: taste (5.94) and overall impression (5.87), however, with the extra yacon, it probably had a greater content of prebiotic fructooligosaccharides. Consequently, both formulations may give useful functional foods, with sensory properties comparable with those of soy yoghurt (control formulation). Copyright © 2010 by New Century Health Publishers.

The rise in global demand for ethanol and poverty in Brazil

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