Characterization of condensed tannins from native legumes of the Brazilian northeastern semi-arid

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of lentil tannins on albumin hydrolysis by trypsin

Os taninos da casca da semente de lentilha foram extraídos e purificados, levados à interação com albumina isolada de lentilha e com caseína; e estudados por turbidimetria. As interações da albumina e caseína com taninos purificados, a várias relações tanino-proteína, mostraram ser independente e dependente do pH, respectivamente. Hidrólise in vitro com tripsina das proteínas sem taninos indicou que o aquecimento a 99°C/15 min reduzia a susceptibilidade da albumina e aumentava a da caseína à tripsina. A influência de diferentes relações tanino:proteína (1:40; 1:20; 1:5; 1:2,5) na hidrólise mostrou maior inibição para caseína que para albumina de lentilha, independente de aquecimento. Após aquecimento ambas proteínas foram mais hidrolizadas para qualquer das relações tanino proteínas estudadas. A eletroforese em gel de poliacrilamida-dodecilsulfato de sódio do transcurso da hidrólise da interação tanino-albumina nativa mostra a dependência da relação tanino:proteína.

Effect of Mouriri pusa tannins and flavonoids on prevention and treatment against experimental gastric ulcer

Aim of the study: Mouriri pusa, popularly known as manapuca or jaboticaba do mato, is a plant from Brazilian cerrado that has been found to be commonly used in the treatment of gastrointestinal disturbs in its native region. The present work was carried out to investigate the effect of tannins (TF) and flavonoids (FF) fractions from Mouriri pusa leaves methanolic extract on the prevention and cicatrisation process of gastric ulcers, and also evaluate possible toxic effects.Materials and methods: The following protocols were taken in rats: acute assay, in which ulcers were induced by oral ethanol after pre-treatment with the fractions; and 14 days treatment assay, in which ulcers were treated for 14 days after induction by local injection of acetic acid.Results: In the acute model, treatment with either, TF (25 mg/kg) or FF (50 mg/kg), was able to reduce lesion area, showing gastroprotective effect. In addition, FF proved itself anti-inflammatory by reducing COX-2 levels. In acetic acid model, both fractions exhibited larger ulcers' regenerative mucosa, indicating cicatrisation enhancement. FF group also showed augmented cell proliferation, anti-inflammatory action and enhanced angiogenesis as well as increased mucus secretion. Moreover, concerning the toxicity parameters analyzed, no alteration in the fractions groups was observed.Conclusions: Tannins and flavonoids from Mouriri pusa provide beneficial effects against gastric ulcers with relative safety. (C) 2010 Elsevier B.V. All rights reserved.

Do all tannins have similar nutritional effects? A comparison of three Brazilian fodder legumes

Three tropical legumes, namely Leucaena leucocephala, Sesbania sesban and Cajanus cajan, were subjected to chemical analysis plus in vitro, in situ and in vivo evaluations. Three different assays were used to determine total tannins: adsorption to polyvinyl pyrrolidine (PVPP-tannins), radial diffusion (RD-tannins) and protein precipitation capacity (BSA-tannins). Total phenols, total tannins and condensed tannins were highest for Sesbania. RD-tannins were correlated with total phenols (r(2) = 0.93), PVPP-tannins (r(2) = 0.92) and condensed tannins (r(2) = 0.99). The protein precipitation capacity of Sesbania, Leucaena and Cajanus were 25.9, 6.13 and 4.05 mu g BSA/g DM, respectively.Gas production at 24h was negatively correlated with total phenols (r(2) = 0.99), PVPP-tannins (r(2) = 0.99) and condensed tannins (r(2) = 0.91). The RD-, PVPP-tannins and the response to polyethylene glycol (PEG) in the gas production assay appeared to be useful as a first screen for tannins.In situ degradability did not reflect any adverse effects of tannins. However, in vivo experiments showed that the apparent DM digestibility of Sesbania and Leucaena was lower than the basal diet. The apparent protein digestibility was lower for all legumes compared to the basal diet. Most treatments caused a negative nitrogen balance. The problems associated with browse feeding were not only related to tannin contents, other factors such as inherently poor digestibility and low energy intake may also have lead to the poor animal performance on these diets. We propose, given the limitations of current tannin assays, that it is not possible to predict beneficial or harmful nutritional effects from total tannin concentrations per se. (C) 2004 Elsevier B.V. All rights reserved.

Influence of condensed tannins from Brazilian semi-arid legumes on ruminal degradability, microbial colonization and ruminal enzymatic activity in Saanen goats

The present study aimed at determining the influence of condensed tannins present in the Brazilian legume species Mimosa hostilis, Mimosa caesalpinifolia and Bauhinia cheilantha on ruminal degradability, microbial colonization and enzymatic activity. Polyethylene glycol (PEG) was used to reduce the astringency and concentration of soluble condensed tannins. Four ruminally-cannulated Saanen goats (60 +/- 8 kg BW) were fed, in two experimental periods, with a hay diet based on the studied legumes treated or non-treated with PEG. Voluntary intake, microbial colonization, DM, CP, NDF, and ruminal degradability of PEG treated and non-treated forage leaves, as well as pH, ammonia and 1,4 P-endoglucanase activity of the rumen content were evaluated. Astringency and soluble tannin concentration of the studied legumes were reduced by approximately 70% and 50%, respectively, with PEG treatment. Average DM intake was higher for the treated diet (16.76 g DM/kg BW/day against 13.06 g DM/kg BW/day). Percentile values for degradation parameters and for potential and effective degradabilities of DM, CP and NDF were also affected by the tannins, but at different intensities. Electron microscopic observations of ruminally-incubated legume leaves showed a more effective microbial colonization of PEG-treated leaves for all legume species. A decrease in pH and an increase in ammonia concentration and in endoglucanase activity in the ruminal content was also observed for PEG-treated diets at all sampling periods. Condensed tannins of the studied legume species have influenced the adhesion conditions, colonization and enzymatic activity of the microbial ecosystem, and consequently the ruminal degradation of the different dietary fractions. For this reason, the reduction in condensed tannin would be of great importance to improve the nutrition of ruminant feeding of these species. (c) 2005 Elsevier B.V. All rights reserved.

Anthocyanins and tannins in ozone-fumigated guava trees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anthelmintic effects of condensed tannins on Trichostrongylus colubriformis in experimentally infected sheep

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anthelmintic effect of plant extracts containing condensed and hydrolyzable tannins on Caenorhabditis elegans, and their antioxidant capacity

Although tannin-rich forages are known to increase protein uptake and to reduce gastrointestinal nematode infections in grazing ruminants, most published research involves forages with condensed tannins (CT), while published literature lacks information on the anthelmintic capacity, nutritional benefits, and antioxidant capacity of alternative forages containing hydrolyzable tannins (HT). We evaluated the anthelmintic activity and the antioxidant capacity of plant extracts containing either mostly CT, mostly HT, or both CT and HT. Extracts were prepared with 70% acetone, lyophilized, redissolved to doses ranging from 1.0mg/mL to 25mg/mL, and tested against adult Caenorhabditis elegans as a test model. The extract concentrations that killed 50% (LC50) or 90% (LC90) of the nematodes in 24h were determined and compared to the veterinary anthelmintic levamisole (8mg/mL). Extracts were quantified for CT by the acid butanol assay, for HT (based on gallic acid and ellagic acid) by high-performance liquid chromatography (HPLC) and total phenolics, and for their antioxidant activity by the oxygen radical absorbance capacity (ORAC) assay. Extracts with mostly CT were Lespedeza cuneata, Salix X sepulcralis, and Robinia pseudoacacia. Extracts rich in HT were Acer rubrum, Rosa multiflora, and Quercus alba, while Rhus typhina had both HT and CT. The extracts with the lowest LC50 and LC90 concentrations, respectively, in the C. elegans assay were Q. alba (0.75 and 1.06mg/mL), R. typhina collected in 2007 (0.65 and 2.74mg/mL), A. rubrum (1.03 and 5.54mg/mL), and R. multiflora (2.14 and 8.70mg/mL). At the doses of 20 and 25mg/mL, HT-rich, or both CT- and HT-rich, extracts were significantly more lethal to adult C. elegans than extracts containing only CT. All extracts were high in antioxidant capacity, with ORAC values ranging from 1800μmoles to 4651μmoles of trolox equivalents/g, but ORAC did not correlate with anthelmintic activity. The total phenolics test had a positive and highly significant (r=0.826, p≤0.01) correlation with total hydrolyzable tannins. Plants used in this research are naturalized to the Appalachian edaphoclimatic conditions, but occur in temperate climate areas worldwide. They represent a rich, renewable, and unexplored source of tannins and antioxidants for grazing ruminants, whereas conventional CT-rich forages, such as L. cuneata, may be hard to establish and adapt to areas with temperate climate. Due to their high in vitro anthelmintic activity, antioxidant capacity, and their adaptability to non-arable lands, Q. alba, R. typhina, A. rubrum, and R. multiflora have a high potential to improve the health of grazing animals and must have their anthelmintic effects confirmed in vivo in both sheep and goats. © 2012.

Avaliação da influência de substâncias fenólicas e carotenoides na anomalia do epicarpo da goiaba, anelamento

A anomalia do epicarpo da goiaba, comumente relatada por agricultores e técnicos como o anelamento juvenil da goiaba, tem causado preocupação devido à desinformação sobre o assunto. O objetivo deste estudo foi analisar quimicamente as concentrações de substâncias fenólicas e carotenoides na região do epicarpo de goiabas afetadas pelo anelamento, visando a caracterizar essa anomalia previamente relatada. Foram analisadas substâncias fenólicas (taninos, flavonas/flavonóis, antocianinas e fenóis totais) e carotenoides em epicarpos de frutos verdes e maduros de goiabeiras cv. Paluma, com e sem anomalia. O delineamento experimental adotado foi o inteiramente casualizado, sendo estabelecidos seis tratamentos com o epicarpo dos frutos maduro sem anomalia na região inferior (FMSI); frutos maduros sem injuria na região superior (FMSS); frutos verdes sem anomalia na região inferior (FVSI); frutos verdes sem anomalia na região superior (FVSS); frutos verdes com anomalia na região inferior (FVCI); frutos verdes com anomalia na região superior (FVCS). Dentre as substâncias analisadas, os carotenoides, os taninos e os fenóis totais mostram indicativos para a caracterização do anelamento. Tanto substâncias fenólicas quanto carotenoides apresentam propriedades antioxidantes e, dessa forma, poderiam estar relacionadas à defesa antioxidante causada por um fator de estresse ainda desconhecido, que promove o anelamento característico apresentado pelas goiabas.

Efeito dos taninos condensados de forrageiras nativas do semi-árido nordestino sobre o crescimento e atividade celulolítica de Ruminococcus flavefaciens FD1

Avaliaram-se o crescimento da população, a atividade in vitro da enzima 1,4-b-endoglucanase e a taxa de digestão de celulose em culturas de Ruminococcus flavefaciens FD1 na presença de 50, 100, 200 e 400µg/ml de taninos purificado das leguminosas Mimosa hostilis (Jurema Preta), Mimosa caesalpinifolia (Sabiá) e Bauhinia cheilantha (Mororó). O crescimento bacteriano, a atividade da endoglucanase e a digestão de celulose foram fortemente inibidos pela presença dos taninos condensados purificados das três espécies, entretanto, a intensidade da inibição foi variável em função da espécie da leguminosa e da concentração de tanino.

Evidence of ecotypic differentiation between populations of the tree species Parapiptadenia rigida due to flooding

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo fitoquímico de goiaba (Psidium guajava L.) com potencial antioxidante para o desenvolvimento de formulação fitocosmética

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mutagenicity induced by the hydroalcoholic extract of the medicinal plant Plathymenia reticulata Benth

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mutagenicity of Mouriri pusa Gardner and Mouriri elliptica Martius

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of extracts of Stryphnodendron polyphyllum Mart. and Stryphnodendron obovatum Benth. on the cicatrisation of cutaneous wounds in rats

Stem bark of the two species Stryphnodendron polyphyllum Mart. and Stryphnodendron obovatum Benth., Leguminosae, was investigated for wound healing, antibacterial and antioxidant activity. These plants contain 12 and 19% tannins in their stem bark, respectively, and are widely used in traditional medicine in Brazil. The total content of phenolics of the crude extract (CE) of Stryphnodendron obovatum was 76.95 +/- 2.98% (CV = 3.87%) and of the ethyl-acetate fraction (EAF) was 89.13 +/- 0.34% (CV = 0.38%); whereas in Stryphnodendron polyphyllum the CE phenolics content was 51.62 +/- 1.53% (CV = 2.96%) and the EAF phenolics content was 59.00 +/- 1.91% (CV = 3.24%). The tannin content of CE from Stryphnodendron obovatum [36.58 +/- 0.35% (CV = 0.98%)] was about 11% higher than in CE from Stryphnodendron polyphyllum [25.43 +/- 0.96% (CV = 3.77%)]. The difference between the species was even greater in the EAF: in Stryphnodendron obovatum the EAF phenolics content was 55.01 +/- 0.36% (CV = 0.65%), whereas in Stryphnodendron polyphyllum the content was 36.16 +/- 0.42% (CV = 1.16%). The healing effect of ointments containing 2.5% crude lyophilised extract (PCE) and 2.5% ethyl-acetate lyophilised fraction (PEA) of the stem bark of Stryphnodendron polyphyllum and Stryphnodendron obovatum was studied in cutaneous wounds of Wistar((R)) rats after 4, 7 and 10 days of treatment. Epithelial cell proliferation in the area of re-epithelialisation of the wounds was evaluated by counting the metaphases blocked by vincristine sulfate. With PCE an increase in epidermal growth was observed after 4 and 7 days of treatment with Stryphnodendron polyphyllum, and after 7 and 10 days of treatment with Stryphnodendron obovatum. Wounds treated with PEA of Stryphnodendron obovatum showed increased epidermal growth only 4 days after the treatment, for Stryphnodendron polyphyllum, epidermal growth was observed after 4 and 7 days of treatment. Both the CE and the EAF fractions of Stryphnodendron polyphyllum and Stryphnodendron obovatum showed antibacterial activity against Staphylococcus aureus with MIC values of 125 and 250 mu g/ml, respectively. Gram-negative bacteria tested were not inhibited by extracts and fractions at concentrations > 1000 mu g/ml. The antioxidant activity through reduction of the DPPH radical in TLC, confirmed the anti-radical properties of these extracts in both species. CE and EAF of both species showed a radical scavenging activity (RSA) and protected DPPH from discolouration, already at 0.032 mu g/ml. The extract from Stryphnodendron polyphyllum were more effective than those Stryphnodendron obovatum, although the former had a lower tannin content. (c) 2005 Elsevier B.V.. All rights reserved.