Evaluation of the spouted bed dried leaf extract of Bauhinia forficata for the treatment of experimental diabetes in rats

Previously, we have demonstrated that treatment of experimental diabetes with a decoction of Bauhinia forficata leaves is beneficial. In this study, we prepared a two-fold concentrate of this extract and tested its effects on physiological, biochemical and toxicity markers in streptozotocin-diabetic rats. Dried and ground leaves were extracted with warm 70% hydroethanol and the filtrate concentrated by evaporation at 50 degrees C. This solution was mixed with colloidal silicon dioxide (Tixosil-333 (R)) and dried in a spouted bed (BfT). Rats were treated with water, insulin and Tixosil particles at low or high doses, alone or coated with dried BfT. Animals were periodically weighed and monitored for water and food intake; urinary volume, glucose, urea and protein; blood glucose, serum lipids, liver toxicity markers transaminase and phosphatase and masses of adipose tissue and skeletal muscle. Insulin treatment gave best rat growth and lowest values for all other markers. No other treatment affected any diabetic marker, but the enzyme activities were changed by diabetes and BfT. Thus, BfT toxicity could arise from secondary products of plant constituents or Tixosil interaction. Therefore, BfT prepared in the spouted bed as described, is unsuitable for treatment of diabetes, which implies that the method of preparation of any medicine is critical for its efficacy and toxicity.

Parâmetros bioquímicos foliares das espécies Licania tomentosa (Benth.) e Bauhinia forficata (Link.) para avaliação da qualidade do ar

Foliar analysis of biochemical parameters were carried out in order to investigate the influence of air pollutants on two tropical tree species (Licania tomentosa (Benth.) and Bauhinia forfícata (Link.)). Special attention was given to tropospheric ozone due to the fact that concentration levels in the region were found to be up to 140 µg m-3 for a 4 h average time, which is well above the value that can cause injuries to orchides and tobacco (59 µg m-3). Other pollutants such as nitrogen and sulphur oxides were measured and their ambient concentrations were also associated to biochemical alterations in the investigated species.

Sucrose metabolizing enzymes in cell suspension cultures of Bauhinia forficata, Curcuma zedoaria and Phaseolus vulgaris

The objective of this work was to study the activity of sucrose metabolizing enzymes in extracts of cell suspension cultures of Bauhinia forficata Link, Curcuma zedoaria Roscoe and Phaseolus vulgaris L. Invertase pathway was identified in the three studied species. Sucrose synthase pathway was also responsible for sucrose metabolism in Curcuma zedoaria and Phaseolus vulgaris cells. Activity values higher than 300 nmol min-1 mg-1 of protein were found for acid and neutral invertases, UDPglucose pyrophosphorylase and phosphoglucomutase in the cell extract of the three plant species. Sucrose synthase showed low activity in Bauhinia forficata cells. As sucrose concentration in the culture medium decreased, sucrose synthase activity increased in C. zedoaria and P. vulgaris cells. The glycolytic enzymes activity gradually reduced at the end of the culture period, when carbohydrate was limited.

Flavonóides glicosilados das folhas e flores de Bauhinia forficata (Leguminosae)

From the leaves of Bauhinia forficata kaempferol and four flavonoid glycosides, 3,7-di-O-alpha-L-rhamnopyranosylkaempferol, 3,7-di-O-alpha-L-rhamnopyranosylquercetin, 3-O-[alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranosyl]-7-O-alpha-L-rhamnopyranosylkaempferol and 3-O-[alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranosyl]-7-O-alpha-L-rhamnopyranosylquercetin were obtained. From the flowers only the flavonoid 7-O-alpha-L-rhamnopyranosylkaempferol was isolated. The structures were established by chemical and spectroscopic methods.

Parâmetros bioquímicos foliares das espécies Licania tomentosa (Benth.) e Bauhinia forficata (Link.) para avaliação da qualidade do ar

Foliar analysis of biochemical parameters were carried out in order to investigate the influence of air pollutants on two tropical tree species (Licania tomentosa (Benth.) and Bauhinia forfícata (Link.)). Special attention was given to tropospheric ozone due to the fact that concentration levels in the region were found to be up to 140 µg m-3 for a 4 h average time, which is well above the value that can cause injuries to orchides and tobacco (59 µg m-3). Other pollutants such as nitrogen and sulphur oxides were measured and their ambient concentrations were also associated to biochemical alterations in the investigated species.

Avaliação de procedimentos para quantificação espectrofotométrica de flavonoides totais em folhas de Bauhinia forficata Link

Interest in analytical methods for quality control of herbal drugs has grown sharply due to the scarcity of monographs in official manuals. Thus, the aim of the present study was to evaluate analytical procedures for quantitative determination of flavonoids from leaves of Bauhinia forficata Link (pata-de-vaca). Two procedures for quantification of total flavonoids (with and without acid hydrolysis) by spectrophotometry were tested. The proposed methods proved to be specific, sensitive, precise, accurate and robust, being suitable for routine laboratory use.

Determinação química e biológica de bauhinia forficata link subespécie pruinosa (pata-de-vaca - leguminosae)

Bauhinia forficata, Leguminosae, é conhecida popularmente como pata-devaca e seus principais constituintes químicos são flavonóides. Ë comumente usada como antidiabética, mas existem relatos a respeito de suas atividades antioxidante e antiedematogênica. A fim de avaliar-se o comportamento de seus constituintes químicos frente a variações de temperatura e umidade, realizou-se estudo de estabilidade acelerada (50 ºC ± 2 oC e 90% ± 5% U.R.), onde a substância química majoritária (SQM) serviu como marcador para os devidos cálculos e, portanto, o seu isolamento prévio tornou-se imprescindível. Um método devidamente validado por Cromatografia Líquida de Alta Eficiência (CLAE) foi utilizado para as análises e através das mesmas pode-se predizer uma reação de segunda ordem e, por conseguinte, um tempo de vida útil de 2,63 dias e um tempo de meia-vida de 23,65 dias. Avaliou-se, ainda, as atividades antioxidante (DPPH), antiedematogênica (edema em pata de ratos induzido pela carragenina) e anticolinesterásica (autobiografia). Para a atividade antioxidante, dos extratos testados, o butanólico foi o que demonstrou maior ação (54,73 µl/ml) sendo, no entanto, inferior ao padrão Ginkgo biloba (42,51 µl/ml). Na avaliação da atividade antiedematogênica, o extrato aquoso testado demonstrou um máximo de inibição de 76,5%. Ao testar-se a atividade anticolinesterásica de produtos isolados obtidos a partir de B. forficata, nenhuma ação significativa foi observada exigindo estudos complementares.

Ocorrência de Oídio (Oidium caesalpiniacearum Hosag & W. Braum) em Pata de Vaca (Bauhinia forficata link.) no Brasil

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

Free radical scavenging profile and myeloperoxidase inhibition of extracts from antidiabetic plants: Bauhinia forficata and Cissus sicyoides

There is abundant evidence that reactive oxygen species are implicated in several physiological and pathological processes. To protect biological targets from oxidative damage. antioxidants must react with radicals and other reactive species faster than biological substrates do. The aim of the present study was to determine the in vitro antioxidant activity of aqueous extracts from leaves of Bauhinia forficata Link (Fabaceae - Caesalpinioideae) and Cissus sicyoides L. (Vitaceae) (two medicinal plants used popularly in the control of diabetes mellitus), using several different assay systems, namely, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) decolorization. superoxide anion radical (O-2 center dot-) scavenging and myeloperoxidase (MPO) activity. In the ABTS assay for total antioxidant activity, B. forficata showed IC50 8.00 +/- 0.07 mu g/mL, while C. sicyoides showed IC50 13.0 +/- 0.2 mu g/mL. However, the extract of C. sicyoides had a stronger effect on O-2 center dot- (IC50 60.0 +/- 2.3 mu p/mL) than the extract of B. forficata (IC50 90.0 +/- 4.4 mu g/mL). B. forficata also had a stronger inhibitory effect on MPO activity, as measured by guaiacol oxidation, than C. sicyoides. These results indicate that aqueous extracts of leaves of B. forficata and C. sicyoides are a potential source of natural antioxidants and may be helpful in the prevention of diabetic complications associated with oxidative stress.

Evaluation of the spouted bed dried leaf extract of Bauhinia forficata for the treatment of experimental diabetes in rats

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

Anti-diabetic activity of Bauhinia forficata decoction in streptozotocin-diabetic rats

The effects of using Bauhinia forficata leaf decoction (150 g leaf/l water; 35.2+/-7.8 ml/100 g body weight mean daily dose) as a drinking-water substitute for about I month on streptozotocin-diabetes (STZ-diabetes) in male Wistar rats were investigated. The physico-metabolic parameters measured were: body weight, food and liquid intake, urinary volume, hepatic glycogen, serum triglycerides and cholesterol, plasma glucose, urinary glucose and urea, and the weight of epididymal and retroperitoneal adipose tissue and soleus and extensor digitorum longus muscles. The STZ-diabetic rats treated with decoction showed a significant reduction in serum and urinary glucose and urinary urea as compared to the STZ-diabetic control, no difference being seen between decoction-treated and -untreated non-diabetic rats. The other physico-metabolic factors showed no changes in treated STZ-diabetic rats. The improvement in carbohydrate metabolism seen in the rats treated with Bauhinia forficata decoction does not appear to be linked to the inhibition of glycogenolysis or the stimulation of glycogenesis nor does it appear to act in a way similar to insulin or the sulfonylureas, although it may act by the inhibition of neoglycogenesis in a manner similar to that of the biguanides. (C) 2002 Elsevier B.V. Ireland Ltd. All rights reserved.

Effect of Bauhinia forficata extract in diabetic pregnant rats: maternal repercussions

Bauhinia forficata, commonly known as paw-of-cow, is widely used in Brazil folk medicine for the treatment of Diabetes mellitus. The purposes of present study were to determine the repercussions of diabetes on the defense system against oxidative stress in pregnant female rats and to characterize the influence of the treatment with Bauhinia forficata extract on the antioxidant system, glycemic control, hepatic glycogen, cholesterol, triglycerides, total proteins and lipids. Virgin female Wistar rats were injected with 40 mg/kg streptozotocin (STZ) before mating. Oral administration of an aqueous extract of Bauhinia forficata leaves was given to non-diabetic and diabetic pregnant rats in 3 doses: 500 mg/kg from 0 to 4(th) day of pregnancy, 600 mg/kg from 5(th) to 14(th) day and 1000 mg/kg from 15(th) to 20(th) day. All the females were killed on the day 21 of pregnancy. A maternal blood sample was collected by venous puncture and the maternal liver was removed for biochemical measurement. The diabetic pregnant rats presented hyperglycemia, hyperlipemia, bypertriglyceridemia, hypercholesterolemia, hyperuricemia, decreased determinations of reduced glutathione (GSH) and superoxide dismutase (SOD). Treatment with B. forficata extract did not interfere in the albumin, total protein and lipid, triglyceride, cholesterol and SOD determinations. Increased hepatic glycogen, decreased uric acid concentration and increased GSH activity was observed. This last fact suggests that the plant may have some action on antioxidant defense system. However, the demonstration of the active component present in B. forficata responsible for its antioxidant effect and the increase in hepatic glycogen deserve further investigation.