RESUMO
Propolis is used by corbiculated bees to protect the bee hive; it is mostly used to seal cracks, to reduce or prevent microbial growth and to embalm invaders. Different factors have been reported to influence the chemical composition of propolis, including bee species and the flora surrounding the hive. Nevertheless, the majority of the studies are focused on propolis produced by Apis mellifera, while studies on the chemical composition of propolis produced by stingless bees are still limited. In this investigation, the chemical composition of 27 propolis samples collected in the Yucatan Peninsula from A. mellifera beehives, together with 18 propolis samples from six different species of stingless bees, were analyzed by GC-MS. Results showed that lupeol acetate and ß-amyrin were the characteristic triterpenes in propolis samples from A. mellifera, while grandiflorenic acid and its methyl ester were the main metabolites present in samples from stingless bees. Multivariate analyses were used to explore the relationship between bee species and botanical sources on the chemical composition of the propolis samples. Differences in body size and, therefore, foraging abilities, as well as preferences for specific botanical sources among bee species, could explain the observed variation in propolis chemical composition. This is the first report on the composition of propolis samples from the stingless bees Trigona nigra, Scaptotrigona pectoralis, Nannotrigona perilampoides, Plebeia frontalis and Partamona bilineata.
Assuntos
Ascomicetos , Própole , Animais , Própole/química , México , Cromatografia Gasosa-Espectrometria de Massas , Análise MultivariadaRESUMO
BACKGROUND: Drugs for the treatment of liver diseases are scarce and not effective enough. Some species of the genus Cirsium possess hepatoprotective activity. There are no studies on the hepatoprotective effects of nonpolar extracts from inflorescences of thistles Cirsium vulgare and Cirsium ehrenbergii, and there are few reports on their chemical composition. OBJECTIVE: The aim is to obtain the hexane extract from inflorescences of both thistles and to identify preliminarily their main chemical component, and to evaluate the hepatoprotective properties of the extracts. MATERIALS AND METHODS: Hexane extracts were obtained using a Soxhlet apparatus. The chemical composition was analyzed using infrared spectra and gas chromatography-mass spectrometry. Two doses (250 and 500 mg/kg, p.o.) of both extracts were administered to assess their hepatoprotective effect on acute carbon tetrachloride (TC)-induced liver damage in rats using biochemical markers of necrosis, cholestasis, functionality, oxidative stress, and histological analysis. RESULTS: Extracts were shown to have a very similar chemical profile. Their major constituent seems to be lupeol acetate. The two doses of both extracts demonstrated comparable hepatoprotective properties because they significantly diminished all the liver injury indicators (P < 0.05) and were corroborated using histopathology. CONCLUSION: This is the first study on the hepatoprotective effects of nonpolar extracts from inflorescences of thistles C. vulgare and C. ehrenbergii. Hexane extracts administration totally prevented the acute TC-induced liver damage. The preliminary chemical analysis strongly suggests the lupeol acetate as their major constituent. Lupeol and its derivatives have been previously reported as antiinflammatory and hepatoprotective agents. SUMMARY: Hexane extracts of both thistles kept normal liver functionality and glycogen store in carbon tetrachloride-induced acute liver damageHexane extracts of both thistles showed anti-necrotic and anti-cholestatic effects, also diminished the lipid peroxidation and nitric oxide levels on the carbon tetrachloride-induced acute liver damageThe two doses of hexane extracts administered (250 and 500 mg/kg) prevented the liver injury in a very similar extentBoth nonpolar extracts are chemically very similar and their main compound seems to be lupeol acetate. Abbreviations used: TC: Carbon tetrachloride; FT-IR: Fourier transform Infrared spectroscopy; GC-MS: Gas chromatography - Mass spectrometry; V: Vehicle; E: Extract; Ecv: Extract of Cirsium vulgare; Ece: Extract of Cirsium ehrenbergii; AP: Alkaline phosphatase; GGTP: γ-Glutamyl transpeptidase; ALT: Alanine aminotransferase; DB: Direct bilirubin; TB: Total bilirubin; LP: Lipid peroxidation; MDA: Malondialdehyde; NO: Nitric oxide; TNF-α: Tumor necrosis factor-α.
RESUMO
Hexane, ethanol and aqueous extracts and fractions from leaves of Pouteria torta (Mart.) Radlk (Sapotaceae), a perennial tree, widespread in the Brazilian Cerrado, were tested for cytotoxicity with the Artemia salina toxicity model. Only the aqueous crude extract and the MeCN:CHCl3 fraction of the ethanol extract presented toxicity (0.28 mg/mL and 0.27mg/mL, respectively). Lupeol acetate was isolated from the hexane extract. It is the first report of lupeol acetate from the genus Pouteria.
RESUMO
For the first time, a yolk immunoglobulins-based immunenzymatic assay (capture IgY-ELISA) was carried out to detect Lupeol acetate (LAc) from Vernonia scorpioides Lam. Pers (Asteraceae). Antibodies (IgY) against lupeol acetate (anti-LAc antibodies) were raised in White Leghorn hens immunized with LAc conjugated to the bovine serum albumin (LAc-BSA). The anti-LAc antibodies were recovered by cleanup columns containing LAc-BSA coupled to sepharose. The capture IgY-ELISA efficacy was of 97% when the predictive indices of sensitivity and specificity were 99.0% and 95%, respectively. The lowest and highest detection limits were of 0.02µg g-1 and 10µg.g-1 of plant extract, respectively. The strength of this method was attested by its high reproducibility (between 94.75% and 96.81%), and a low internal variation (4.22 ± 1.03%), under the described conditions.
O presente experimento descreve, pela primeira vez, a elaboração de um ensaio imunoenzimático (ELISA de captura) com anticorpos IgY para a detecção e quantificação de acetato de lupeol (LAc) em Vernonia scorpioides Lam. Pers (Asteraceae). Anticorpos anti-LAc, obtidos partir do soro das aves e gemas de seus ovos, após imunização com o conjugado acetato de lupeol-cBSA, foram concentrados em coluna contendo LAc-BSA acoplado a sepharose. A eficácia da metodologia de detecção imunológica foi de 97%, com índices de sensibilidade e especificidade de 99% e 95%, respectivamente com limites de detecção do ensaio entre 0,02µg.g-1 (inferior) e 10 µg.g-1 (superior). A robustez do método foi atestada pela sua elevada reprodutibilidade (entre 94,75% e 96,81%), e pelo baixo coeficiente de variação interna (4,22 ± 1,03%) nas condições de execução descritas.
RESUMO
For the first time, a yolk immunoglobulins-based immunenzymatic assay (capture IgY-ELISA) was carried out to detect Lupeol acetate (LAc) from Vernonia scorpioides Lam. Pers (Asteraceae). Antibodies (IgY) against lupeol acetate (anti-LAc antibodies) were raised in White Leghorn hens immunized with LAc conjugated to the bovine serum albumin (LAc-BSA). The anti-LAc antibodies were recovered by cleanup columns containing LAc-BSA coupled to sepharose. The capture IgY-ELISA efficacy was of 97% when the predictive indices of sensitivity and specificity were 99.0% and 95%, respectively. The lowest and highest detection limits were of 0.02µg g-1 and 10µg.g-1 of plant extract, respectively. The strength of this method was attested by its high reproducibility (between 94.75% and 96.81%), and a low internal variation (4.22 ± 1.03%), under the described conditions.
O presente experimento descreve, pela primeira vez, a elaboração de um ensaio imunoenzimático (ELISA de captura) com anticorpos IgY para a detecção e quantificação de acetato de lupeol (LAc) em Vernonia scorpioides Lam. Pers (Asteraceae). Anticorpos anti-LAc, obtidos partir do soro das aves e gemas de seus ovos, após imunização com o conjugado acetato de lupeol-cBSA, foram concentrados em coluna contendo LAc-BSA acoplado a sepharose. A eficácia da metodologia de detecção imunológica foi de 97%, com índices de sensibilidade e especificidade de 99% e 95%, respectivamente com limites de detecção do ensaio entre 0,02µg.g-1 (inferior) e 10 µg.g-1 (superior). A robustez do método foi atestada pela sua elevada reprodutibilidade (entre 94,75% e 96,81%), e pelo baixo coeficiente de variação interna (4,22 ± 1,03%) nas condições de execução descritas.