Scielo RSS <![CDATA[Revista Brasileira de Farmacognosia]]> vol. 24 num. 3 lang. en <![CDATA[SciELO Logo]]> <![CDATA[New drugs with antiprotozoal activity from marine algae: a review]]> The use of indigenous or remote popular knowledge to identify new drugs against diseases or infections is a well-known approach in medicine. The inhabitants of coastal regions are known to prepare algae extracts for the treatment of disorders and ailments such as wounds, fever and stomach aches, as for the prevention of arrhythmia. Recent trends in drug research from natural sources have indicated that marine algae are a promising source of novel biochemically active compounds, especially with antiprotozoal activity. Algae survive in a competitive environment and, therefore, developed defense strategies that have resulted in a significant level of chemical structural diversity in various metabolic pathways. The exploration of these organisms for pharmaceutical and medical purposes has provided important chemical candidates for the discovery of new agents against neglected tropical diseases, stimulating the use of sophisticated physical techniques. This current review describes the main substances biosynthesized by benthic marine algae with activity against Leishmania spp., Trypanosoma cruzi and Trypanosoma brucei; the causative agents of leishmaniasis, Chagas disease and African trypanosomiasis, respectively. Emphasis is given to secondary metabolites and crude extracts prepared from marine algae. <![CDATA[Pakistamide C, a new sphingolipid from <em>Abutilon pakistanicum</em>]]> The Abutilon genus from the Malvaceae family is of medicinal importance, and members of this genus are distributed in the tropical and subtropical regions of Asia and other parts of the world. Abutilon pakistanicum Jafri &amp; Ali is mainly found in Pakistan. It has been used by different systems of traditional medicines to treat different diseases. Pakistamide C, a new sphingolipid, has been isolated from the ethyl acetate soluble fraction of the methanolic extract of A. pakistanicum. Different spectroscopic techniques such as NMR (1H, 13C, COSY, NOESY, HSQC, HMBC) and Mass spectrometry (EI-MS, and FAB-MS experiments) were used to elucidate the structure of pakistamide C. <![CDATA[Synthesis and evaluation of artificial antigens for astragaloside IV]]> The objective of this study was to produce artificial antigens for astragaloside IV that could be used to prepare antibodies against astragaloside IV screened in Radix astragali (Astragalus membranaceus (Fisch) Bunge, Fabaceae) and its preparations, using an indirect ELISA. Astragaloside IV was coupled to carrier proteins, bovine serum albumin and ovalbumin using the sodium periodate method and was then evaluated using SDS-PAGE, MALDI-TOF MS and animal immunizations. The coupling ratio of astragaloside IV to bovine serum albumin ratio was determined to be thirteen, and the indirect ELISA demonstrated that three groups of mice immunized with astragaloside IV-bovine serum albumin produced anti-astragaloside IV- bovine serum albumin-specific antibody, with a minimum serum titer of 1:9600. A method for synthesizing highly immunogenic astragaloside IV artificial antigens was successfully developed thus indicating its feasibility in the establishment of a fast immunoassay for astragaloside IV content determination in Radix astragali and its products. <![CDATA[Chemical composition and efficacy in the egg-hatching inhibition of essential oil of <em>Piper aduncum</em> against <em>Haemonchus contortus</em> from sheep]]> Piper aduncum L., Piperaceae, has been used to treat mainly inflammatory diseases and has shown several biological activities such as insecticidal and larvicidal. The aim of this study was to analyze the chemical composition of essential oil of P. aduncum and its efficacy to egg-hatching inhibition of Haemonchus contortus from sheep. The essential oil was obtained from leaves and analysed by gas chromatography coupled to flame ionization detector and gas chromatography coupled to mass spectrometry. It was possible to characterize 22 different substances, among them monoterpenes (80.6%) and sesquiterpenes (13.9%). The major compound was identified as 1,8-cineole (55.8%). Eggs of the nematode were exposed to four concentrations of the essential oil. Levamisole phosphate was used as positive control. The essential oil showed to be effective in inhibiting H. contortus hatchability and the LC90 was calculated as 8.9 These results can point out the P. aduncum essential oil and its chemical components as potential alternative to control of H. contortus <![CDATA[<em>Aspidosperma subincanum</em> I. characterisation, extraction of an uleine-enriched fraction and potential health hazard due to the contaminant ellipticine]]> The bark of the Brazilian tree Aspidosperma subincanum Mart. ex A. DC., Apocynaceae, has been characterised, and its constituents concentrated to obtain an uleine-enriched extract with the aim to produce food supplements. The concentration of the contaminant alkaloid ellipticine was assessed, and its potential to elicit toxic effects on consumers evaluated. It was found that this alkaloid posited no danger. <![CDATA[Evaluation of the toxicity and molluscicidal and larvicidal activities of <em>Schinopsis brasiliensis</em> stem bark extract and its fractions]]> Dengue fever and schistosomiasis are major public health issues for which vector control using larvicide and molluscicide substances present in plants provides a promising strategy. This study evaluated the potential toxicity of the extract of hydroethanol Schinopsis brasiliensis Engl., Anacardiaceae, stem bark and its chloroform, hexane, ethyl acetate, and hydromethanol fractions against Artemia salina and Aedes Aegypti larvae and snails Biomphalaria glabrata. All of the assays were performed in triplicate and the mean mortality rates were used to determine the LC50 and LC90 values using the probit method. The hydroethanol hydromethanol extract and fraction were free of toxicity towards A. salina (LC50 &gt; 1000 µg/ml), while chloroform fraction was moderately toxic (LC50 313 µg/ml); ethyl acetate and hexane fractions displayed low toxicity, with LC50 557 and 582 µg/ml, respectively. Chloroform, hexane, and ethyl acetate fractions showed larvicidal potential towards A. aegypti (LC50 values of 345, 527 and 583 µg/ml, respectively), while chloroform and ethyl acetate fractions were highly toxic to B. glabrata (LC90 values of 68 and 73 µg/ml, respectively). Based on these findings, ethyl acetate, chloroform, and hexane fractions should be further investigated for their potential use against the vectors of dengue and schistosomiasis. <![CDATA[Biological activity of <em>Pouteria sapota</em> leaf extract on post-embryonic development of blowfly <em>Chrysomya putoria</em> (Wiedemann, 1818) (Calliphoridae)]]> Chemical insecticides have been the main way to control synanthropic flies of medical and veterinary importance; however, residuals of these products have become a factor impacting on the environment, as well as the potential toxicological that they may cause damage to humans and domestic animals. Phytochemical screening carried out with the aqueous crude extract of Pouteria sapota (Jacq.) H.E. Moore &amp; Stearn, Sapotaceae, leaves showed that coumarins, reducing sugars, flavonoids and cyanogenic glycosides were its most abundant metabolites. This study evaluated the activity of the crude aqueous extract of this plant on the post-embryonic development of Chrysomya putoria. Larvae treated with 5, 10 and 25% extract showed a decrease in the pupal period and in the newly-hatched larvae to adult period when compared to the control groups. Larvae from the 25% extract group were the lightest (45.8 mg) when compared with the control group (46.5 mg). The larval and newly-hatched larvae to adult stages were more sensitive to the leaf extract from P. sapota (5%) and the treated flies showed the low viability (47.5 and 45.5% respectively). The results demonstrated that topic treatment with P. sapota could alter C. putoria post embryonic development. <![CDATA[Study of the antimicrobial activity of metal complexes and their ligands through bioassays applied to plant extracts]]> The appearance of resistant bacteria was found to reduce the efficiency of antimicrobial therapies with the current antibiotics, thereby increasing the need for more efficient drugs for the treatment of infections. Several studies have demonstrated an increase in antimicrobial activity following the interaction of several compounds with metal ions. The present study used a methodology adapted for antimicrobial bioassays using plant extracts, in compliance with the standards of the Clinical and Laboratory Standards Institute against Gram-positive and Gram-negative bacteria. The results obtained were considered appropriate for determining MIC, MBC as for performing antimicrobial sensitivity testing with good efficiency and reproducibility. The bacteria Pseudomonas fluorescens exhibited high sensitivity to the tested compounds, being efficient to evaluate the antibacterial activity. The bioassays with the metal complexes of flavonoid quercetin and Ga(III) ions, and synthetic ligand H2bbppd and Cu(II) ions showed a greater inhibitory effect than their individual ligands, thus, the addition indicated an increase in the antimicrobial activity after the coordination. Both metal complexes exhibit good antimicrobial performances, such as low minimum inhibitory concentration (MIC ≤ 250 µg/ml), bactericidal effect and a broad activity spectrum, which qualify these compounds as suitable candidates to the next step of drugs fabrication. Nevertheless, further studies on the mechanism of growth inhibition and toxicity are needed, in order to evaluate the potential of therapeutic application. <![CDATA[Laboratory evaluation of the effects of essential oil of <em>Myrciaria floribunda</em> leaves on the development of <em>Dysdercus peruvianus</em> and <em>Oncopeltus fasciatus</em>]]> Myrciaria floribunda (H. West ex Willd.) O. Berg, Myrtaceae, is popularly known as "camboim-amarelo" and was collected at Restinga de Jurubatiba (RJ, Brazil). Leaves from this species were submitted to hydrodistillation to extract its essential oil. Monoterpenes were the main compounds found (53.9%), and 1,8-cineole was the major constituent (38.4%). Studies were carried out to evaluate the effects of this essential oil on the development of two species of agricultural pests (Oncopeltus fasciatus and Dysdercus peruvianus). The essential oil was considered effective against D. peruvianus and O. fasciatus, causing mortality in both insects. The LD50 values (µg/insect) observed were 112.44 µg/insect (O. fasciatus) and 309.64 µg/insect (D. peruvianus) after one day of treatment, and 72.18 µg/insect (O. fasciatus) and 94.42 µg/insect (D. peruvianus) after 22 days of treatment. The present study reports for the first time the bioinsecticidal activity of essential oil of Myrciaria floribunda leaves, and provides important data regarding the use of essential oils in complementary programs for pest control. <![CDATA[Anti-psoriatic activity of flavonoids from <em>Cassia tora</em> leaves using the rat ultraviolet B ray photodermatitis model]]> The plant Cassia tora L., Fabaceae, traditionally, is claimed to be useful in the treatment of psoriasis and other skin diseases. In order to evaluate this information, antipsoriatic activity of three flavonoids, namely luteolin-7-O-β-glucopyranoside (1), quercetin-3-O-β-D-glucuronide (2) and formononetin-7-O-β-D-glucoside (3), isolated from the ethanol extract of C. tora leaves were investigated using UV-B induced photodermatitis model. Further, the flavonoids present in the ethanol extract were identified using HPLC by comparing their retention time with known standard luteolin, quercetin and formononetin. In the UV induced photodermatitis model, histopathological analysis of the section revealed the absence of Munro's microabscess, elongation of rete ridges, and capillary loop dilation in ethanol extract (400 mg/kg), isolated compound 2, 3 and standard group. The ethanolic extract (400 mg/kg) and isolated compounds 1, 2 and 3 exhibited a significant (p &lt; 0.01) percentage reduction of relative epidermal thickness when compared with a positive control. In the HPLC analysis, three flavonoids were identified by comparison of the retention times of standard marker, namely luteolin, quercetin and formononetin. We concluded, using animal model, that the flavonoids from Cassia tora leaves have significant antipsoriatic activity. <![CDATA[Ulcer protective potential of standardized hesperidin, a citrus flavonoid isolated from <em>Citrus sinensis</em>]]> Free radicals play an important role in stomach ulcer formation. The present investigation validates the anti ulcer activity of hesperidin, isolated from Citrus sinensis (L.) Osbeck, Rutaceae, through the assessment of its antioxidant potential over stomach mucosal tissue by histological examination. Hesperidin was isolated from the dried peel of C. sinensis, and authenticated by TLC, IR and HPLC. The anti-ulcerogenic potential of this fruit was assessed using indomethacin and hypothermic restrain stress-induced ulceration models on rats at 150, 300 and 450 mg/kg dose orally. The parameters measured were gastric pH, volume, free and total acidity, ulcer index, and mucin, glutathione, super oxide dismutase, catalase and protein content. Hesperidin at 300 and 450 mg/kg dose showed significant (p &lt; 0.01-0.001) increase in pH, decrease in acidity and ulcer index against indomethacin and hypothermic restrain stress, along with histological evidence of cytoprotection. Glutathione, super oxide dismutase, catalase and mucin levels increased significantly at 450 mg/kg (p &lt; 0.05-0.001) after indomethacin ulceration, whereas hypothermic restrain stress only increased glutathione and mucin levels. Hesperidin prevents oxidative cell injury by significant rise of super oxide dismutase, glutathione and catalase levels in gastric mucosa. Hesperidin allowed the regeneration of ulcerated tissue, and prevented hemorrhagic injury of gastric mucosa. The potential anti-ulcer effect of hesperidin may be due to antioxidant, mucoprotective and cytoprotective activities. <![CDATA[Phytochemical screening and hypoglycemic activity of <em>Carica papaya</em> leaf in streptozotocin-induced diabetic rats]]> The extraction of plant constituents is essential to isolate biologically active compounds, aimed to understand their role on the treatment of diabetes. This study was designed to explore the preliminary phytochemical and physicochemical analysis of Carica papaya L., Caricaceae, leaf, and further evaluation of its hypoglycemic effect on diabetic rats. C. papaya leaves were extracted using chloroform, n-hexane or ethanol. For each extract a phytochemical screening was performed. The tests were conducted in triplicate and the qualitative and quantitative determination of the various metabolites was done using analytical standards proposed by Mexican Herbal Pharmacopoeia. The chloroform extract, containing steroids and quinones as major components, was chosen to study C. papaya biological effects. The chloroform extract was evaporated to dryness, and doses 0, 31, 62, 125 mg/kg were orally administered in 300 µl polyethylene glycol to diabetic rats; and 0 and 62 mg/kg to non-diabetic rats. After a 20-day treatment with the chloroform extract, the animals were sacrificed and blood was obtained for biochemical studies. The main effect observed was a decrease in serum glucose, triglycerides and transaminases in diabetic rats after the administration of C. papaya chloroform extract. These results confirm the potential beneficial action of C. papaya to treat the symptoms of diabetic patients. <![CDATA[Antinociceptive and anti-inflammatory activities of ethanolic extract of <em>Alafia barteri</em>]]> This study analyzes the antinociceptive and anti-inflammatory properties of ethanolic leaf extract of Alafia barteri Oliv., Apocynaceae, based on its medicinal use in the treatment of toothaches, inflammation and fevers. The antinociceptive effect was assessed in mice using acetic acid-induced writhing, tail clip, tail immersion and formalin assays. Anti-inflammatory activity was evaluated on carrageenan-induced paw oedema in rats, and xylene-induced ear oedema in mice. In acetic acid-induced writhing test, the extract at different doses (50, 100 and 200 mg/kg, p.o.) significantly (p &lt; 0.05) and dose-dependently reduced pain by 35.04, 56.49 and 84.25%, respectively. The extract also significantly inhibited both the early and late phases of formalin-induced nociception in mice. In the tail immersion test, the extract caused a significant inhibition of pain (34.43% inhibition, after 90 min) at a dose of 200 mg/kg, while the effect of the extract in the tail clip test was only significant at the 100 mg/kg dose. A. barteri caused a significant inhibition of paw oedema development in the carrageenan and xylene-induced oedema tests. There was no mortality recorded following treatment with the extract (5 g/kg, p.o.). The results support the traditional use of A. barteri in the treatment of various diseases associated with pain and inflammation. <![CDATA[Effects of the oral treatment with <em>Copaifera multijuga</em> oil on reproductive performance of male Wistar rats]]> Copaiba oil, extracted from Copaifera multijuga Hayne, Fabaceae, is widely used for medicinal purposes, especially to treat inflammatory processes. However, there is no report regarding its effect on reproductive performance after used in repeated doses orally. The present study evaluated the effects of the oral administration of Copaiba oil (at doses of 200, 500 or 2500 mg/kg) or water (control) for eight weeks in male Wistar rats. Treated males mated untreated females, and parameters as fertility rates, absolute and relative mass of accessory sexual organs and histology and development of the offspring were evaluated. Chemical analysis revealed the presence of 22 components accounting for 99.11% of the Copaiba oil. The main compounds identified were sesquisterpenes. The reproductive toxicology results indicate that there was no difference between the treated groups compared with the control group in any of the parameters, suggesting that the oral treatment with C. multijuga oil for eight weeks does not affect reproductive performance of male Wistar rats. <![CDATA[The effect of <em>Ginkgo biloba</em> extract treatment in the Bcl-2 expression by osteoblasts in the femoral trabecular bone of Wistar rats with glucocorticoid-induced osteoporosis]]> Evaluate the effect of the extract of Ginkgo biloba L., Ginkgoaceae (EGb) in the Bcl-2 expression by osteoblasts in the femoral trabecular bone of Wistar rats with glucocorticoid-induced osteoporosis. Rats were divided into five groups: osteoporosis; EGb1 (28 mg/kg); EGb2 (56 mg/kg); alendronate (0.2 mg/animal) and control. The treatments were conducted for 20 or 30 days. The Bcl-2 expression by osteoblasts cells was evaluated in the femoral trabecular bone. The control group was compared with the osteoporosis-induced group (Student's t-test). The other groups were analyzed by ANOVA test followed by Tukey's test (p &lt; 0.05). The percentage of Bcl-2 expression was reduced, when the control group (17.95 ± 3.45 20 days; 21.11 ± 3.43 30 days) was compared with the osteoporosis group (10.64 ± 3.30 20 days; 9.72 ± 2.84 30 days). Nevertheless, this percentage increased in the EGb2 group (18.58 ± 3.41 20 days; 16.51 ± 1.80 30 days) when compared to the osteoporosis group. The EGb increased the expression of the anti-apoptotic protein, suggesting a decrease in osteoblast apoptosis.