Tania Maria Sarmento Silva

Anti-allergic effect of bee pollen phenolic extract and myricetin in ovalbumin-sensitized mice

ETHNOPHARMACOLOGICAL RELEVANCE The bee pollen is used in folk medicine to alleviate allergic reactions. The bee pollen phenolic extract (BPPE) consists in phenolic compounds (flavonoids) from plants picked by Apis mellifera bee. AIM OF THIS STUDY Here we evaluated the anti-allergic property of the BPPE and the flavonoid myricetin (MYR) in murine model of ovalbumin (OVA)-induced allergy. MATERIALS AND METHODS The study focused on the BPPE or myricetin treatment of OVA-sensitized BALB/c mice and their effects on the IgE and IgG1 production, pulmonary cell migration, eosinophil peroxidase (EPO) activity and anaphylactic shock reaction. RESULTS The BPPE treatment (200mg/kg) showed inhibition of the paw edema, IgE and IgG(1) OVA-specific production, leukocyte migration to the bronchoalveolar lavage (BAL) and EPO activity in lungs. In addition, BPPE treatment showed partial protection on the anaphylactic shock reaction induced by OVA. Treatment with myricetin (5 mg/kg) also inhibited pulmonary cell migration and IgE and IgG(1) OVA-specific production. CONCLUSIONS These results support the hypothesis the myricetin is one of the flavonoids of BPPE responsible for the anti-allergic effect and a potential tool to treat allergies.

Antibacterial activity, chemical composition, and cytotoxicity of leaf's essential oil from Brazilian pepper tree (Schinus terebinthifolius, Raddi)

The antibacterial potential of leafs essential oil (EO) from Brazilian pepper tree (Schinus terebinthifolius Raddi) against staphylococcal isolates from dogs with otitis externa was evaluated. The minimum inhibitory concentration of EO ranged from 78.1 to 1,250 fg/mL. The oil was analyzed by GC and GC/MS and cytotoxicity tests were carried out with laboratory animals.

Palynological Origin, Phenolic Content, and Antioxidant Properties of Honeybee-Collected Pollen from Bahia, Brazil

The aim of this study was to determine the palynological origin, phenolic and flavonoid content, and antioxidant properties of twenty-five samples of bee pollen harvested during a nine-month period (February–November) from the Canavieiras municipality (northeastern Brazil). Of the 25 samples analyzed, only two (February 01 and 02) were heterofloral. The predominant pollens in the samples analyzed during that month were: Cecropia, Eucalyptus, Elaeis, Mimosa pudica, Eupatorium, and Scoparia. Ethyl acetate fractions were analyzed by HPLC-DAD. The flavonoids isoquercetin, myricetin, tricetin, quercetin, luteolin, selagin, kaempferol, and isorhamnetin were detected. The flavonoid present in all 22 samples was isolated and identified as isorhamnetin 3-O-β-neohesperidoside. The total phenolic contents determined using the Folin-Ciocalteu reagent ranged from 41.5 to 213.2 mg GAE/g. Antioxidant activities based on the 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2-azinobis 3-ethylbenzothiozoline-6-sulfonic acid (ABTS), and Fe2+ ion chelating activity assays were observed for all extracts, and correlated with the total phenolic content.

Brine shrimp bioassay of some species of Solanum from Northestern Brazil

The methanolic extracts of 13 Specieis of the genus Solanum (Solanaceae) have been tested for bioactivity in Artemia salina. The extracts investigated were prepared from various parts (aerial parts, roots and fruits) of S. asperum, S. capsicoides, S. palinacantum, S. paludosum, S. paniculatum, S. paraibanum, S. sisymbriifolium, S. crinitum, S. diamantinense, S. megalonyx, S. torvum, S. asterophorum and S. stipulaceum. The lethal concentrations were determined for the extracts and among thirteen plants tested, four appear to be inactive. The extracts of the fruits of S. asperum (LC50 = 420.5 µg/mL) and S. paludosum (LC50 = 548.0 µg/mL), aerial parts of S. diamantinense (LC50 = 481.0 µg/mL) and S. sisymbrifolium (LC50 = 382.7 µg/mL), and the roots of S. asperum (LC50 = 593.4 µg/mL) and S. stipulaceum (LC50 = 823.1 µg/mL), all of which previously showed molluscicidal activity against Biomphalaria glabrata were also found to be active in the present study with brine shrimp.

Quantification, Antioxidant and Antimicrobial Activity of Phenolics Isolated from Different Extracts of Capsicum frutescens (Pimenta Malagueta)

This paper presents the quantification, antioxidant and antimicrobial activity of capsaicin, dihydrocapsaicin and the flavonoid chrysoeriol isolated from different extracts (hexane and acetonitrile extracts from whole fruit, peel and seed) of Capsicum frutescens (pimenta malagueta). The acetonitrile extract of the seeds, peel and whole fruits contained capsaicin as a major component, followed in abundance by dihydrocapsaicin and chrysoeriol. The antimicrobial activity of the isolated compounds against seven microorganisms showed chrysoeriol was the most active compound. In the antioxidant test, the acetonitrile extract from the whole fruit showed the highest activity. The antioxidant activity of pimenta malagueta may be correlated with its phenolic content, principally with the most active compound, capsaicin.

Molluscicidal activity of 2-hydroxy-[1,4]naphthoquinone and derivatives

The toxic profile of lawsone (2-hydroxy-[1,4]naphthoquinone) and a series of [1,4]naphthoquinone derivatives was evaluated against the brine shrimp Artemia salina and against the mollusk Biomphalaria glabrata, the main transmitting vector of schistosomiasis in Brazil. Of the seventeen compounds tested nine fell below the threshold of 100 microg/mL set for potential molluscicidal activity by the World Health Organization. As a general rule derivatives with non-polar substituents presented the highest molluscicidal activities. These substances showed significant toxicity in A. salina lethality bioassay.

Composition and Molluscicidal Properties of Essential Oils from Leaves of Xylopia langsdorffiana A. St. Hil. et Tul. (Annonaceae)

Abstract The volatile fraction of Xylopia langsdorffiana leaves was analyzed by GC and GC/M S and tested for molluscicidal activity. With this methodology 19 different components were identified in the oil. Among them, germacrene D (22.9%), trans-β-guaiene (22.6%), β-caryophyllene (15.7%), and α-pinene (7.3%) were found to be the major constituents. The oil showed significant molluscicidal activity against Biomphalaria glabrata, with an LC90 value of 5.6 μg/mL, which falls below the threshold of 100 μg/mL, set for potential molluscicidal activity by the World Health Organization.

Characterisation of a new exopolysaccharide obtained from of fermented kefir grains in soymilk

Microbial exopolysaccharides (EPSs) have been widely studied in recent decades due to similarity to gums used in the food industry. Exopolysaccharides can be used in food processing as a thickener and/or stabiliser. This study aimed to investigate the physicochemical properties, thermal behaviour and structural composition of the lyophilised EPS obtained from the fermentation of kefir grains in soymilk. The EPS in concentration 18 mg/mL exhibited water activity of 0.204 and pH=6.20 at 25°C, reducing sugars content of 22.10% (v/v) and protein content of 2% (v/v). The thermogravimetric curve obtained was similar to those reported in the literature for other EPSs. The degradation temperature was 351.84°C and showed that the EPS in this study had a high thermal stability. Characteristic polysaccharide bands were observed in the infrared spectrum. The analysis by liquid chromatography coupled to electrospray ionisation mass spectrometry (LC-ESI-MS) showed that the EPS is only composed of glucose.

Composition and Antioxidant Activity of Geopropolis Collected by Melipona subnitida (Jandaíra) Bees

An investigation of the geopropolis collected by Melipona subnitida (jandaíra) stingless bee led to the isolation and characterization of two phenylpropanoids, 6-O-p-coumaroyl-D-galactopyranose (1) and 6-O-cinnamoyl-1-O-p-coumaroyl-β-D-glucopyranose (2), and seven flavonoids, 7-O-methyl-naringenin (3), 7-O-methyl aromadendrin (4), 7,4′-di-O-methyl aromadendrin (5), 4′-O-methyl kaempferol (6), 3-O-methyl quercetin (7), 5-O-methyl aromadendrin (8), and 5-O-methyl kaempferol (9). The structure of the new phenylpropanoid (1) was established from IR, LC-ESI-MS, and NMR spectral data, including 2D NMR experiments. The extract and fractions demonstrated significant antioxidant activity in DPPH, ABTS, and β-carotene/linoleic acid tests.

Studies on the alkaloids of Solanum of northeastern Brazil

In our continued studies on the genus Solanum for detecting a good source of soladodine, the steroid alkaloid potentially important for the manufacture of steroid hormones, as well as other compounds of potential therapeutic value, we investigated the fruits of Solanum crinitum, S. rhytidoandrum, and S. jabrense belonging to the subgenus Leptostemonum and S. stipulaceum, belonging to the subgenus Brevantherum, allof which are native of the northeastern region of Brazil and yielded solasodine in moderate to high yield.