Chemical Characterization and Biological Activities of Jandaíra Stingless Bee Products (Melipona subnitida, Ducke, 1911): A Brief Review.

Melipona subnitida (Ducke, 1911), a species of stingless bee, popularly known as Jandaíra, has a wide distribution in the Brazilian Northeast region, being an important pollinator of the Caatinga biome. This bee produces products such as honey, geopropolis, pollen (saburá) and wax that are traditionally used for therapeutic purposes and some studies report the biological properties, as well as its chemical composition. This review aimed to select, analyze and gather data published in the literature focusing on the chemical profile and bioactivities described for M. subnitida products. Data collection was carried out through the Capes Journal Portal platform, using the following databases: Web of Science, Scopus, and PubMed. Original articles published in English and Portuguese were included, with no time limitation. The chemical composition of M. subnitida products has been investigated through chromatographic analysis, demonstrating the presence of a variety of phenolic compounds, such as flavonoids and phenylpropanoids, among other classes of secondary metabolites. These products also have several biological activities, including antioxidant, healing, antinociceptive, anti-inflammatory, antidepressant, antidyslipidemic, antiobesity, antifungal, antibacterial and prebiotic. Among the biological activities reported, the antioxidant activity was the most investigated. These data show that products derived from the stingless bee M. subnitida have promising bioactive compounds. This review provides useful information about the bioactivities and chemical profile of Melipona subnitida bee products, and a direction for future research, which should focus on understanding the mechanisms of action associated with the already elucidated pharmacological activities, as well as the bioactive properties of the main isolate's constituents identified in the chemical composition of these products.

Investigation of ethnomedicinal use of Commiphora leptophloeos (Mart.) J. B. Gillett (Burseraceae) in treatment of diarrhea.

ETHNOPHARMACOLOGICAL RELEVANCE: Commiphora leptophloeos (Mart.) J.B. Gillett, popularly known as "imburana", "imburana-de-cheiro" or "imburana-de-espinho", has been used in folk medicine for the treatment of gastrointestinal diseases, such as diarrhea. The indian tribes "Kairir-Shokó and shokó use the bark to treat diarrhea. However, there is no scientific evidence to justify the therapeutic use of this species. AIM OF THE STUDY: To investigate the ethnomedicinal use of Commiphora leptophloeos, with respect to the antimicrobial, antisecretory, antimotility and antispasmodic activities of the crude ethanolic extract obtained from its leaves (CL-EtOHL) and the mechanism underlying this action in rodents. MATERIAL AND METHODS: In the evaluation of antibacterial and antifungal activities was determined the minimum inhibitory concentration (MIC) of the extract, against different strains of bacteria and fungi. All experimental protocols were approved by the Animal Ethics Committee of the Federal University of Paraíba (045/2016). In addition, behavioral screening and acute toxicity assessment of CL-EtOHL were performed in female mice (n = 6). In the investigation of antidiarrheal activity (n = 6), frequency of defecation and number of liquid stools, were classified during 4 h, and intestinal fluid and transit were measured. In addition, the antispasmodic effect on rat ileum (n = 5) was also investigated. RESULTS: The ethanolic extract is rich in flavonoids and the main were identified as C-glycosylated flavonoids (isoorientin, orientin, and vitexin). In the evaluation of antimicrobial and antifungal activity, the extract showed moderate efficacy only against the tested strains of Candida krusei ATCC-6258, Candida parapsilosis ATCC-22019 and Candida glabrata ATCC-90030. The extract had no toxic effect until 2000 mg/kg. In castor oil-induced diarrhea, CL-EtOHL inhibited, in a dose-dependent manner, both total defecation frequency (ED50 = 380.4 ± 145.4 mg/kg) and the number of watery stools (ED50 = 151.2 ± 76.3 mg/kg). The extract showed no effect on fluid accumulation or normal intestinal transit. On the other hand, when the animals were pretreated with castor oil, the extract decreased the distance traveled by the activated charcoal (ED50 = 177.0 ± 50.3 mg/kg). In the investigation of antispasmodic effect, CL-EtOHL antagonized the contractions induced by KCl 30 mM (IC50 = 208.2 ± 25.9 µg/mL) and CCh 10-6 M (IC50 = 95. ± 22.0 µg/mL). To verify the participation of muscarinic receptors in this effect, cumulative carbachol curves were performed in the absence and presence of the extract, and a non-competitive pseudo-irreversible antagonism of these receptors was observed. CONCLUSION: The data indicate that ethanol extract obtained from the leaves of Commiphora leptophloeos has an antidiarrheal effect due to inhibition of the intestinal motility and antispasmodic effect, through the antagonism of muscarinic receptors. In addition, we suggest that flavonoids isolated from CL-EtOHL may be responsible for antidiarrheal activity of this extract. This explains its ethnomedicinal use in the treatment of diarrhea.

Chitosan Film Containing Mansoa hirsuta Fraction for Wound Healing.

Chitosan films entrapped with the Mansoa hirsuta fraction (CMHF) was developed as a new dressing for wound care. The chromatographic profile of the M. hirsuta fraction (MHF) was evaluated by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, and the results showed that MHF is rich in acid triterpenes. Physicochemical characterization of the films prepared using the solvent casting method was performed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry (TGA), differential scanning calorimetry (DCS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and mechanical properties. CMHF exhibited characteristic bands of both chitosan and MHF, revealing a physical mixture of both. CMHF presented an amorphous nature, thermostability, and dispersion of MHF in the chitosan matrix, resulting in a rough structure. Incorporation of M. hirsuta fraction into chitosan matrix favorably enhanced the mechanical performance and films thickness. The in vivo wound treatment with CMHF for seven days showed a characteristic area of advanced healing, re-epithelization, cell proliferation, and collagen formation. Furthermore, wound closure reached 100% contraction after 10 days of treatment with modulation of interleukins. The incorporation of M. hirsuta fraction into chitosan films was advantageous and showed great potential for stimulating wound repair and regeneration.

Gastroprotective effect of ethyl acetate extract from Avicennia schaueriana Stapf & Leechman and underlying mechanisms.

OBJECTIVE: Avicennia schaueriana Stapf is an endemic mangrove species widely used by traditional Brazilian communities as a folk remedy for the treatment of rheumatism, ulcers, and skin wounds. The aim of the present study was to evaluate the gastroprotective potential of the ethyl acetate extract from the leaves of A. schaueriana (As-AcOEt). METHODS: Ultra-performance liquid chromatography coupled with diode-array detection and quadrupole time-of-flight mass spectrometry (UPLC-DAD-QTOF-MS/MS) was performed to identify chemical constituents of the ethyl acetate extract from the leaves ofA. schaueriana. Total phenols, flavonoids and tannins were determined and antioxidant activity was evaluated using the DPPH and ABTS methods. The acute toxicity of As-AcOEt and gastroprotective activity on HCl/ethanol-induced gastric ulcers were assessed and mechanisms of action involving the role of nitric oxide, sulfhydryl compounds, and prostaglandins were investigated. RESULTS: Terpenes, flavonoids and tannins were detected in the extract. As-AcOEt exhibited antioxidant activity, with an EC50 of 42.2 ± 4.4 µg/mL (DPPH) and 73.2% inhibition of ABTS radicals. UPLC-DAD-QTOF-MS/MS analysis identified gallic acid, gallic acid derivative, ellagic acid, myricetin pentoside, myricetin deoxyhexose, quercetin pentoside, quercetin deoxyhexose, and other compounds. Gallic acid was isolated in this species for the first time. During the acute toxicity test, no deaths or changes occurred in the variables evaluated. In the ethanol-induced ulcer model, As-AcOEt reduced the ulcerative lesion index, with 50, 100 and 200 mg/kg achieving 83.8, 88.5 and 86.9% inhibition, respectively. MPO levels decreased and the gastric mucosa of the animals treated with the extract was preserved. Pre-treatment with N-omega-nitro-l-arginine methyl ester (L-NAME; NO blocker) or carbenoxolone (CBXN; NP-SH blocker) reversed the gastroprotective effect of As-AcOEt, but this effect was not reversed with the previous administration of indomethacin. CONCLUSION: The present findings reveal that the extract from the leaves ofA. schaueriana has gastroprotective effects, suggesting the involvement of nitric oxide and nonprotein sulfhydryl compounds, but not prostaglandin. Therefore, the use of A. schaueriana in Brazilian folk medicine for the treatment of gastric disorders has a scientific basis.

The anti-allergic activity of Cymbopogon citratus is mediated via inhibition of nuclear factor kappa B (Nf-Κb) activation.

BACKGROUND: The prevalence of allergic diseases such as asthma has significantly increased worldwide, making it a public health concern. There is an urgent need for new anti-inflammatory agents with selective pharmacology and lower toxicity. Plant extracts have been used for centuries in traditional medicine to alleviate inflammatory diseases. In this work, we evaluated the anti-allergic activity of Cymbopogon citratus (Cy), a medicinal herb used by folk medicine to treat asthma. METHODS: We used a murine model of respiratory allergy to the mite Blomia tropicalis (Bt) and evaluated certain parameters known to be altered in this model. A/J mice were sensitized (100 µg/animal s.c.) and challenged (10 µg/animal i.n.) with Bt mite extract and treated with 60, 120 or 180 mg/kg of Cy standardized hexane extract. The parameters evaluated included: cellular infiltrate in bronchoalveolar lavage (BAL); eosinophil peroxidase activity (EPO); histopathological examination of the lung; serum levels of specific IgE, IgG1 and IgG2a; Th2 cytokine concentrations in BAL and expression of NF-κB. RESULTS: Our results showed that oral administration of a Cy hexane extract (especially 180 mg/Kg) reduced the numbers of leukocytes/eosinophils in BAL; the eosinophil peroxidase activity in BAL; the infiltration of leukocytes in lung tissue; the production of mucus in the respiratory tract; the level of IL-4 in BAL and the nuclear expression of NF-κB. CONCLUSIONS: The results presented demonstrate the potential of the Cy hexane extract to modulate allergic asthma; this extract may be an alternative future approach to treat this pathology.