Ícaro Gusmão Pinto Vieira

Quantification of bioactive compounds in pulps and by-products of tropical fruits from Brazil

This study aimed to quantify the levels of resveratrol, coumarin, and other bioactives in pulps and by-products of twelve tropical fruits from Brazil obtained during pulp production process. Pineapple, acerola, monbin, cashew apple, guava, soursop, papaya, mango, passion fruit, surinam cherry, sapodilla, and tamarind pulps were evaluated as well as their by-products (peel, pulps leftovers, and seed). Total phenolic, anthocyanins, yellow flavonoids, β-carotene and lycopene levels were also determined. Resveratrol was identified in guava and surinam cherry by-products and coumarin in passion fruit, guava and surinam cherry by-products and mango pulp. These fruit pulp and by-products could be considered a new natural source of both compounds. Overall, fruit by-products presented higher (P<0.05) bioactive content than their respective fruit pulps. This study provides novel information about tropical fruits and their by-products bioactive composition, which is essential for the understanding of their nutraceutical potential and future application in the food industry.

Variation of Ursolic Acid Content in Eight Ocimum Species from Northeastern Brazil

Ursolic acid is a very important compound due to its biological potential as an anti-inflammatory, trypanocidal, antirheumatic, antiviral, antioxidant and antitumoral agent. This study presents the HPLC analysis of ursolic acid (UA) content in eight different Ocimum species: O. americanum L., O. basilicum L, O. basilicum var purpurascens Benth, O. basilicum var. minimum L, O. gratissimum L, O. micranthum Willd, O. selloi Benth. and O. tenuiflorum L. grown in Northeastern Brazil. In these Ocimum species, UA was detected in different yields, with O. tenuiflorum showing the highest content (2.02%). This yield is very significant when compared with other sources of UA.

Determination of synthetic food dyes in commercial soft drinks by TLC and ion-pair HPLC.

Synthetic food colourings were analyzed on commercial carbonated orange and grape soft drinks produced in Ceará State, Brazil. Tartrazine (E102), Amaranth (E123), Sunset Yellow (E110) and Brilliant Blue (E133) were extracted from soft drinks using C18 SPE and identified by thin layer chromatography (TLC), this method was used to confirm the composition of food colouring in soft drinks stated on label. The concentration of food colouring in soft drink was determined by ion-pair high performance liquid chromatography with photodiode array detection. The results obtained with the samples confirm that the identification and quantification methods are recommended for quality control of the synthetic colours in soft drinks, as well as to determine whether the levels and lables complies with the recommendations of food dyes legislation.

Analytical MethodsDetermination of synthetic food dyes in commercial soft drinks by TLC and ion-pair HPLC

Synthetic food colourings were analyzed on commercial carbonated orange and grape soft drinks produced in Ceará State, Brazil. Tartrazine (E102), Amaranth (E123), Sunset Yellow (E110) and Brilliant Blue (E133) were extracted from soft drinks using C18 SPE and identified by thin layer chromatography (TLC), this method was used to confirm the composition of food colouring in soft drinks stated on label. The concentration of food colouring in soft drink was determined by ion-pair high performance liquid chromatography with photodiode array detection. The results obtained with the samples confirm that the identification and quantification methods are recommended for quality control of the synthetic colours in soft drinks, as well as to determine whether the levels and lables complies with the recommendations of food dyes legislation.

Antioxidant, larvicidal and antiacetylcholinesterase activities of cashew nut shell liquid constituents

Anacardic acid, cardanol and cardol, the main constituents of natural cashew nut shell liquid (CNSL), were obtained by solvent extraction and assayed for antioxidant, larvicidal and antiacetylcholinesterase activity. Their relative percent composition was obtained by HPLC analysis. Antioxidant activity was assessed using the DPPH and ABTS(+) tests, which showed cardanol as the most active, followed by cardol and anacardic acid. The three CNSL components demonstrated good larvicidal activity against Aedes aegypti (LC(50)=12.40 for anacardic acid, 10.22 for cardol and 14.45 for cardanol) and exhibited inhibition zones for acetylcholinesterase enzymes in the TLC test similar to carbachol, which was used as standard. Based on the results, these multipotent compounds represent promising agents in the control of Ae. aegypti, the main dengue vector in Brazil.

Different susceptibilities of Leishmania spp. promastigotes to the Annona muricata acetogenins annonacinone and corossolone, and the Platymiscium floribundum coumarin scoparone

Leishmaniasis is a zoonotic disease that can manifest itself in visceral and cutaneous form. The aim of this study was to search for new leishmanicidal compounds. Preliminarily, Artemia salina assay was applied to compounds from two plants found in Northeastern Brazil, Platymiscium floribundum and Annona muricata. Then these compounds were tested against three Leishmania species (Leishmania donovani, Leishmania mexicana and Leishmania major). A screening assay using luciferase-expressing promastigote form were used to measure the viability of promastigote One coumarin, scoparone, isolated from P. floribundum and two acetogenins, annonacinone and corossolone isolated from A. muricata showed leishmanicidal activity in all species tested. Nevertheless, Leishmania species indicated different susceptibilities in relation to the tested compounds: L. mexicana was more sensitive to scoparone followed by L. major and L. donovani. The three species presented similar inhibition to corossolone and annonacinone. Acetogenin annonacinone (EC(50)=6.72-8.00 μg/mL) indicated high leishmanicidal activity; corossolone (EC(50)=16.14-18.73 μg/mL) and scoparone (EC(50)=9.11-27.51 μg/mL) moderate activity. A. saline larvae were less sensitive to the coumarin scoparone and acetogenin corossolone was the most toxic. In conclusion, the leishmanicidal activity demonstrated by the coumarin and acetogenins indicate these compounds for further studies aiming the development of new leishmanicidal agents.

Chemical composition, antioxidant and antibacterial activities of two Spondias species from Northeastern Brazil

Context: The leaves of Spondias tuberosa Arr. Cam. (Anacardiaceae) and Spondias mombin L. have been traditionally used for medicinal purposes. Some studies reveal their antibacterial, antimicrobial, and antiviral properties. Objective: Determine the chemical composition, antioxidant, and antimicrobial activities of Spondias species to justify its ethnopharmacological use. Materials and methods: Spondias species extracts were prepared with methanol:water 80:20 and analyzed by silica gel column chromatography and reversed phase liquid chromatography (HPLC). The antioxidant activity was evaluated by scavenging the radicals 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS•+) and measuring antimicrobial activity (agar well diffusion method, minimum inhibitory concentration and minimum bactericidal concentrations). Results: The HPLC analysis of Spondias extracts demonstrated the occurrence of high yield of flavonoids. Found in S. mombin were quercetin (2.36 ± 0.01 mg/g) and ellagic acid (41.56 ± 0.01 mg/g) and in S. tuberosa species rutin (53.38 ± 1.71 mg/g), quercetin (24.46 ± 0.87 mg/g), and ellagic acid (169.76 ± 0.17 mg/g). The antibacterial activity of the extracts against the various bacteria strains varied from 8.8 to 20.1 mm. MIC values from 62.5 to 125 µg/mL were satisfactory when compared with other plant products. Medium DPPH scavenging activity IC50 for Spondias extracts varied from 0.042 to 0.558 mg/mL and for ABTS from 0.089 to 0.465 mg/mL. DPPH scavenging activity for constituent ellagic acid IC50 = 0.042 mg/mL and for quercetin IC50 = 0.081 mg/mL. Discussion and conclusion: The chemical study of Spondias leaf extracts showed the occurrence of quercetin, rutin and ellagic acid, substances with relevant antioxidant and antimicrobial activities.

Larvicidal Activity of Tagetes erecta Against Aedes aegypti

Abstract The aim of this study was to evaluate the activity of essential oil from Tagetes erecta against 3rd instars of Aedes aegypti and to determine the amounts of larvicidal thiophenes in all plant tissues. The oil obtained by steam distillation and analyzed by gas chromatography/mass spectrometry showed 14 compounds. The main compounds were piperitone (45.72%), d-limonene (9.67%), and piperitenone (5.89%). The essential oil was active against larvae of Ae. aegypti, with LC50 of 79.78 µg/ml and LC90 of 100.84 µg/ml. The larvicidal thiophene contents were higher in the roots and flowers as demonstrated by high-performance liquid chromatography analysis. Thus, T. erecta constitutes a good source of varied compounds showing larvicidal activity against Ae. aegypti.

Antiherpetic activity of an Agaricus brasiliensis polysaccharide, its sulfated derivative and fractions.

Agaricus brasiliensis is an edible mushroom, traditionally used for the treatment of several diseases. In this paper, a polysaccharide (PLS) from A. brasiliensis, its carboxymethylated (CPLS) and sulfated (SPLS) derivatives, as well as, fractions (F1-F3) obtained from the PLS were investigated for their effect in the replication of herpes simplex virus and bovine herpes virus in HEp-2 cell cultures. The PLS, SPLS and F3 inhibited both virus strains similarly, in a dose-dependent curve. F1, F2 and CPLS did not show significant effect even at higher concentrations. All the compounds showed neither virucidal or viral adsorption inhibition activities nor effect when cells were treated prior to infection. Our study demonstrated that the extracts of A. brasiliensis, can be promising for future antiviral drug design and its biotechnological production is economically feasible.

Gastroprotective effect of Byrsonima sericea DC leaf extract against ethanol-induced gastric injury and its possible mechanisms of action

Byrsonima sericea leaves are extensively used in folk medicine in Brazil against gastric disorders. This study investigated the chemical constituents of B. sericea leaf ethanolic extract (BSLE) and its potential gastroprotective activity, with its possible mechanism of the action using ethanol to induce gastric mucosal damage in mice. The phytochemical analysis was carried out to identify the active constituents present in the extract, and the HPLC analysis was performed for the identification of flavonoids. BSLE at oral doses of 125, 250 and 500 mg/kg markedly attenuated the ethanol-evoked gastric lesions by 53.2, 84.9 and 87.6 %, respectively. The BSLE (250 mg/kg) prevented the depletion of gastric mucus and gastric mucosal nonproteic-sulfhydryl groups, SOD and CAT, as well as the increase in the MDA content promoted by absolute ethanol. Moreover, the effect of BSLE against ethanol damage was found to be significantly reduced in mice pretreated with Capsazepine (i.p.), L-NAME (i.p.) or glibenclamide (i.p.), the respective blockers/inhibitors of TRPV1, NO synthase and K+ATP channel. The phytochemical investigation on BSLE revealed the presence of flavonoids rutin, isoquercitrin, kaempferol 3-O-rutinoside and quercetin, which are compounds well known for their antioxidant and gastroprotective properties. These results suggest that BSLE affords gastroprotection through multiple mechanisms, which may be helpful in the treatment of pathologies associated with gastric dysfunctions.