Ritiel Corrêa da Cruz

Antimycobacterial activity of the fractions and compounds from Scutia buxifolia

The antimycobacterial activity of Scutia buxifolia Reissek, Rhamnaceae, leaves extracts and fractions were evaluated for the first time. Four compounds were identified, flavonoids (quercetin and quercitrin) and phenolic acids (gallic and caffeic acids) and quantified by HPLC-DAD. Promising anti-Mycobacterium smegmatis activity was observed with ethyl acetate extract (MIC 312.50 µg/mL) and their fractions (MIC values ranging from 78.12 to above 312.50 µg/mL). The fractions III and VI of S. buxifolia leaves showed a high level of activity against M. smegmatis (MIC 78.12 and 156.25 µg/mL, respectively), M. tuberculosis (MIC 156.25 µg/mL) and M. avium (MIC 312.50 µg/mL), whereas to the other fractions the values varied from 312.50 to 1250.00 µg/mL against these strains. The better MIC result was associated with two fractions that contain bigger amounts of quercetin, quercitrin, gallic and caffeic acids. The results provided evidence that the studied plants fractions might be potential sources of new antimicrobial drug.

In vitro antimycobacterial activity and HPLC–DAD screening of phenolics from Ficus benjamina L. and Ficus luschnathiana (Miq.) Miq. leaves

The total phenolic content (Folin-Ciocalteu) of the leaves of Ficus benjamina and Ficus luschnathiana was evaluated and screened by HPLC–DAD. Ficus luschnathiana crude extract (CE) presented phenolic content higher than that of F. benjamina (149.92 ± 3.65 versus 122.63 ± 2.79 mg of GAE). Kaempferol (1.63 ± 0.16 mg g−1 dry weight of CE) and chlorogenic acid (17.77 ± 0.57 mg g−1 of butanolic fraction) were identified and quantified in F. benjamina, whereas rutin (1.39 ± 0.20 mg g−1), caffeic (1.14 ± 0.13 mg g−1) and chlorogenic (3.73 ± 0.29 mg g−1) acids were quantified in the CE of F. luschnathiana. Additionaly, rutin (15.55 ± 1.92 mg g−1) and quercetin (3.53 ± 0.12 mg g−1) were quantified in ethyl acetate and butanolic fractions, respectively. Antimycobacterial activity of CEs and fractions was evaluated against Mycobacterium smegmatis by broth microdilution method. Ethyl acetate fraction from F. benjamina and n-butanol fraction from F. luschnathiana displayed the highest inhibitory activity (MIC = 312.50 µg mL−1 and 156.25 µg mL−1, respectively). Further studies are required to identify the compounds directly related to antimycobacterial activity.

Analysis of rutin in the extract and gel of Viola tricolor.

Heartsease, also known as wild pansy (Viola tricolor L.), contains considerable amounts of polyphenols: 109.32 ± 1.29 mg of Gallic acid equivalent/g of extract. This study investigates their phytoconstituents and antioxidant capacity and validates a method for the quantification of rutin in the crude extract of the flowers of V. tricolor and in the extract incorporated in gel. Much better antioxidant capacity was found for the extract [inhibition concentration (IC50) of 16.00 ± 0.78 µg/mL] than the standard ascorbic acid (IC50 of 16.57 ± 0.95 µg/mL); these excellent results may be attributable to the amounts of polyphenols, flavonoids and condensed tannins. The high-performance liquid chromatography method for the quantification of rutin in the extract and gel was linear, sensitive, precise, specific, accurate and robust. This validated method can be used to control the quality of the extract and the gel.

Influence of Trypanosoma evansi in adenine nucleotides and nucleoside concentration in serum and cerebral cortex of infected rats

This study aimed to evaluate the adenine nucleotides and nucleoside concentration in serum and cerebral cortex of rats infected with Trypanosma evansi. Each rat was intraperitoneally infected with 1 × 10(6) trypomastigotes suspended in cryopreserved blood (Group A; n = 18). Twelve animals were used as controls (Group B). The infected animals were monitored daily by blood smears. At days 4 and 20 post-infection (PI) it was collected serum and cerebral cortex to measure the levels of ATP, ADP, AMP and adenosine by high performance liquid chromatography (HPLC). In serum there was a significant (P < 0.05) increase in the ATP, AMP and adenosine concentrations at days 4 and 20 PI in infected rats when compared to not-infected. Furthermore, in the cerebral cortex it was observed a significant (P < 0.05) increase in the concentrations of ATP, AMP and decreased adenosine levels at day 4 PI. At day 20 PI it was only observed an increase in the AMP and adenosine concentrations in cerebral cortex of infected rats when compared to not-infected. It was not observed any difference in ADP concentration in serum and brain at days 4 and 20 PI. No change was observed histologically in the cerebral cortex of infected animals. The results allow us to conclude that infection with T. evansi in rats causes an increase in the concentrations of ATP, AMP and adenosine in serum and cerebral cortex the time periods evaluated. These alterations occurred as a result of T. evansi infection which involves neurotransmission, neuromodulation and immune response impairment confirm the importance of the purinergic system in this pathology.

Nicotine alters the ectonucleotidases activities in lymphocytes: In vitro and in vivo studies

The aim of the present study was to investigate the effects in vivo and in vitro of nicotine, an important immunosuppressive agent, on NTPDase and ADA activities in lymphocytes of adult rats. The following nicotine doses in vivo study were evaluated: 0.0, 0.25 and 1.0mg/kg/day injected subcutaneously in rats for 10days. The activity of the enzymes were significantly decreased with nicotine 0.25 and 1mg/kg which inhibited ATP (22%, 54%), ADP (44%, 30%) hydrolysis and adenosine (43%, 34%) deamination, respectively. The expression of the protein NTPDase in rat lymphocytes was decreased to nicotine 1mg/kg and the lymphocytes count was decreased in both nicotine doses studied. The purine levels measured in serum of the rats treated with nicotine 0.25mg/kg significantly increased to ATP (39%), ADP (39%) and adenosine (303%). The nicotine exposure marker was determinate by level of cotinine level which significantly increased in rats treated with nicotine 0.25 (39%) and 1mg/kg (131%) when compared to rats that received only saline. The second set of study was in vitro assay which the ATP-ADP-adenosine hydrolysis were decreased by nicotine concentrations 1mM (0% - 0% - 16%, respectively), 5mM (42% - 32% - 74%, respectively), 10mM (80% - 27% - 80%, respectively) and 50mM (96% - 49% - 98%, respectively) when compared with the control group. We suggest that alterations in the activities of these enzymes may contribute to the understanding of the mechanisms involved in the suppression of immune response caused by nicotine.

In vitro antimicrobial and antimycobacterial activity and HPLC–DAD screening of phenolics from Chenopodium ambrosioides L.

The main objective of this study was to demonstrate the antimicrobial potential of the crude extract and fractions of Chenopodium ambrosioides L., popularly known as Santa-Maria herb, against microorganisms of clinical interest by the microdilution technique, and also to show the chromatographic profile of the phenolic compounds in the species. The Phytochemical screening revealed the presence of cardiotonic, anthraquinone, alkaloids, tannins and flavonoids. The analysis by HPLC–DAD revealed the presence of rutin in the crude extract (12.5 ± 0.20 mg/g), ethyl acetate (16.5 ± 0.37 mg/g) and n-butanol (8.85 ± 0.11 mg/g), whereas quercetin and chrysin were quantified in chloroform fraction (1.95 ± 0.04 and 1.04 ± 0.01 mg/g), respectively. The most promising results were obtained with the ethyl acetate fraction, which inhibited a greater number of microorganisms and presented the lowest values of MIC against Staphylococcus aureus and Enterococcus faecalis (MIC = 0.42 mg/mL), Pseudomonas aeruginosa (MIC = 34.37 mg/mL), Paenibacillus apiarus (MIC = 4.29 mg/mL) and Paenibacillus thiaminolyticus (MIC = 4.29 mg/mL). Considering mycobacterial inhibition, the best results were obtained by chloroform fraction against M. tuberculosis, M. smegmatis, and M. avium (MIC ranging from 156.25 to 625 μg/mL). This study proves, in part, that the popular use of C. ambrosioides L. can be an effective and sustainable alternative for the prevention and treatment of diseases caused by various infectious agents.

Effect of Uncaria tomentosa extract on purinergic enzyme activities in lymphocytes of rats submitted to experimental adjuvant arthritis model.

BackgroundConsidering that adjuvant arthritis is an experimental model of arthritis widely used for preclinical testing of numerous anti-arthritic agents, which were taken by a large number of patients worldwide, it is of great interest to investigate the therapeutic action of compounds with anti-inflammatory properties, such as Uncaria tomentosa extract. Moreover, there are no studies demonstrating the effect of U. tomentosa on the metabolism of adenine nucleotides published so far. Thus, the purpose of the present study is to investigate the effects of U. tomentosa extract on E-NTPDase and E-ADA activities in lymphocytes of Complete Freund’s Adjuvant (CFA) arthritis induced rats.MethodsTo evaluate the effect of U. tomentosa extract on the activity of E-NTPDase and ADA in lymphocytes, the rats were submitted to an experimental adjuvant arthritis model. Peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Data were analyzed by a one- or two-way ANOVA. Post hoc analyses were carried out by the Student-Newman-Keuls (SNK) Multiple Comparison Test.ResultsE-NTPDase activity was increased in arthritic untreated. Arthritic rats which received U. tomentosa extract, presented similar results to the control group. However, results obtained for adenosine hydrolysis by E-ADA were not altered in arthritic rats. U. tomentosa extract did not alter E-NTPDase and E-ADA activity in healthy animals.ConclusionsThe present investigation supports the hypothesis that the increased E-NTPDase activity verified in arthritic rats might be an attempt to maintain basal levels of ATP and ADP in the extracellular medium, since the arthritis induction causes tissue damage and, consequently, large amounts of ATP are released into this milieu. Also, it highlights the possibility to use U. tomentosa extract as an adjuvant to treat arthritis.

Development and Validation of an HPLC-DAD Analysis for Flavonoids in the gel of Scutia buxifolia

Recent interest in flavonoids has increased greatly due to their biological and pharmacological activities. Flavonoids consist of a large group of low molecular weight polyphenolic substances, naturally occurring in fruits, vegetables and tea, and are an integral part of the human diet. Quercetin and rutin are bioactive markers of Scutia buxifolia and no analytical methods reported so far, associated with quality control of polyherbal formulations containing this species. Therefore, there is a need to develop a sensitive, simple, rapid and reliable method that can simultaneously determine these markers in their combinations. A high-performance liquid chromatography method has been developed and validated as per ICH guidelines. The chromatographic analysis was performed using a C18 column, the mobile phase system consisted of acetonitrile-water (70 : 30, v/v) containing 0.5% (v/v) phosphoric acid and quercetin and rutin were quantificadoa to 356 nm. The proposed method for the quantification of quercetin and rutin in the S. buxifolia fraction (EaSb) and gel was linear, sensitive, precise, specific, accurate and robust. This validated method can be used to control the quality of the EaSb and the gel.

Genotoxic evaluation, secondary metabolites and antioxidant capacity of leaves and roots of Urera baccifera Gaudich (Urticaceae)

In addition to phenolics, flavonoids, flavonols, alkaloids and condensed tannins, our tests identified the antioxidant and genotoxic properties in the crude extract (CE) and fractions of Urera baccifera (Urticaceae) roots and leaves. Oxalic acid (OA) content was determined by HPLC-DAD, which presented high values in the roots (1.82 ± 0.21, 1.79 ± 0.22 and 1.38 ± 0.15 mg/g in butanolic, CE and ethyl acetate fraction, respectively). OA caused a 30.7% reduction in the leucocyte proliferation, followed by butanolic fractions of roots (24.15%) and leaves (23.28%). The mitotic index was lower in butanolic fractions of leaves (8.7%) and roots (8.3%), similar to the OA index, which was 6.0%. The DNA damage index in cultured leukocytes was observed for OA (19.33) and butanol fraction treatments (22.67 and 16, respectively, for leaves and roots). Antioxidant capacity (DPPH and TBARS) was moderated, which was confirmed by the low phenolic, flavonol and flavonoid contents in both parts of the plant.

Antimicrobial Activity and Chromatographic Analysis of Extracts from Tropaeolum pentaphyllum Lam. Tubers

Background: Tropaeolum pentaphyllum Lam. tubers (Tropaeolaceae) are known and used as a condiment and for the treatment of skin infections in Southern Brazil. However, its activity and composition has not yet been investigated. Thus, different extracts and the essential oil from the tubers were tested against a range of microorganisms. The most active extracts were submitted to chromatographic analysis. Methods: Hydroalcoholic extract (70%), fractions of it, and the essential oil from the tubers were tested against several bacteria, yeasts and molds, furnishing the corresponding inhibitory, bactericidal and fungicidal minimal concentration values. The most active extracts were submitted to GC-MS investigation. Results: The strongest effects against different strains of microorganisms, such as Gram-positive and negative bacteria, Candida spp. and dermatophytes were observed for the essential oil and the chloroform fraction, with minimal inhibitory concentrations (MICs) well below 200 µg/mL. GC-MS analysis revealed that the major essential oil constituent is benzyl isothiocyanate (BITC), while the chloroform fraction is constituted of BITC, amides, sulfur, fatty acids and its esters, all compounds that may be related to the demonstrated activity. Conclusions: Overall, the results support the popular use of the plant for the treatment of skin infections, and revealed the main active compounds.