Phytochemical characterisation, antioxidant capacity, and in vitro toxicity of Richardia brasiliensis gomes crude extracts.

Richardia brasiliensis is a species used in folk medicine and rich in active compounds. In this study, the extracts were submitted to UHPLC-ESI-MS/MS analysis and total polyphenols, tannins, and flavonoids assays. Besides, it was determined its antioxidant capacity, oxidative stress markers and toxicological profile. Fourteen polyphenols were found and, in the dosages, a slight change in the concentrations in each extract was observed. Regarding the antioxidant capacity, the responses were different in the methods used. There was an increase in lipid peroxidation, and NO, however total ROS remained unchanged. The cells remained more than 90% viable and the extracts did not cause damage to single strands of DNA, with the exception of the crude autumn and spring extracts at 500 µg/mL. The results found in this study suggest that extracts are potentially toxic to human leukocyte cells in high concentrations; however, more studies should be performed in different cell lines.

Influence of Harvest Season and Cultivar on the Variation of Phenolic Compounds Composition and Antioxidant Properties in Vaccinium ashei Leaves.

The effect of variation of harvest season and cultivar on the total phenolic content (TPC), total flavonoid content (TFC), HPLC-UV/DAD profile and antioxidant properties in Vaccinium ashei (Rabbiteye blueberry) leaves grown in Brazil was evaluated. The cultivars collected in December and March were Aliceblue, Powderblue, Climax, Bluegem and FloridaM. It was observed that leaves from March had the highest TPC values (222 ± 1 mg gallic acid equivalents/g to Aliceblue cultivar) and highest TFC values (49.8 ± 0.8 and 48.7 ± 0.7 µg rutin/g to Clímax and Powderblue cultivars, respectively). The chromatographic profile was quantitatively similar, however, the proportions of each compound were influenced by cultivar and harvest season. Chlorogenic acid and rutin were the main identified phenolic compounds, but chlorogenic acid was the most abundant in both harvest seasons. Antioxidant capacities values ranged from 5.80 ± 0.04 to 105 ± 2 µg/mL (DPPH) and 178 ± 5 to 431 ± 8 mmol Trolox/100 g (ORAC). The cultivar Bluegem by March had the highest values in both assays. The results indicate that the blueberry leaves from different cultivars and harvest seasons have different phenolic compounds content and different antioxidant capacities. In addition, the antioxidant properties demonstrated a high correlation with rutin content.

Antimicrobial, antitrypanosomal and antibiofilm activity of Equisetum hyemale.

This study evaluates, for the first time, the antibiofilm, antimicrobial and antiparasitic potential of crude extract and fractions of stems of Equisetum hyemale against several infectious agents (bacteria, fungi, Mycobacterium and Trypanosomes) by broth microdilution technique and investigates the phenolic composition of the plant by high performance liquid chromatography. The crude extract and fractions showed antimicrobial activity, as they were capable of inhibiting the growth of bacteria in minimal inhibitory concentrations (MICs) ranging from 52.4 mg/mL to 3.27 mg/mL. For Candida species, the MICs ranged from 52.4 mg/mL to 6.5 mg/mL, and for Mycobacterium species from 2.5 mg/mL to 0.625 mg/mL. The dichloromethane fraction was able to reduce 83% of Pseudomonas aeruginosa biofilm formation and 51% of Candida albicans biofilms. The n-butanol fraction presents an important protozoal effect, reducing 100% of Trypanosoma evansi trypomastigotes after 9 h of exposure. The HPLC analysis revealed that the major substances are rosmarinic acid in dichloromethane fraction (7.38 ± 0.08 mg/g FS) and chlorogenic acid in ethyl acetate fraction (8.4 ± 0.26 mg/g FS). The crude extract and fractions of E. hyemale can be both useful and effective agents as a sustainable alternative for the treatment and prevention of several infectious agents.

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.

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

BACKGROUND: Considering 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. METHODS: To 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. RESULTS: E-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. CONCLUSIONS: The 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.

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.

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.