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The antioxidant activity and bioactive compounds of different blackberry fruit genotypes from the major Brazilian producer region (three cultivars and four selections) were evaluated and compared to the Cherokee cultivar. Phenolic and anthocyanic extracts were obtained and evaluated for each fruit genotype. The phenolic extracts of selections 02/96 and 07/001 presented higher antioxidant activity than those of cultivars in most assays. This activity was partially correlated to the higher amount of total phenolics in these samples. Thus, the phenolic compounds are probably the major responsible for the antioxidant activity in the diphenyl-2-picrylhydrazyl radical scavenging assay (DPPH), ferric reducing antioxidant power (FRAP) assay and thiobarbituric acid reactive substances (TBARS) assay. Quercetin seems to be responsible for the antioxidant activity of blackberry phenolic extracts in the ß-carotene bleaching assay. Concerning anthocyanic extracts, the selection 02/96 and Cherokee cultivar from harvest 2007 had higher antioxidant activity than the other genotypes in most assays. Anthocyanins appear to be the major responsible for the antioxidant activity of anthocyanic extracts in the DPPH and FRAP assays, although ascorbic acid also contributed to the DPPH antioxidant activity. Selection 02/96 appears to have higher antioxidant activity than the commercial cultivars cultivated in the southern Brazil and appears to be promising for nutritional and health purposes.

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Baccharis trimera commonly named 'carqueja', is wide-spread in South America and are used as raw material for herbal medicines. A reversed-phase liquid chromatography (RP-LC) method coupled to diode array detector was developed for the analysis of caffeoylquinic acids (CQAs), the main compounds responsible for its digestive activity. The identity of the quinic acids was established by mass spectrometry and were them: 5-O-[E]-caffeoylquinic acid, 3,4-O-[E]-dicaffeoylquinic acid, 3,5-O-[E]-dicaffeoylquinic acid, 4,5-O-[E]-dicaffeoylquinic acid and a tricaffeoylquinic acid. The RP-LC method for the quantitation of the caffeoylquinic acids was validated according to ICH guidelines, based on the following parameters: linearity, selectivity, robustness, limits of detection and quantification, precision and recovery. Hydroalcoholic extracts were prepared by the maceration of the plant material with ethanol:water 1:1 (v/v) in a 0.1:25 g mL(-1) plant:solvent ratio in a water bath at 40°C. Validation data indicated that the HPLC method proposed is suitable for the analysis of caffeoylquinic acids in B. trimera raw material. The results of the LOD and LOQ analyses for the 5-CQA were 4.1 µg mL(-1) and 12.5 µg mL(-1), respectively, 1.3 µg mL(-1), 3.9 µg mL(-1) for 4,5-diCQA and 1.7 µg mL(-1), 5.1 µg mL(-1) for triCQA. The levels of total CQAs ranged from 2.1 to 4.0 g% (w/w). The influence of season harvest and site collection was also evaluated and variations were observed in the results and can be related to phonologic phase, different locations, seasons and soil. Long term and photostability of plant material were carried out and was observed a stable behavior during the time of the experiments.

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UNLABELLED: Strawberry guava (Psidium cattleianum Sabine) is a native fruit of Brazil widely consumed fresh and used in the food industry. In this context, the present study deals with the chemical characterization and the antioxidant activity of the red (Psidium cattleianum) and yellow (P. cattleianum var. lucidum Hort.) strawberry guava fruits, cultivars Irapuã and Ya-Cy, respectively. Knowledge of chemical composition is fundamental to human nutrition, contributing to the quality of foods. Phenolic compounds in both fruits were analyzed by HPLC-DAD and the total flavonoid content was determined by the Folin-Ciocalteu assay. The antioxidant activity was evaluated by the total reactive antioxidant (TRAP) method. Psidium cattleianum presented a higher content of polyphenolic compounds than P. cattleianum var. lucidum (501.33 and 292.03 mg/100 g, respectively), with hyperoside being one of the major flavonoids identified for both cultivars. In addition to flavonoids, P. cattleianum presented an anthocyanin, identified as cyanidin. The antioxidant activity varied in a concentration-dependent manner for both strawberry guava species. The volatile oils in fruits and fatty acids in seeds were quantified by GC-EM. The analysis of the essential oil of yellow strawberry guava was compared with a previous study on the red cultivar, revealing ß-caryophyllene as the main component in both oils. The fatty acid composition was also quite similar and was especially characterized by the presence of unsaturated fatty acids (86.25% and 76%, respectively), among which linoleic acid as the most abundant. PRACTICAL APPLICATION: In this study, the chemical characterization and the antioxidant activity of the red (Psidium cattleianum) and yellow (P. cattleianum var. lucidum Hort.) strawberry guava fruits were investigated. This is important for potential application of strawberry guava as functional food. Moreover, it may be the experimental basis for further development and use in food industry.

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Fruits of Myrcianthes pungens Berg. Legr. (Myrtaceae), known as guabiju, are widely consumed fresh as well as dried, processed into jam, marmalade, and juices. In this study, chemical composition and antichemotactic and antioxidant activities of fruits from a wild type (GB) and 2 genotypes, PL2 and PL1, of guabiju were investigated. Total anthocyanins for the genotypes ranged from 334 to 531 mg/100 g dry weight (dwt). Total flavonoids and polyphenols ranged from 79.8 to 154 mg/100 g and 2438 to 4613 mg/100 g (dwt), respectively. A reversed phase liquid chromatography method with photodiode array detection was used to determine chemical profiles of the main anthocyanins found in the extracts. An HPLC method for the quantification of flavonoids is proposed, providing a simple procedure with rapid sample preparation. All samples contained 5 identical anthocyanidins, distributed differently, with cyanidin as the main compound. Identified flavonoids were quercitrin, hyperoside, and isoquercitrin; their relative amounts varied among the extracts. The antioxidant activity of guabiju methanolic extract was comparable to that of Trolox, and at a test concentration of 0.25 mg/mL, GB and PL2 activities were higher than those exhibited by Trolox. Total dry extracts of guabiju exhibited greater inhibition of chemotaxis at a concentration of 4 µg/mL, except for GBH (wild-type hydrolyzed extract) which already presented high values at a concentration of 2 µg/mL. These results suggest that the consumption of this fruit, rich in polyphenols, may be beneficial to human health. Practical Application: The paper is the first attempt on the improvement of this native fruit, since it is widely consumed regularly as part of the South American diet. The content of phenolic compounds demonstrates that consumption of guabiju would be beneficial to human health. Differences among samples, originating from open pollination of plants growing on the same site, lead to the conclusion that improvements can be made in the chemical composition and beneficial activity of guabiju fruits by simply selecting genotypes for these characteristics among open-pollinated seedlings.

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Citrus aurantium (bitter orange) is characterized by the presence of p-synephrine, an amine structurally and pharmacologically related to ephedrine. Besides the same adverse effects as ephedrine, nowadays it is believed that altered levels of p-synephrine can be associated to the occurrence of migraine and cluster headaches. Leaves and fruits of this species are highly commercialized in form of teas and herbal preparations, but without taking into account the risks associated with its use. This work describes a survey of teas and herbal preparations containing C. aurantium, commercialized in Porto Alegre (RS/Brazil), in order to verify the presence of p-synephrine. Comparing with the mean amount available in the supermarkets, around 20 percent of the teas and 10 percent of the herbal preparations declared the presence of C. aurantium in their labels. In a sampling of 15 teas and 2 herbal preparations selected for the analysis, the presence of p-synephrine was characterized in all samples, with levels between 0.0040 to 0.2308 percent, leading to a caution that even being natural products, they are not free of adverse effects.

Citrus aurantium (laranjeira-azeda) é caracterizada pela presença de p-sinefrina, amina estrutural e farmacologicamente similar à efedrina. Além de poder causar efeitos adversos similares aos da efedrina, atualmente acredita-se que níveis endógenos alterados de p-sinefrina possam estar associados à causa da enxaqueca. Folhas e frutos desta espécie são largamente comercializados na forma de chá e em preparados de erva-mate, sem que sejam considerados os riscos associados ao seu uso. Neste sentido, este trabalho descreve uma pesquisa em chás e preparados de erva-mate comercializados em Porto Alegre, para verificar a presença de C. aurantium e p-sinefrina. Comparando com a quantidade média disponível nas prateleiras dos supermercados, cerca de 20 por cento dos chás e 10 por cento dos preparados de erva-mate declaravam nos rótulos conter C. aurantium. De uma amostragem de 15 chás e 2 preparados de erva-mate selecionados para análise, em todos foi caracterizada a presença de p-sinefrina com níveis variando de 0,0040 a 0,2308 por cento, levando ao alerta de que mesmo sendo naturais, estes produtos podem não ser destituídos de reações adversas.

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Aqueous and hydro-ethanolic extracts of Bauhinia microstachya leaves (AEBM and HEBM) were investigated for their phenolic content and phytochemical profile (by spectrophotometry and HPLC), and for their antioxidant activities and free radical scavenging potential in different in vitro systems (TRAP, TEAC, TBARS, nitric oxide, superoxide and hydroxyl radical). HEBM presented a 27.4% higher content of phenolics when compared to AEBM and a distinct phytochemical profile was observed. Our work suggests that both extracts have potent antioxidant activities and that their antioxidant capacity and efficiency vary according to the radical-generating system. In general, HEBM was more effective than AEBM in avoiding ROS-generating damage and in scavenging the various radicals formed. Nevertheless, when results were normalized to total phenolic content, a different profile of antioxidant activities and free radical scavenging potential was observed, particularly against oxidative lipid damage and superoxide radical. B. microstachya extracts may be considered an interesting source of natural antioxidants as well as other phenolic-rich plants.

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A influência de fatores tecnológicos, como método de extração, relação droga:solvente e natureza do líquido extrator sobre o teor de resíduo seco, pH, densidade e teor de cumarina foi avaliada em soluções extrativas de Mikania glomerata Sprengel. Entre as proporções droga:solvente testadas, aquela de 1,5:10 foi selecionada, com base nos rendimentos bruto de extração (resísuo seco) e de cumarina. Na comparação entre métodos de extração, percolação e refluxo, mistura hidroetanólica 50 por cento (v/v) ou etanol 96 por cento (v/v) foram utilizados como líquidos extratores. As quatro soluções extrativas obtidas foram designadas soluções extrativas hidroetanólicas preparadas por percolação (SEHEP) ou por refluxo (SEHER) e soluções extrativas etanólicas preparadas por percolação (SEEP) ou por refluxo (SEER)...

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