Heteromorphic stamens are differentially attractive in Swartzia (Fabaceae).

The division of labour hypothesis between stamens has explained the evolution of divergent functions between dimorphic stamens in the same flower. However, little is known about whether the distinct type of stamens differs in attractiveness to pollinators. Therefore, we investigate whether the two types of stamens commonly found in Swartzia have different visual and olfactory attractants. We performed observations of anthesis dynamics, registration and collection of floral visitors, measurements of reflectance of floral parts and chemical analysis of the volatile organic compounds of the floral parts of two species, S. flaemingii and S. simplex. Both species have two distinct sets of stamens: one with smaller and abundant stamens in the centre of the flower and the other with fewer but larger abaxial stamens. The sets differ in UV reflectance (only S. simplex) and exhibit a distinct chromatic contrast. Concerning olfactory attractiveness, aliphatic compounds make up most of the odour of the two species, both whole flowers and most of their floral organs. On the other hand, only S. simplex presented apocarotenoids (as ionones) and benzenoids. Furthermore, there are differences in the proportion of volatiles emitted by the stamen in both cases, as the high proportion of sesquiterpenes among the smaller stamens compared to the larger ones. In conclusion, the two types of stamens found in S. flaemingii and S. simplex show a distinct attractiveness. In addition, our data have demonstrated diverse ways of differential attractiveness both between distinct stamens set per flower and between the two species from the same pollen flowers genus.

New natural diterpene-type abietane from Tetradenia riparia essential oil with cytotoxic and antioxidant activities.

Tetradenia riparia (Hochstetter) Codd belongs to the Lamiaceae family and it was introduced in Brazil as an exotic ornamental plant. A previous study showed its antimicrobial, acaricidal and analgesic activities. Two compounds were isolated from essential oil of T. riparia leaves and identified as 9ß,13ß-epoxy-7-abietene (1), a new one, and 6,7-dehydroroyleanone (2), already reported for another plant. The structure of these compounds was determined by spectroscopic analysis and by comparison with literature data. The cytotoxic activities of the essential oil and compounds 1 and 2 were determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, and by tumor cells MDA-MB-435 (human breast carcinoma), HCT-8 (human colon), SF-295 (human nervous system) and HL-60 (human promyelocytic leukemia). The essential oil and compound 1 showed high cytotoxic potential of the cell lines SF-295 (78.06% and 94.80%, respectively), HCT-8 (85.00% and 86.54%, respectively) and MDA-MB-435 (59.48% and 45.43%, respectively). Compound 2 had no cytotoxic activity. The antioxidant activity was determined by 2,2-diphenyl-1-picryl-hydrazyl (DPPH), ß-carotene-linoleic acid system and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The inhibitory concentration (IC50 in µg mL-1) for essential oil and compound 2 was, respectively 15.63 and 0.01 for DPPH; 130.1 and 109.6 for ß-carotene-linoleic acid and 1524 and 1024 for ABTS. Compound 1 had no antioxidant activity. By fractioning the oil, it was possible to identify two unpublished compounds: 1 with high cytotoxic potential and 2 with high antioxidant potential.

LC-MS based screening and targeted profiling methods for complex plant: coffee a case study.

In the recent years the way of thinking about human health necessarily passes by human food. Recent discoveries are not only concerned about valuable biomolecules but also contaminants. Thus, the screening of substances in animal and vegetable matrices by analytical techniques is focused on the presence and absence of target substance. In both cases, the majority of these substances are present as traces or in very low levels. Contaminants could be naturally present in the food, inserted on it or even developed on it as a consequence of food processing or cooking. Pesticides, mycotoxins, dioxins, acrylamide, Sudan red, melamine and now 4(5)-methylimidazole can be, at present, be listed as some of the world big problems related to food contaminants and adulterants. With the development of liquid chromatography coupled to mass spectrometry (LC-MS-MS), in the last few decades, analysis of some food contaminants in trace levels trace become less laborious, more accurate and precise. The multiple approach of those techniques make possible to obtain many results in one single run. On the other hand, European Union (2002/657/EC) established regulations for analytical methods regarding mass spectrometry as detection tool, showing the importance of this technique in food quality control. The EU criteria uses identification points (IPs) that could be achieved basically with four product ions (including molecular ion) or reduced with the use of high resolution equipments. This kind of mass spectrometers made the IPs criteria more accessible, as the exact mass information is a differential tool. In view of this the aim of this review is to present the actual scenario for mass spectrometry analysis in a complex vegetable food matrix such as roasted coffee, with emphasis on needs and challenges regarding the LC-MS technique in order to meet and contribute to food safety standards in this complex matrix.

Protective effects of flavonoids and extract from Vellozia kolbekii Alves against oxidative stress induced by hydrogen peroxide in yeast.

Two flavonoids 3,5,7,3',4'-pentahydroxy-6-prenylflavonol (1) and 3,5,7,3',4'-pentahydroxy-8-methyl-6-prenylflavonol (2) were isolated from the ethyl acetate extract of sheaths of Vellozia kolbekii Alves (Velloziaceae). This is the first time that compound 2 has been described. The crude extract and flavonoids were found to be active as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavengers and were able to the increase tolerance of the eukaryotic microorganism Saccharomyces cerevisiae to oxidative stress generated by H(2)O(2). The protective effect was correlated with a reduction in the oxidation of proteins and lipids. In addition, flavonoids isolated from Velloziaceae showed an inhibitory effect on mutations in p53, which is mutated and nonfunctional in more than 50% of cases of human cancer.

Anti-herpetic activities of chemical components from the Brazilian red alga Plocamium brasiliense.

The CH2Cl2 crude extract and a fraction enriched with halogenated monoterpenes of the Brazilian red alga Plocamium brasiliense were evaluated for cytotoxicity and against the virus HSV-1. The extract showed low cytotoxicity compared with the fraction containing monoterpenes. The crude extract showed, in vitro, a high reduction of infectivity of the virus HSV-1.

Characterization of the antinociceptive and anti-inflammatory activities of fractions obtained from Copaifera multijuga Hayne.

ETHNOPHARMACOLOGICAL RELEVANCE: Copaifera multijuga Hayne (Leguminosae) is a tree that produces an oleoresin, which is extensively commercialized in Brazil as capsules or crude oil for the treatment of several disorders. Ethnopharmacological studies show a diversity of indications such as anti-inflammatory and epidermal wound cicatrization. AIM OF THE STUDY: In the present work three fractions obtained from Copaifera multijuga oleoresin (hexane (HF), chloroform (CF), and methanol (MF) from a KOH impregnated silica gel column chromatography, representing the three main classes of compounds in the Copaifera genus (hydrocarbon sesquiterpenes, oxygenated sesquiterpenes and acidic diterpenes), were evaluated using antinociceptive and anti-inflammatory models. MATERIALS AND METHODS: HF, CF, and MF (doses ranging between 1 and 150 mg/kg, depending on the model used), Copaifera multijuga oleoresin (CMO, 100mg/kg, p.o.) and the reference drug morphine (5mg/kg, p.o.) were evaluated using models for analgesia (acetic acid-induced contortions and tail flick) or inflammation (rat paw oedema and increase in vascular permeability). To elucidate the mechanism of action from the fractions, animals were pre-treated with naloxone (opioid receptor antagonist, 5mg/kg, i.p.). RESULTS: Fractions significantly inhibited (in a concentration-dependant way) the number of contortions induced by acetic acid and the second phase of formalin-induced licking response. Similar results were observed in the tail flick model. The central antinociceptive effect for HF and CF at the doses of 50 and 100mg/kg was higher than the one observed for morphine (1mg/kg). Administration of naloxone inhibited the antinociceptive effect of fractions indicating that HF, CF, and MF may be acting on opioid receptors. All three fractions also inhibited rat paw oedema and the increase in vascular permeability induced by several phlogistic agents (carrageenan, histamine, and serotonin). CONCLUSIONS: Our results indicate that fractions obtained from Copaifera multijuga Hayne demonstrate an antinociceptive effect probably mediated by opioid receptors, and anti-inflammatory activity through inhibition of histaminergic and serotoninergic pathways.