Melipona subnitida (“jandaíra”) is a species of stingless bee endemic to the Caatinga, a dry forest in the northeastern Brazilian semi-arid. Propolis is a product containing beeswax and plant resin. It contains compounds that can be able to prevent health problems by protecting cells against damage by oxidative agents. M. subnitida produces geopropolis, a mixture of propolis with soil. Samples of geopropolis of M. subnitida, one of inside and another outside of the nest from a hive in the municipality of Mossoró (northeastern Brazil) were analyzed by HPLC-PDA-ESI-MS/MS and their antioxidant activity evaluated by the DPPH and β-carotene/linoleic acid methods. Both samples exhibited similar chemical profile, characterized by 26 phenolic compounds, however, the compounds detected were more abundant in sample collected from inside of the nest. They were tentatively characterized as galloyl hexoses, coumaroyl-O-galloyl-hexoses, cinnamoyl-O-galloyl-hexoses, coumaroyl- and cinnamoyl- galloyl hexoses, phenylpropanoyl-O-benzoyl hexoses, flavanones and ellagitannins. Flavonoids, galloyl hexoses, coumaroyl-O-galloyl-hexosides, cinnamoyl-O-galloyl-hexosides and coumaroyl-cinnamoyl-galloyl hexosides were reported previously in this genus, however ellagitannins and phenylpropanoyl-O-benzoyl hexoses are reported for the first time. Comparing the antioxidant activity of the geopropolis samples from inside and outside of the nest, the latter was higher than the former.

Resumo: Durante a embriogênese e deposição de reservas, sementes em desenvolvimento apresentam metabolismo fortemente ativo, enquanto na fase de dessecação de sementes tolerantes é esperado metabolismo reduzido. Sementes de Poincianella pluviosa apresentam um ciclo de maturação extenso (11 meses), maior que sua longevidade à temperatura ambiente (8 meses). O perfil metabólico dessas sementes foi caracterizado durante a maturação e secagem, enfocando seus papéis no comportamento das sementes após dispersão. Respostas distintas de eixos embrionários e cotilédones à secagem foram observadas dependendo do estádio de desenvolvimento. Baixas proporções de intermediários de ácidos tricarboxílicos até a maturidade indicaram um baixo metabolismo respiratório anterior à fase de dessecação. Mudanças nas proporções de chiquimato, 4-cumarato e quinato sugerem uma alteração metabólica em direção a síntese de isômeros clorogenatos, encontrados em altas proporções em sementes dispersas. Altas proporções de lactato e glicerol foram observadas em sementes imaturas após secagem artificial, mas também em eixos naturalmente secos de sementes dispersas. Isso sugere um metabolismo ativo anterior à dessecação e um estresse osmótico sob hipóxia, mecanismos nunca descritos antes em sementes tolerantes à dessecação. Nossos resultados indicam que sementes de P. pluviosa podem ser dispersas com um desligamento metabólico incompleto, que pode estar relacionado à sua baixa longevidade.

Abstract: During embryogenesis and seed filling, developing seeds are metabolically highly active, while at the desiccation stage of tolerant seeds a decreased metabolism is expected. Seeds of Poincianella pluviosa present an extensive maturation cycle (11 months), longer than seed storability at room temperature (8 months). The metabolic profile of these seeds was characterized during maturation and drying, focusing in their role on seed behavior after shedding. Distinct responses of the embryonic axes and cotyledons to drying were observed depending on the developmental stage. Low proportions of tricarboxylic acids intermediaries until maturity indicated a low respiratory metabolism prior to the desiccation stage. Changes in shikimate, 4-coumarate, and quinate proportions suggest a metabolic shift towards the synthesis of chlorogenate isomers, found in high proportions in dispersed seeds. High proportions of lactate and glycerol were observed in immature seeds after artificial drying, but also in naturally dried axes of dispersed seeds. This suggests an active metabolism prior to drying and an osmotic stress under hypoxia, mechanisms that were never described before in desiccation-tolerant seeds. The results indicated that P. pluviosa seeds are dispersed with an incomplete metabolic switch-off, which can be related to their short lifespan.

ABSTRACT Propolis (bee glue) a product of Apis mellifera L. is a resinous mixture containing chiefly beeswax and resin harvested by bees from plant leaves, buds and exudates. Extracts of a propolis sample from Salitre, a municipality of Ceará state (northeast Brazil) were obtained with solvents of increasing polarity (hexane, chloroform, ethyl acetate and methanol). A chemical profile was carried out by GC–EI-MS and HPLC–DAD–ESI-MS/MS. Lupenone, lupeol, octanoic acid tetracosyl ester and octanoic acid hexacosyl ester were identified by GC–EI-MS. Antioxidant activity was evaluated by the DPPH and β-carotene discoloring methods, and anti-HIV activity by the in vitro inhibition of HIV-1 reverse transcriptase. The ethyl acetate extract exhibited the highest antioxidant and anti-HIV activity and was fractioned by column chromatography using silica gel and seven different eluents. The active fractions were submitted to semi preparative HPLC and the following compounds were isolated: caffeic acid, p-coumaric acid, diprenylcinnamic acid, quercetin, naringenin, isorhamnetin, quercetin-3-O-diglucoside,4,2′,4′-trihydroxy-2-methoxychalcone, gossypetin-3,3′,4′,7-tetramethyl ether, myricetin-3,7,3′-trimethyl ether and 5-hydroxy-3,6,7,8,4′-pentamethoxyflavone. The ethyl acetate extract and its fractions F5-F7, as well as quercetin, isorhamnetin, myricetin-3,7,3′-trimethyl ether and p-coumaric acid exhibited high antioxidant activity on both DPPH and β-carotene antioxidant methods. Isorhamnetin exhibited moderate inhibitory effect against HIV-1 reverse transcriptase (56.99 ± 3.91%), followed by naringenin (44.22 ± 1.71%), quercetin (43.41 ± 4.56%) and diprenylcinnamic acid (41.59 ± 2.59%). These results agree with previous authors who reported anti-HIV activity of flavonoids.

O presente trabalho relata resultados sobre a ação do Potato virus X (PVX) no conteúdo de fenóis totais e alcalóides em folhas de Datura stramonium. Uma diminuição significativa no conteúdo dessas substâncias foi observada nas folhas inoculadas com o PVX (X-I). Entretanto, houve um aumento na porcentagem de fenóis nas folhas friccionadas com tampão fosfato (C1-I) e nas acima das friccionadas, possivelmente induzido por injúria mecânica. Cromatografia gasosa/espectroscopia de massas revelou quantidades de escopolamina nas amostras submetidas a todos os tratamentos, exceto em X-I, no qual a quantidade deste alcalóide foi baixa. Altas quantidades de uma substância não identificada (íon molecular m/z 302 e um proeminente pico a m/z 129) foram notadas em extratos a partir de folhas dos tratamentos X-I, C1-I e nas acima das inoculadas com o PVX. Sugere-se que a síntese e acúmulo da substância não identificada é um resultado do estresse causado pela injúria mecânica e pelo vírus.

The present paper reports results of the effect of Potato virus X (PVX) on the contents of total phenols and alkaloids in leaves of Datura stramonium. A significant decrease in the contents of phenols and alkaloids was observed in leaves inoculated with PVX (X-I). However, there was an increase in the percentage of phenols in leaves rubbed with phosphate buffer (C1-I) and in leaves from the nodes immediately above, possibly induced by mechanical injury. Gas chromatography/mass spectroscopy revealed amounts of scopolamine in samples submitted to all treatments, except X-I, in which the amount of this alkaloid was low. High amounts of an unidentified compound (molecular ion m/z 302 and a prominent peak at m/z 129) were noted in extracts from leaves X-I, C1-I and leaves from the nodes immediately above the leaves inoculated with PVX. It is suggested that the synthesis and accumulation of the unidentified compound is a result of stress from mechanical injury and virus inoculation.

Hipóteses são apresentadas sobre a evolução de padrões estruturais de metabólitos secundários (flavonóides e alcanos de ceras foliares) e ácidos graxos, em famílias bem representadas nos campos rupestres. A distribuição de ácidos graxos é comentada no confronto entre os gêneros de Lythraceae, com maior ênfase em Cuphea (supostamente mais avançado) e Diplusodon, com a proposta de que compostos saturados com cadeias curtas representam uma condição derivada em Lythraceae, embora restrita provavelmente a Cuphea. A evolução deve ter gerado perfis flavonoídicos mais complexos em Cuphea, com a inclusão de C-glicoflavonas e flavonóis metoxilados (ramnetina e isoramnetina), ausentes em representantes de Diplusodon e Lafoensia. Ao contrário, grupos supostamente primitivos de Eriocaulaceae (Paepalanthus, por exemplo) apresentam perfis flavonoídicos mais complexos, caracterizados por flavonas e flavonóis, estes últimos freqüentemente com hidroxilação e metoxilação no carbono 6; alguns grupos mais avançados da mesma família (Leiothrix e Syngonanthus) aparentemente possuem apenas flavonas, com uma tendência ao maior acúmulo de C-glicoflavonas nas espécies de menor porte. Em Velloziaceae, os representantes da subfamília supostamente primitiva (Vellozioideae) apresentam preferencialmente distribuições de alcanos da cera foliar epicuticular com modas em C27, C29 ou C31; os representantes da subfamília derivada (Barbacenioideae) apresentam modas preferencialmente em C33 ou C35. No entanto, no gênero Pleurostima (Barbacenioideae) as modas recaem geralmente em C31. As condições de avanço ou primitividade dos perfis de metabólitos secundários são comparadas com resultados de análises cladísticas baseadas em caracteres morfológicos (Eriocaulaceae e Lythraceae) e morfológicos e moleculares (Velloziaceae).

Hypotheses are presented on the evolution of structural patterns of secondary metabolites (flavonoids and foliar wax alkanes) and fatty acids of families of "campos rupestres". The distribution of fatty acids is given for genera of Lythraceae, with emphasis on Cuphea (supposedly more advanced) and Diplusodon. Compounds with saturated short chains represent a derived condition in Lythraceae although they are probably restricted to Cuphea. It is suggested that evolution selected for more complex flavonoid patterns in Cuphea, with the inclusion of C-glycoflavones and methoxylated flavonols (rhamnetin and isorhamnetin), which are not found in members of Diplusodon and Lafoensia. The supposedly primitive groups of Eriocaulaceae (e.g., Paepalanthus) presented more complex flavonoid patterns characterized by flavones and flavonols, the latter frequently being 6-hydroxylated or methoxylated. More advanced groups of Eriocaulaceae (e.g., Leiothrix and Syngonanthus) apparently possess only flavones, C-glycoflavones are a salient feature of species with smaller habits. In Velloziaceae, members of the primitive subfamily Vellozioideae show distribution of alkanes of foliar epicuticular wax in which C27, C29 or C31 predominate; members of the derived subfamily Barbacenioideae usually show distributions with a predominance of C33 or C35, while species of Pleurostima (Barbacenioideae) have C31 as the main homologue, thus being intermediate between the two subfamilies. It is suggested that the evolution of alkanes in Velloziaceae follows a trend toward elongation of carbon chains. The condition of advanced or primitive chemical patterns is inferred from the results of cladistic analyses based on morphological characters (Eriocaulaceae and Lythraceae), and morphological and molecular characters (Velloziaceae).