Perspectives for Uses of Propolis in Therapy against Infectious Diseases.

Propolis has gained wide popularity over the last decades in several parts of the world. In parallel, the literature about propolis composition and biological properties increased markedly. A great number of papers have demonstrated that propolis from different parts of the world is composed mainly of phenolic substances, frequently flavonoids, derived from plant resins. Propolis has a relevant role in increasing the social immunity of bee hives. Experimental evidence indicates that propolis and its components have activity against bacteria, fungi, and viruses. Mechanisms of action on bacteria, fungi, and viruses are known for several propolis components. Experiments have shown that propolis may act synergistically with antibiotics, antifungals, and antivirus drugs, permitting the administration of lower doses of drugs and higher antimicrobial effects. The current trend of growing resistance of microbial pathogens to the available drugs has encouraged the introduction of propolis in therapy against infectious diseases. Because propolis composition is widely variable, standardized propolis extracts have been produced. Successful clinical trials have included propolis extracts as medicine in dentistry and as an adjuvant in the treatment of patients against COVID-19. Present world health conditions encourage initiatives toward the spread of the niche of propolis, not only as traditional and alternative medicine but also as a relevant protagonist in anti-infectious therapy. Production of propolis and other apiary products is environmentally friendly and may contribute to alleviating the current crisis of the decline of bee populations. Propolis production has had social-economic relevance in Brazil, providing benefits to underprivileged people.

How diverse is the chemistry and plant origin of Brazilian propolis?

Propolis is a honey bee product containing chiefly beeswax and resins originated from plant buds or exudates. Propolis resin exerts a diversity of biological activities, such as antitumoral, anti-inflammatory, antimicrobial, and defense of the hive against pathogens. Chemical standardization and identification of botanical sources is crucial for characterization of propolis. Types of Brazilian propolis are characteristic of geographical regions and respective biomes, such as savannas (Cerrado), mangroves, dry forest (Caatinga), rain forests (Amazon, Atlantic, and Interior forests), altitudinal fields ("Campos Rupestres"), Pantanal, and Araucaria forests. Despite the wide diversity of Brazilian biomes and flora, relatively few types of Brazilian propolis and corresponding resin plant sources have been reported. Factors accounting for the restricted number of known types of Brazilian propolis and plant sources are tentatively pointed out. Among them, the paper discusses constraints that honey bees must overcome to collect plant exudates, including the characteristics of the lapping-chewing mouthpart of honey bee, which limit their possibilities to cut and chew plant tissues, as well as chemical requirements that plant resins must fulfil, involving antimicrobial activity of its constituents and innocuity to the insects. Although much still needs to be done toward a more comprehensive picture of Brazilian propolis types and corresponding plant origins, the prospects indicate that the actual diversity of plant sources of honey bee propolis will remain relatively low.

Contents of tannins of cultivars of sorghum cultivated in Brazil, as determined by four quantification methods.

High tannin content in sorghum grains is an undesirable characteristic for poultry and pig feeding and represents a challenge for breeding programs. On the other hand, moderate content of tannins in sorghum may be beneficial in human diets because they exert anti-cancer, anti-inflammatory and reduced carbohydrate uptake effects, among others. The aim of this study was to compare tannin contents of twenty sorghum cultivars available in Brazil, as well as to compare results obtained with four methods of tannin quantification: butanol/HCl, vanillin/HCl, BSA/FeCl3 and PVPP/Folin-Ciocalteu. The results obtained with butanol/HCl and vanillin/HCl were higher than with BSA/FeCl3 and PVPP/Folin-Ciocalteu. A known amount of purified quebracho tannin was used to test the validation of methods of tannin quantification and vanillin/HCl stood out for its high accuracy degree. The sampling used reveals wide genetic diversity regarding tannin contents. The expectation of predicting tannin contents on basis of grain color seems unfeasible.

Chemical composition and antimycoplasma activity of a brown propolis from southern Brazil.

Extracts of a sample of brown propolis produced in the district of Itapará (Southern Brazil) were obtained with solvents with increasing polarity. The extracts were analyzed by RPHPLC-DAD-ESI-MS/MS and evaluated toward activity against Mycoplasma bovis, M. gallisepticum, M. genitalium, M. hominis, M. hyorinis, M. penetrans and M. pneumonieae. Typical components of "alecrim-do-campo" propolis (e.g. prenylated phenylpropanoids and caffeoyl-quinic acids) were characterized in the analyzed extraccts, in addition to several flavonols. Less polar extracts showed higher anti-mycoplasma activity (MIC value commonly 3.9 µg/mL) than alcoholic and aqueous extracts (MIC value often 7.8-250 µg/mL). The results indicate that Itapará propolis is a promising source for the development of therapeutic drugs.

Evaluation of DNA markers for molecular identification of three Piper species from Brazilian Atlantic Rainforest.

Piper is one of two large genera in the Piperaceae, and with ca. 2600 species, is one of the largest plant genera in the world. Species delimitation and evaluation of genetic diversity among populations are important requisites for conservation and adequate exploitation of economically important species. DNA barcoding has been used as a powerful tool and a practical method for species characterization and delimitation. The present work aims to evaluate molecular markers for barcoding three Piper species native to Brazil: P. gaudichaudianum ("jaborandi" or "pariparoba"), P. malacophyllum ("pariparoba-murta") and P. regnellii ("caapeba" or "pariparoba"). A reference DNA barcode library was developed using sequences of three candidate regions: ITS2, trnH-psbA and rbcL. Transferability of the microsatellite (SSR) primers Psol 3, Psol 6 and Psol 10, designed originally for Piper solmsianum, to the three Piper species was also evaluated. The discriminatory power of the markers was based on the determination of inter- and intraspecific distances, phylogenetic reconstruction, and clustering analysis, as well as BLASTn comparison. Sequences of ITS2 enabled efficient species identification by means of the BLASTn procedure. Based on these sequences, intraspecific divergence was lower than interspecific variation. Maximum Parsimony analyses based on ITS2 sequences provided three resolved clades, each corresponding to one of the three analysed species. Sequences of trnH-psbA and rbcL had lower discriminatory value. Analyses combining sequences of these regions were less effective toward the attainment of resolved and strongly supported clades of all species. In summary, robustly supported clades of P. regnellii were obtained in most of the analyses, based either on isolated or combined sequences. The SSRs primers Psol 3, Psol 6 and Psol 10 were shown to be transferable to P. gaudichaudianum and P. regnellii, but not to P. malacophyllum. Preliminary cluster analyses based on the polymorphism of the amplified products suggested that Psol 3 has lower potential than Psol 6 and Psol 10 for discrimination of Piper species.

Corrigendum to "Antioxidant Activity of a Geopropolis from Northeast Brazil: Chemical Characterization and Likely Botanical Origin".

[This corrects the article DOI: 10.1155/2017/4024721.].

Antioxidant Activity of a Geopropolis from Northeast Brazil: Chemical Characterization and Likely Botanical Origin.

Geopropolis is a product containing wax, plant resin, and soil particles. It is elaborated by stingless bees of tribe Meliponini. Methanol extracts of sample of geopropolis produced by Scaptotrigona aff. depillis [corrected] ("mandaguari") in the state of Rio Grande do Norte (RN, northeast Brazil) were analyzed for the determination of standard parameters (total phenols, total flavonoids, and radical scavenging activity) and chemical characterization by HPLC-DAD-MS/MS analysis. The sample analyzed has high contents of total phenols and flavonoids, as well as high antioxidant activity. The constituents characterized were mainly flavonols, such as quercetin methyl ethers, and methoxychalcones. Such chemical profile is similar to the composition of a green propolis from the same area of RN, which is produced by Africanized Apis mellifera, using shoot apices of Mimosa tenuiflora, popularly known as "jurema-preta." This finding provides evidence that "mandaguari" geopropolis and honeybee propolis have the same botanical origin in RN. The sharing of a plant resin source by phylogenetically distant bees (Apinae and Meliponinae) suggests that bee genetic factors play little role in the choice of plants for resin collection and that the availability of potential botanical sources plays a decisive role.

New propolis type from north-east Brazil: chemical composition, antioxidant activity and botanical origin.

BACKGROUND: Propolis is a bee product with wide diversity of biological activity. It has a complex composition, which is dependent on its botanical source. The present study aimed to determine the chemical profile, antioxidant activity and botanical origin of two samples of a propolis type from two locations of the state of Rio Grande do Norte (RN, north-east Brazil). RESULTS: The standard chemical characteristics of the RN propolis are similar or superior to the internationally marketed Brazilian green propolis. RN propolis from two locations have high antioxidant activity, corresponding to 10% (municipality of Afonso Bezerra) and 13% (municipality of Alto do Rodrigues) of quercetin activity by the 2,2-diphenyl-1-picrylhydrazyl method and to 15% (both locations) by the ß-carotene discoloration method. High-performance liquid chromatography with diode array detection (HPLC-DAD)-electrospray ionization-tandem mass spectrometry analyses revealed that most constituents of the RN propolis are flavonoids, mainly flavonols and chalcones. HPLC-DAD analysis of ethanol extracts revealed a great similarity between the chemical profile of RN propolis and shoot apices of 'jurema-preta' (Mimosa tenuiflora, Leguminosae, Mimosoideae). CONCLUSION: 'Jurema-preta' shoot apices are likely resin sources of RN propolis. The chemical characteristics and antioxidant property of RN propolis provide promising prospects for the introduction of this type of propolis into the apicultural market. © 2017 Society of Chemical Industry.

Quantificação de fenóis, flavonoides totais e atividades farmacológicas de geoprópolis de Plebeia aff. Flavocincta do Rio Grande do Norte / Quantification of phenols, total flavonoids and pharmacological activities of geopropolis Plebeia aff. flavocincta of Rio Grande do Norte, Brazil

Esse estudo objetivou avaliar a composição química e potencial terapêutico do extrato hidroalcóolico de geoprópolis produzidas por abelhas Plebeia aff. flavocincta no semiárido do Rio Grande do Norte. Oito amostras (A-H) foram submetidas a quantificação dos teores de fenóis e flavonoides totais e avaliação da atividade antioxidante através do método DPPH (2,2-difenil-1-picril-hidrazilo). Além disso, foram investigadas as atividades antibacteriana, através do método de difusão em ágar, e a cicatrizante, através da indução de feridas cirúrgicas experimentais em Rattus norvegicus Berkenhout, 1769, linhagem Wistar, tratados com creme à base de geoprópolis. Duas amostras (F e G) se destacaram por apresentar altos valores de fenóis e flavonoides totais. A capacidade antioxidante acima de 90% foi observada em cinco amostras. Os extratos foram considerados eficazes no que se refere a atividade antibacteriana, pois das oito amostras, cinco promoveram a formação de halos de inibição ≥9mm para todas as cepas testadas. Duas amostras (D e G) se destacaram em relação as demais por apresentar excelentes resultados, uma vez que, promoveram a formação de halos de inibição para as bactérias Staphylococcus epidermidis e Escherichia coli, superiores estatisticamente aos valores dos antibióticos controles, quando na concentração de 100%. As amostras A e G promoveram, respectivamente, a formação de halos de inibição, que não diferiram significativamente dos halos produzidos pelos antibióticos controles em todas as concentrações testadas para E. coli e Staphylococcus aureus. A análise do processo de cicatrização sob os pontos de vista clínico, macroscópico e histológico permitiu concluir, que o uso do creme à base de geoprópolis apresentou influência positiva na cicatrização de feridas cutâneas experi­mentais, por promover reação inflamatória menos intensa e fechamento mais rápido das feridas em relação ao grupo controle.(AU)

This study aimed to evaluate the chemical composition and therapeutic potential of the hydroalcoholic extract of geopropolis produced by bees Plebeia aff. flavocincta in Rio Grande do Norte semi-arid. Eight samples (A-H) were submitted to the quantification of total phenols and flavonoid content and evaluation of the antioxidant activity by DPPH method (2,2-diphenyl-1-picryl-hydrazyl). Additionally, antibacterial activities were investigated by agar diffusion method, and healing process by inducing experimental surgical wounds in Rattus norvegicus Berkenhout, 1769, Wistar line, and treated with the geopropolis-based cream. Two samples (F and G) have stood out by presenting high values of total phenols and flavonoids. The antioxidant capacity of over 90% was observed in five samples. The extracts were considered effective in relation to antibacterial activity since of the eight samples, five promoted the formation of inhibition zones ≥9mm above all strains tested. Two samples (D and G) have stood out over the other for presenting excellent results since it promoted the formation of inhibition zones for Staphylococcus epidermidis and Escherichia coli exceeding statistically to the values of the antibiotic controls when the concentration was 100%. Samples A and G have provided, respectively, that the formation of inhibition zones were not significantly different than the halos produced by antibiotics controls at all concentrations tested for Escherichia coli and Staphylococcus aureus. The analysis of the healing process from the clinical, macroscopic and histological points of view, allowed to conclude that the use of geopropolis-based cream had a positive influence on the healing of experimental skin wounds by promoting less intense inflammatory reaction and healing faster from wounds in the control group.(AU)

Antiproliferative activity of flavonoids from Croton sphaerogynus Baill. (Euphorbiaceae).

Croton sphaerogynus is a shrub from the Atlantic Rain Forest in southeastern Brazil. A lyophilized crude EtOH extract from leaves of C. sphaerogynus, obtained by maceration at room temperature (seven days), was suspended in methanol and partitioned with hexane. The purified MeOH phase was fractionated over Sephadex LH-20 yielding five fractions (F1-F5) containing flavonoids, as characterized by HPLC-DAD and HPLC-MS analyses. The antiproliferative activity of the crude EtOH extract, MeOH and hexane phases, and fractions F1-F5 was evaluated on in vitro cell lines NCI-H460 (nonsmall cell lung), MCF-7 (breast cancer), and U251 (glioma). The MeOH phase showed activity (mean log GI50 0.54) higher than the hexane phase and EtOH extract (mean log GI50 1.13 and 1.19, resp.). F1 exhibited activity against NCI-H460 (nonsmall cell lung) (GI50 1.2 µg/mL), which could be accounted for the presence of flavonoids and/or diterpenes. F4 showed moderate activity (mean log GI50 1.05), while F5 showed weak activity (mean log GI50 1.36). It is suggested that the antiproliferative activity of the crude EtOH extract and MeOH phase is accounted for a synergistic combination of flavonoids and diterpenes.

Glands on the foliar surfaces of tribe Cercideae (Caesapiniodeae, Leguminosae): distribution and taxonomic significance.

Large elongated glands occur on Cercideae leaf surfaces. Leaves of Bauhinia (55 taxa, 53 species), Cercis (1 species), Phanera (1 species), Piliostigma (2 species), Schnella (19 species) and Tylosema (1 species) were observed to determine location and relative number of glands. They were only observed on the abaxial leaf surface of 42 Bauhinia taxa. The glands were analyzed by light stereomicroscope and scanning electron microscopy. They are large (up to 270 µm long and 115 µm wide) and multicellular, containing lipophilic substances, probably volatile oils. Presence or absence and density of the glands in species of Bauhinia may be useful to determine species delimitation or distinction among infraspecific taxa. Higher density of glands is more common in species from "cerrado" (a savanna ecosystem) and "caatinga" (a semiarid ecosystem from northeast Brazil) areas. Bauhinia species devoid of foliar glands are frequently from humid forests.

Composition of the volatile fraction of a sample of Brazilian green propolic and its phytotoxic activity.

BACKGROUND: Propolis is a resinous material produced by honeybees, containing mainly beeswax and plant material. Despite the wide spectrum of biological activity of propolis, to our knowledge no studies have been carried out about phytotoxic properties of Brazilian propolis and its constituents. The aims of this study were to analyze the chemical composition and to evaluate the phytotoxic activity of the volatile fraction of a sample of Brazilian green propolis. RESULTS: Main constituents are the phenylpropanoid 3-prenylcinnamic acid allyl ester (26.3%) and the sesquiterpene spathulenol (23.4%). Several other sesquiterpenes and phenylpropanoids, in addition to linalool and α-terpineol (monoterpenes), were also detected. The activity of solutions of the volatile fraction at 1.0, 0.5 and 0.1% was tested on lettuce seeds and seedlings. The solution at 1% inhibited completely the seed germination and solutions at 0.1 and 0.5% reduced the germination rate index. The solution at 0.5% reduced the growth of the hypocotyl-radicle axis and the development of the cotyledon leaf. CONCLUSIONS: The chemical composition of the volatile fraction of this Brazilian green propolis is different from those previously described, and these results may contribute to a better understanding about the chemical variations in propolis. The volatile fraction of Brazilian green propolis influences both germination of seed lettuce and the growth of its seedlings, showing an phytotoxic potential.

Does propolis contain tannins?

Although polyphenols have been reported as common constituents of propolis, tannins have rarely been mentioned as its constituents. Propolis samples from seven localities in Brazil were analyzed for detection of proanthocyanidins (condensed tannins) and determination of the tannin content. Positive reaction for proanthocyanidins was observed for all samples tested. The contents of tannins varied in the range 0.6-4.1%. A high degree of correlation was noted between total phenols and tannin content. Red and green propolis contained high contents of tannins, while in brown propolis the content was lower. It is suggested that the contents of tannins should be a parameter to be considered in propolis characterization.

Antiproliferative activity of methanol extracts of four species of Croton on different human cell lines

Several species of Croton have been described with biological activities, mainly due to diterpenes, alkaloids and/or other secondary metabolites. These activities account for the traditional use of Croton species to treat certain diseases in South America, Asia and Western Africa. The crude methanol extracts obtained from leaves and steam bark of Croton dichrous Müll. Arg., C. erythroxyloides Baill., C. myrianthus Müll. Arg. and C. splendidus Mart. ex Colla were tested for antiproliferative activity against ten human cancer cell lines. Chemical analyses of all extracts were carried out by GC/MS and HPLC/MS/MS. The leaf extract obtained from C. erythroxyloides showed potent activity against PC-3 (prostate) and OVCAR-3 (ovary) cell lines. Lupeol is suggested to be involved in such activity. Tiliroside, an acyl-glycosilated flavonoid ubiquitous in all tested extracts, seems to play an important role in the observed moderate activity of most extracts against the leukemia K562 cell lineage.

Chemical composition and efficacy of dichloromethane extract of Croton sphaerogynus Baill. (Euphorbiaceae) against the cattle tick Rhipicephalus microplus (Acari: Ixodidae).

The cattle tick Rhipicephalus microplus is widely distributed in tropical and subtropical regions, causing high economic impact on cattle production. The control of tick infestations is regarded worldwide as critical and has been based on the use of organophosphates, synthetic pyretroids, amitraz and recently ivermectin and fipronil. The present study reports the analysis by gas chromatography/mass spectrometry of the constituents of leaf extracts of Croton sphaerogynus and results of acaricidal activity against the cattle tick R. microplus. The larval package test using the serial dilutions 0.625%, 1.25%, 2.5%, 5.0%, 10.0% and 20.0% (v/v) gave mortality rates 2.25%, 8.26%, 8.81%, 24.80%, 83.66% and 99.32%, respectively. Relevant constituents identified were abietanes, podocarpenes and clerodane type furano diterpenes. The present work may represent a possibility of attainment of natural substances useful for the control of R. microplus.

Constituents and antiproliferative activity of extracts from leaves of Croton macrobothrys

Croton macrobothrys Baill, Euphorbiaceae, is a tree from the Atlantic Forest in Southern Brazil, used in traditional medicine and popularly known as "dragon's blood" and "pau-sangue". Leaf n-hexane, dichloromethane and methanol extracts were analyzed by GC/MS and evaluated for their in vitro antiproliferative activity on cell lines 786-0 (kidney), HT-29 (colon), K562 (leukemia), NCI-ADR/RES (drug resistant ovary), NCI-H460 (lung), MCF-7 (mammary), PC-3 (prostate), OVCAR-3 (ovary), U251 (glioma) and UACC-62 (melanoma). The dicloromethane extract exhibited activity against all cell lines at the concentration 25 µg/mL, in particular on cell lines NCI-H460 (GI50 0.33 μg/mL) and K5662 (GI50 0.91 μg/mL). Relevant constituents in dichloromethane extract are the alkaloids corydine and salutaridine, as well as the diterpenes geranylgeraniol and crotonin-derived clerodanes.

Nutritional reserves of Vochysiaceae seeds: chemical diversity and potential economic uses.

Contents of proteins, carbohydrates and oil of seeds of 57 individuals of Vochysiaceae, involving one species of Callisthene, six of Qualea, one of Salvertia and eight of Vochysia were determined. The main nutritional reserves of Vochysiaceae seeds are proteins (20% in average) and oils (21. 6%). Mean of carbohydrate contents was 5. 8%. Callisthene showed the lowest protein content (16. 9%), while Q. cordata was the species with the highest content (30% in average). The contents of ethanol soluble carbohydrates were much higher than those of water soluble carbohydrates. Oil contents lay above 20% for most species (30. 4% in V. pygmaea and V. pyramidalis seeds). The predominant fatty acids are lauric (Q. grandiflora), oleic (Qualea and Salvertia) or acids with longer carbon chains (Salvertia and a group of Vochysia species). The distribution of Vochysiaceae fatty acids suggests for seeds of some species an exploitation as food sources (predominance of oleic acid), for other species an alternative to cocoa butter (high contents or predominance of stearic acid) or the production of lubricants, surfactants, detergents, cosmetics and plastic (predominance of acids with C(20) or C(22) chains) or biodiesel (predominance of monounsaturated acids). The possibility of exploitation of Vochysiaceae products in a cultivation regimen and in extractive reserves is discussed.

Nutritional reserves of Vochysiaceae seeds: chemical diversity and potential economic uses

Contents of proteins, carbohydrates and oil of seeds of 57 individuals of Vochysiaceae, involving one species of Callisthene, six of Qualea, one of Salvertia and eight of Vochysia were determined. The main nutritional reserves of Vochysiaceae seeds are proteins (20 percent in average) and oils (21. 6 percent). Mean of carbohydrate contents was 5. 8 percent. Callisthene showed the lowest protein content (16. 9 percent), while Q. cordata was the species with the highest content (30 percent in average). The contents of ethanol soluble carbohydrates were much higher than those of water soluble carbohydrates. Oil contents lay above 20 percent for most species (30. 4 percent in V. pygmaea and V. pyramidalis seeds). The predominant fatty acids are lauric (Q. grandiflora), oleic (Qualea and Salvertia) or acids with longer carbon chains (Salvertia and a group of Vochysia species). The distribution of Vochysiaceae fatty acids suggests for seeds of some species an exploitation as food sources (predominance of oleic acid), for other species an alternative to cocoa butter (high contents or predominance of stearic acid) or the production of lubricants, surfactants, detergents, cosmetics and plastic (predominance of acids with C20 or C22 chains) or biodiesel (predominance of monounsaturated acids). The possibility of exploitation of Vochysiaceae products in a cultivation regimen and in extractive reserves is discussed.

Teores de proteínas, carboidratos solúveis e óleos de sementes de 57 indivíduos de Vochysiaceae, compreendendo uma espécie de Callisthene, seis de Qualea, uma de Salvertia e oito de Vochysia foram determinados. As principais reservas de sementes de Vochysiaceae são proteínas (20 por cento em média) e óleos (21, 6 por cento). A média dos teores de carboidratos foi de 5, 8 por cento. Callisthene apresentou o mais baixo teor de proteínas (16, 9 por cento), enquanto Q. cordata foi a espécie com o mais elevado teor (30 por cento em média). Teores de carboidratos solúveis em etanol foram muito superiores aos solúveis em água. Os teores de óleo foram superiores a 20 por cento na maioria das espécies (30, 4 por cento em V. pygmaea e V. pyramidalis). Ácidos graxos predominantes foram láurico (Q. grandiflora), oleico (Qualea e Salvertia) ou ácidos com cadeias mais longas (Salvertia e um grupo de espécies de Vochysia). A distribuição de ácidos graxos de Vochysiaceae sugere para as sementes de algumas espécies o uso em alimentação (predominância de ácido oléico), para outras, uma alternativa à manteiga de cacau (teores elevadosde ácido esteárico) ou produção de lubrificantes, tensoativos, detergentes, cosméticos e plásticos (predominância de ácidoscom cadeias C20 ou C22) ou biodiesel (predominância de ácidos monoinsaturados). Discute-se a possibilidade de aproveitamento de produtos de Vochysiaceae em regime de cultivo eem reservas extrativas.

Brazilian red propolis: unreported substances, antioxidant and antimicrobial activities.

BACKGROUND: Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Antimicrobial and antioxidant activities were also obtained. RESULTS: The propolis sample contained low content of narigenin-8-C-hexoside, this being the first report of a C-glycoside in propolis. The main constituent found was characterized as 3,4,2',3'-tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)-vestitol, (3S)-7-O-methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans-anethol, methyl eugenol, elimicin, methoxyeugenol and cis-asarone, and the triterpenic alcohols lupeol and α- and ß- amyrins. The methanol extract exhibited high antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl and ß-carotene/linoleic acid assay methods, and antimicrobial activity toward Gram-positive and Gram-negative bacteria. CONCLUSION: Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2',3'-tetrahydroxychalcone and a flavone C-glycoside in a propolis sample.

Hydroxycinnamic acid amide derivatives, phenolic compounds and antioxidant activities of extracts of pollen samples from Southeast Brazil.

Seven bee pollen samples (C1-C7) with different palynological sources were harvested from Pindamonhangaba municipality (Southeast Brazil). Methanol extracts of untreated samples (control), samples frozen at -18 °C and samples frozen and then dried were analyzed by HPLC/PAD/ESI/MS/MS. Flavonoid diglycosides of quercetin, kaempferol, isorhamnetin and patuletin were detected, together with hydroxycinnamic acid amide derivatives, such as N',N'',N'''-tris-p-feruloylspermidine and N',N'',N'''-tris-p-coumaroylspermidine. Distinct phenolic profiles characterized the analyzed samples, but no differences were noted as resulting from different treatments. Total phenolic contents determined with the Folin-Ciocalteau reagent ranged from 1.7 to 2.2%. Antioxidant activities above 75%, based on the DPPH method, were observed for all extracts, not correlated with total phenolic contents. Among samples from the same origin, those frozen were more active than samples untreated (control), and the samples frozen and then dried were the most active.