Ferulic acid as major antioxidant phenolic compound of the Tetragonisca angustula honey collected in Vera Cruz - Itaparica Island, Bahia, Brazil

Abstract The antioxidant activity of Tetragonisca angustula honey (TAH) and its ethanolic extract (TAEE) were investigated. The total levels of phenolic (TPC) and flavonoids (TFC) were also evaluated. The results for TPC were 19.91 ± 0.38 and 29.37 ± 1.82 mg GAE g-1 and for TFC 0.20 ± 0.02 and 0.14 ± 0.01 mg QE g-1 of TAH and TAEE, respectively. Antioxidant activities were 73.29 ± 0.49% and 93.36 ± 0.27% in the DPPH assay and 71.73 ± 4.07% and 97.86 ± 0.35% in ABTS+ for TAH and TAEE, respectively. The total reducing activity was determined by the method of reducing power (PR) and iron ion (Fe III) and the results varied in PR from 151.7 ± 25.7 and 230.7 ± 25.2 mg GAE L-1, for TAH and TAEE respectively and for (Fe III) in EC50 0.284 in TAEE and 0.687 in TAH. Chemical analysis by HPLC-DAD of the ethanolic extract (TAEE) revealed the presence of ferulic acid as majority phenolic component in the extract. The 1H NMR analysis confirmed this structure and showed the also presence of glucose, citric acid, succinic acid, proline and hydrocarbon derivatives. In addition, the botanical origin was also investigated and showed a multifloral characteristic, having found 19 pollen types with a botanical predominance of the Anacardiaceae family, with Tapirira pollen occurring as predominant (42.6%) and Schinus as secondary (25.7%). The results showed that T. angustula honey is an interesting source of antioxidant phenolic compounds due to its floral origin and can act as a protector of human health when consumed.

Resumo A atividade antioxidante do mel de Tetragonisca angustula (TAH) e seu extrato etanólico (TAEE) foram investigados. Os níveis totais de fenólicos (TPC) e flavonóides (TFC) também foram avaliados. Os resultados para TPC foram 19,91 ± 0,38 e 29,37 ± 1,82 mg GAE g-1 e para TFC 0,20 ± 0,02 e 0,14 ± 0,01 mg QE g-1 de TAH e TAEE, respectivamente. As atividades antioxidantes foram 73,29 ± 0,49% e 93,36 ± 0,27% no ensaio DPPH e 71,73 ± 4,07% e 97,86 ± 0,35% no ABTS+ para TAH e TAEE, respectivamente. A atividade redutora total foi determinada pelo método de poder redutor (PR) e íon ferrico (Fe III) e os resultados variaram em PR de 151,7 ± 25,7 e 230,7 ± 25,2 mg GAE L-1, para TAH e TAEE respectivamente e para (Fe III) em EC50 0,284 em TAEE e 0,687 em TAH. A análise química por HPLC-DAD do extrato etanólico (TAEE) revelou a presença de ácido ferúlico como componente majoritário no extrato. A análise de RMN 1H confirmou esta estrutura e mostrou a presença de glicose, ácido cítrico, ácido succínico, prolina e derivados de hidrocarbonetos no TAEE. Além disso, a origem botânica também foi investigada e apresentou característica multifloral, tendo encontrado 19 tipos polínicos com predomínio botânico da família Anacardiaceae, sendo o pólen Tapirira predominante (42,6%) e o Schinus secundário (25,7%). Os resultados mostraram que o mel de T. angustula é uma interessante fonte de compostos fenólicos antioxidantes devido à sua origem floral e pode atuar como protetor da saúde humana quando consumido.

Ferulic acid as major antioxidant phenolic compound of the Tetragonisca angustula honey collected in Vera Cruz - Itaparica Island, Bahia, Brazil / Ácido ferúlico como principal composto fenólico antioxidante do mel de Tetragonisca angustula coletado em Vera Cruz - Ilha de Itaparica, Bahia, Brasil

Abstract The antioxidant activity of Tetragonisca angustula honey (TAH) and its ethanolic extract (TAEE) were investigated. The total levels of phenolic (TPC) and flavonoids (TFC) were also evaluated. The results for TPC were 19.91 ± 0.38 and 29.37 ± 1.82 mg GAE g-1 and for TFC 0.20 ± 0.02 and 0.14 ± 0.01 mg QE g-1 of TAH and TAEE, respectively. Antioxidant activities were 73.29 ± 0.49% and 93.36 ± 0.27% in the DPPH● assay and 71.73 ± 4.07% and 97.86 ± 0.35% in ABTS●+ for TAH and TAEE, respectively. The total reducing activity was determined by the method of reducing power (PR) and iron ion (Fe III) and the results varied in PR from 151.7 ± 25.7 and 230.7 ± 25.2 mg GAE L-1, for TAH and TAEE respectively and for (Fe III) in EC50 0.284 in TAEE and 0.687 in TAH. Chemical analysis by HPLC-DAD of the ethanolic extract (TAEE) revealed the presence of ferulic acid as majority phenolic component in the extract. The 1H NMR analysis confirmed this structure and showed the also presence of glucose, citric acid, succinic acid, proline and hydrocarbon derivatives. In addition, the botanical origin was also investigated and showed a multifloral characteristic, having found 19 pollen types with a botanical predominance of the Anacardiaceae family, with Tapirira pollen occurring as predominant (42.6%) and Schinus as secondary (25.7%). The results showed that T. angustula honey is an interesting source of antioxidant phenolic compounds due to its floral origin and can act as a protector of human health when consumed.

Resumo A atividade antioxidante do mel de Tetragonisca angustula (TAH) e seu extrato etanólico (TAEE) foram investigados. Os níveis totais de fenólicos (TPC) e flavonóides (TFC) também foram avaliados. Os resultados para TPC foram 19,91 ± 0,38 e 29,37 ± 1,82 mg GAE g-1 e para TFC 0,20 ± 0,02 e 0,14 ± 0,01 mg QE g-1 de TAH e TAEE, respectivamente. As atividades antioxidantes foram 73,29 ± 0,49% e 93,36 ± 0,27% no ensaio DPPH● e 71,73 ± 4,07% e 97,86 ± 0,35% no ABTS●+ para TAH e TAEE, respectivamente. A atividade redutora total foi determinada pelo método de poder redutor (PR) e íon ferrico (Fe III) e os resultados variaram em PR de 151,7 ± 25,7 e 230,7 ± 25,2 mg GAE L-1, para TAH e TAEE respectivamente e para (Fe III) em EC50 0,284 em TAEE e 0,687 em TAH. A análise química por HPLC-DAD do extrato etanólico (TAEE) revelou a presença de ácido ferúlico como componente majoritário no extrato. A análise de RMN 1H confirmou esta estrutura e mostrou a presença de glicose, ácido cítrico, ácido succínico, prolina e derivados de hidrocarbonetos no TAEE. Além disso, a origem botânica também foi investigada e apresentou característica multifloral, tendo encontrado 19 tipos polínicos com predomínio botânico da família Anacardiaceae, sendo o pólen Tapirira predominante (42,6%) e o Schinus secundário (25,7%). Os resultados mostraram que o mel de T. angustula é uma interessante fonte de compostos fenólicos antioxidantes devido à sua origem floral e pode atuar como protetor da saúde humana quando consumido.

The characteristics of stingless bee nests (Apidae: Meliponini) in the Cycloop Mountain Nature Reserve, Indonesia

Introduction: Stingless bees are widespread in tropical and subtropical regions. In Indonesia, the distribution of stingless bees are grouped in three regions, namely Indo-Malayan, Wallacea, and Indo-Australian. Ten species of stingless bees have been recorded in Papua, seven of which are endemic. The Cycloop Mountains Nature Reserve (CMNR) is one of the conservation area in Papua, Indonesia, for flora and fauna. Unfortunately, the study of the diversity of stingless bees in Papua has been limited. Objective: To measure the diversity, nesting sites, nest entrance characteristics and nest architecture of stingless bees. Methods: Observation of the stingless bee nests in the nature reserves and in the residential areas used a road sampling method and information from local people, respectively. A total of 22 colonies were studied. Results: Two species of stingless bee were found, namely Tetragonula sapiens (Cockerell, 1911) and Heterotrigona (Platytrigona) planifrons (Smith, 1865). The current study showed new distribution records for T. sapiens and H. planifrons in the CMNR. The nesting site of T. sapiens was commonly found in house foundation, while that of H. planifrons was in coconut palm cavities. The nest entrance of T. sapiens varied, i.e., elliptical, oval, rounded, irregular, horizontally or vertically elongated. Meanwhile, the nest entrance of H. planifrons was vertically elongated. The brood cells of T. sapiens varied, i.e., vertical, horizontal, or semi-clusters, while in H. planifrons was layered vertically. Conclusions: Two species of stingless bees found, T. sapiens and H. planifrons, showed a new distribution records and T. sapiens was a dominant species in Papua. The nest entrance of the species varied in shape, color, and texture.

Introducción: Las abejas sin aguijón están muy extendidas en las regiones tropicales y subtropicales. En Indonesia, la distribución de las abejas sin aguijón se agrupa en tres regiones: Indo-Malayan, Wallacea e Indo-Australian. Se han registrado diez especies de abejas sin aguijón en Papua, siete de las cuales son endémicas. La Reserva Natural de las Montañas Cycloop (CMNR) es una de las áreas para la conservación de flora y la fauna en Papua, Indonesia. Desafortunadamente, el estudio de la diversidad de abejas sin aguijón en Papua ha sido limitado. Objetivo: Medir la diversidad, los sitios de anidación y describir la arquitectura y características de entrada al nido de las abejas sin aguijón. Métodos: Se observaron los nidos de abejas sin aguijón en reservas naturales y áreas residenciales, mediante el método de muestreo de caminos e información de la población local, respectivamente. Se estudiaron 22 colonias. Resultados: Se encontraron dos especies de abejas sin aguijón, Tetragonula sapiens (Cockerell, 1911) y Heterotrigona (Platytrigona) planifrons (Smith, 1865). Este estudio mostró nuevos registros de distribución de T. sapiens y H. planifrons en el CMNR. El sitio de anidación de T. sapiens se encontró comúnmente en los cimientos de las casas, mientras que el de H. planifrons estaba en las cavidades de las palmas de coco. La forma de la entrada al nido de T. sapiens varió: elíptica, ovalada, redondeada, irregular, alargada horizontal o verticalmente. Mientras tanto, la entrada al de H. planifrons se alarga verticalmente. Las celdas de cría de T. sapiens variaron, entre verticales, horizontales o semi-racimos, mientras que en H. planifrons eran verticales. Conclusiones: Se encontraron dos especies de abejas sin aguijón, T. sapiens y H. planifrons, que mostraron nuevos registros de distribución y T. sapiens fue una especie dominante en Papúa. La entrada al nido de las especies varió en forma, color y textura.

In Vitro Investigation of Antioxidant and Antidiabetic Properties of Phenolic-Rich Extract from Stingless Bee Honey (Heterotrigona itama)

@#Introduction: The increase of Type 2 diabetes mellitus has prompted numerous research toward finding an alternative to manage the disease through the oxidant-antioxidant balance, mainly through bioactive compounds in natural products. This study explored the antioxidant and antidiabetic properties of phenolic-rich extract (PRE) from Stingless bee honey (SBH) (Heterotrigona itama) as therapeutic agent to restore the redox balance. Methods: The total phenolic content (TPC), total flavonoid content (TFC) and antioxidant assays of PRE and SBH, were determined to provide preliminary insight into the sample’s antioxidant properties, followed by high-performance liquid chromatography analysis of PRE. The antidiabetic potential of PRE and SBH were determined based on their inhibition against α-amylase and α-glucosidase enzymes. The cytotoxicity analysis of PRE was conducted on 3T3-L1 adipocytes and L6 muscle cells before the glucose uptake and cellular antioxidant analyses were performed on both cell lines, respectively. Results: PRE yielded higher TPC, TFC and antioxidant activities than SBH. The phytochemical profile of PRE comprises gallic acid, myricetin, kaempferol, epicatechin, chlorogenic acid, quercetin, syringic acid, and cinnamic acid. The results from carbohydrate enzymatic inhibitory assays collectively suggested that PRE exhibited more robust antidiabetic activities than SBH. PRE showed good glucose uptake stimulating and reactive oxygen species scavenging effects in those cell lines. Conclusion: Overall, PRE from SBH showed higher carbohydrate enzymatic inhibition, glucose uptake, and protection against intracellular oxidative stress, primarily due to its high antioxidant content and may serve as an alternative therapeutic agent for managing T2DM.

Effect of symbiotic bee fungus on survival of stingless bee Heterotrigona itama larvae

Aims@#Symbiotic bee fungus associated with the stingless bee larval food has been revealed to play a major role in performing a mutual relationship with the host. The fungus is believed capable to produce crucial nutrients that are required for larval pupation. However, detailed information on the fungus identification isolated from the larval food of our native Indo-Malaya stingless bee, Heterotrigona itama (Hymenoptera: Apidae), is poorly understood. Hence, this study was conducted to determine the effect of fungus isolated from the stingless bee larval food on the survival of H. itama larvae and identify the isolated fungus using both morphological and molecular analyses.@*Methodology and results@#Elisa plates designed with F-bottom type were used as artificial brood cells in a controlled condition. The eggs transferred to Elisa plates were kept in the incubator with 75%-100% humidity and 25 ± 2.5 °C of temperature. This study carried out in three different treatments: (1) microbes-free larval food, (2) fresh larval food and (3) microbes-free larval food with fungus supplement. Results showed that the survival of H. itama larvae depends on the presence of beneficial fungus with the highest survival rate (Treatment 2 = 85.71%). The absence of the beneficial fungus in the fluid food of H. itama showed the lowest survival rate (Treatment 1 = 37.14%). Microscopy analysis showed that the fungus had various forms, including unconjugated asci, round-shaped ascospore and pseudohyphae. The molecular characterisation of the isolated fungi was performed using 23S rRNA gene sequencing using universal primers ITS1 and ITS4. DNA barcoding of three isolated fungi confirmed all isolated fungi matched Panus lecomtei (Basidiomycetes; Poriales; Polyporaceae) with 99.70% of similarity.@*Conclusion, significance and impact of study@#This study provides information on the importance of whitish fungus in appearance that existed in the brood cell, which is proposed to be the crucial component of in-vitro stingless bee queen rearing protocol.

Stingless bee propolis, metformin, and their combination alleviate diabetic cardiomyopathy

Abstract Background and aim: Stingless bee propolis, a resinous compound processed by mandibular secretion of stingless bees, is used for maintenance of hygiene and stability of beehives. Research on stingless bee propolis shows therapeutic properties attributed to polyphenols exhibiting antioxidative, antihyperglycemic and antiischemic effect. However, the cardioprotective effect of stingless bee propolis on diabetic cardiomyopathy is unknown. Methods: Adult male Sprague Dawley rats were randomised to five groups: normal group, diabetic group, diabetic given metformin (DM+M), diabetic given propolis (DM+P) and diabetic given combination therapy (DM+M+P) and treated for four weeks. Body weight, fasting blood glucose, food and water intake were taken weekly. At the end of experiment, biomarkers of oxidative damage were measured in serum and heart tissue. Antioxidants in heart tissue were quantified. Part of left ventricle of heart was processed for histological staining including Haematoxylin and Eosin (H&E) stain for myocyte size and Masson's Trichrome (MT) stain for heart fibrosis and perivascular fibrosis. Results: Propolis alleviated features of diabetic cardiomyopathy such as myocyte hypertrophy, heart fibrosis and perivascular fibrosis associated with improvement in antioxidative status. Conclusion: This study reports beneficial effect of propolis and combination with metformin in alleviating histopathological feature of diabetic cardiomyopathy by modulating antioxidants, making propolis an emerging complementary therapy.

Efficiency of two digestion methods in determining the presence of metals (Cd, Cu, Cr, Pb and Zn) in geopropolis produced by Melipona scutellaris / Eficacia de dos métodos de digestión para determinar metales (Cd, Cu, Cr, Pb y Zn) en geopropóleos producidos por Melipona scutellaris / Eficiência de dois métodos de digestão para determinar metais (Cd, Cu, Cr, Pb e Zn) na geoprópolis produzida por Melipona scutellaris

Abstract This study evaluates the efficiency of acid extraction and total digestion to determine the presence of metals in geopropolis produced by the stingless bee Melipona scutellaris. Geopropolis samples were collected at five meliponaries in the city and in the metropolitan region of Salvador, Bahia State, Brazil. The sample treatment methods comprised acid extraction and total digestion. The Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) technique was used to quantify Cd, Cu, Cr, Pb, and Zn. Geopropolis samples submitted to both digestion methods showed statistical differences. For both methods, Cr and Zn showed the highest concentrations, while those of Cd were the lowest. The Cr concentration for determination by total digestion was 37.53 mg/kg, while for acid extraction it was 32.90 mg/kg. For Zn, the concentration was 17.65 mg/kg and 8.85 mg/kg for total digestion and acid extraction, respectively. The total digestion method showed the highest concentrations of the metals evaluated; however, acid extraction (USEPA 3050b) is a more straightforward procedure for metal evaluation in geopropolis samples and presented values that support the use of geopropolis as a bioindicator. The acid extraction method USEPA 3050b, in combination with detection using ICP OES, showed efficiency in analyses carried out to determine metals in geopropolis.

Resumen El objetivo de este artículo fue evaluar la eficacia da extracción ácida y de la digestión total para determinación de metales absorbidos en geopropóleos producidos por Melipona scutellaris. Se colectaron muestras de geopropóleos en cinco meliponarios localizadas en la región metropolitana del Salvador, estado de Bahia, Brasil. Se utilizaron como métodos de tratamiento para muestras, la extracción ácida y la digestión total. Para determinar los metales Cd, Cu, Cr, Pb y Zn se utilizó Espectroscopia de Emisión Óptica con Plasma Acoplado Inductivamente (ICP OES). Se encontraron diferencias estadísticas en la concentración de metales hallados en las muestras de geopropóleos sometidas a los diferentes métodos de digestión. Para ambos métodos de digestión, las mayores concentraciones de metal fueron observadas para Cr y Zn. Entre los metales evaluados Cd presentó la menor concentración. La concentración de Cr para la determinación por digestión total fue de 37,53 mg/kg y para la extracción ácida fue de 32,90 mg/ kg. Para el Zn, la concentración fue de 17,65 mg/kg y 8,85 mg/kg para la digestión total y la extracción ácida, respectivamente. El método de digestión total mostró los mayores valores para concentraciones de los metales evaluados. Entretanto, la extracción ácida, USEPA 3050b, es un procedimiento más simple para la evaluación de metales en muestras de geopropóleos y también mostró valores que pueden satisfacer la necesidad de su uso en evaluaciones de colmenas como bio-indicador. El método de extracción ácida USEPA 3050b en combinación con la detección a través de ICP OES se mostró eficiente para el análisis de metales en geopropóleos.

Resumo O objetivo deste estudo foi avaliar a eficiência da extração ácida e da digestão total para determinação de metais adsorvidos na geoprópolis produzida por Melipona scutellaris. Foram coletadas amostras de geoprópolis em cinco meliponários, situados em Salvador, Estado da Bahia e região metropolitana. Foram utilizados como métodos de tratamento das amostras a extração ácida e a digestão total. Para determinação dos metais Cd, Cu, Cr, Pb e Zn utilizou-se a Espectrometria de Emissão Óptica com Plasma Indutivamente Acoplado (ICP OES). Houve diferença estatística na concentração de metais encontrados nas amostras de geoprópolis submetidas aos diferentes métodos de digestão. Para ambos os métodos de digestão as maiores concentrações de metais foi observada para o Cr e Zn. Dentre os metais avaliados o Cd apresentou a menor concentração. A concentração de Cr para determinação por digestão total foi de 37,53 mg/kg e para extração ácida de 32,90 mg/ kg. Para o Zn, a concentração foi de 17,65 mg/kg e 8,85 mg/kg para digestão total e extração ácida, respectivamente. O método de digestão total apresentou os maiores valores para concentrações dos metais avaliados. No entanto, a extração ácida, USEPA 3050b, é um procedimento mais simples para a avaliação dos metais em amostras de geoprópolis e também apresentou valores que podem satisfazer a necessidade de utilização na avaliação deste produto da colmeia como bioindicador. O método de extração ácida USEPA 3050b em combinação com a detecção por ICP OES mostrou eficiência para análise de metais em geoprópolis.

Determination of phenolic profile by HPLC-ESI-MS/MS, antioxidant activity, in vitro cytotoxicity and anti-herpetic activity of propolis from the Brazilian native bee Melipona quadrifasciata

ABSTRACT Propolis is a rich source of bioactive molecules made by bees by collecting an infinite variety of secondary metabolites from plants. This study determined the chromatographic and mass spectrometry profile along with the biological activity of propolis produced by the native Brazilian bee Melipona quadrifasciata. A hydroalcoholic crude extract was prepared and partitioned in solvents of different polarities, generating aqueous, dichloromethane, ethyl acetate, butanol and insoluble fractions. The phenolic and flavonoid content was also determined in crude aqueous and methanolic extracts as well. The antioxidant activity was determined by three different methods and correlated with the phenolic and flavonoid content. Extracts and fractions were tested against the herpes simplex virus type 1, and the cytotoxicity was evaluated in fibroblast L929 cells. The chromatographic and mass spectrometry analysis revealed the presence of catechin, epicatechin, aromadendrin, naringenin, pinocembrin and p-coumaric acid. The methanolic extract, ethyl acetate fraction and insoluble fraction possess higher phenolic and flavonoid content along with better antioxidant activities. The ethyl acetate and butanol fractions, along with the FM14 and FM45 subfractions demonstrated better viral inhibition, with 50% inhibitory concentrations of 90.5, 294, 188 and 58.5 µg ml−1, respectively. Among these, the ones presenting the best selectivity index were the ethyl acetate and FM45 fractions, with a pronounced virucidal effect. The methanolic extract stood out in the antioxidant activities and showed no cytotoxicity bellow 125 µg ml−1, exhibiting the most promising biological activity. Although this propolis seems to act in the early stages of herpetic infections, it is still difficult to correlate this activity with a single constituent of this complex mixture, suggesting a synergism in the extract components. To our knowledge, this is the first study of its kind with this propolis type.

Brazilian stingless bee propolis and geopropolis: promising sources of biologically active compounds

ABSTRACT Stingless bee products such as honey, pollen, propolis, and geopropolis have been used for centuries in traditional medicine for the treatment of several illnesses. Investigation of the biological activity of stingless bee products, especially propolis and geopropolis, has revealed promising therapeutic properties. About 20% of total Neotropical stingless bees can be found in Brazil. Despite the species diversity, studies on their biological activity are scarce. The present review focuses on the antioxidant and antimicrobial activities of propolis and geopropolis from Brazilian stingless bees. In addition, the toxicity of these natural products was addressed. In order to provide new evidences for the toxic potential of propolis and geopropolis components, an in silico analysis was performed using the ADMET PredictorTM software. We observed that most of studies evaluated only crude ethanol extracts of a limited number of stingless bees species. Propolis and geopropolis displayed antioxidant capacity and antimicrobial activity. Concerning the toxic potential, the extracts of stingless bees propolis and geopropolis were considered safe. Nonetheless, in vitro and in vivo toxicological studies are still necessary.

Partial characterization of ethanolic extract of Melipona beecheii propolis and in vitro evaluation of its antifungal activity

ABSTRACT The ethanolic extract of Melipona beecheii Bennett 1831, propolis from Yucatán Mexico was evaluated in vitro for the determination of its phenolic compound content, antioxidant capacity and antifungal activity. The results were compared against those of the ethanolic extract of Apis mellifera propolis. The total phenolic content, flavonoid content and flavanones-dihydroflavonols content were assessed by colorimetric methods. The antifungal activity was assessed in vitro against Candida albicans. For the ethanolic extract of M. beecheii propolis; total phenolic content, was 263.25 ± 8.78 µg/ml, total flavonoid content was 768 ± 204 µg/ml and flavanones-dihydroflavonols content was 335.42 ± 15.08 µg/ml. For antioxidant activity assessed as DPPH scavenging and iron reducing power ethanolic extract of M. beecheii propolis reported IC50 of 32.47 and 1.60 µg/ml of gallic acid equivalent respectively. Regarding antifungal activity against C. albicans, the minimal inhibitory concentration and minimal fungicidal concentration for ethanolic extract of M. beecheii propolis were 1.62 ± 0.33 and 2.50 ± 0.22 µg/ml of dry extract; For both minimal inhibitory concentration and minimal fungicidal concentration, ethanolic extract of M. beecheii propolis required 30% less concentration of dry extract than ethanol extract of A. mellifera propolis to exert the same antifungal actions against C. albicans. To the best of our knowledge, this is the first report about the flavonoid and flavanones-dihydroflavonols content of M. beecheii propolis. Due to the lack of information available about the stingless bee's honeycomb products, the study and conservation of endemic honeybees should remain as an active focus of research.

Pentacyclic triterpenes and other constituents in propolis extract from Melipona beecheii collected in Yucatan, México

ABSTRACT Thirteen pentacyclic triterpenes, methyl 3-oxours-12-en-23-oate, marsformosanone, taraxerone, β-amyrenone, α-amyrenone, lupenone, 24-methylencycloartan-3-one, moretenol acetate, β-amyrin acetate, germanicol acetate, 24-methylencycloartanyl acetate, β-amyrin, and α-amyrin were identified in a chloroform-methanol propolis extract from Melipona beecheii. Additionally, were identified in this propolis, hexadecanoic acid, methyl ester, octadecanoic acid, methyl ester and 1-triacontanol. The purification of the propolis extract was carried out using different chromatographic techniques, including vacuum liquid chromatography, gravity column chromatography and gel filtration chromatography Sephadex LH-20. The identification of the metabolites was performed using mass spectrometry.

Development and validation of a high-performance thin layer chromatography method for the simultaneous quantitation of α- and γ-mangostins in Thai stingless bee propolis

ABSTRACT Stingless bees (Apoidea) are widely distributed and commercially cultivated in artificial hives in fruit gardens. Their propolis are commonly used in traditional medicine to treat various diseases (e.g., abscesses, inflammations, and toothaches) and as a constituent of numerous health products. Thus, this study aimed to (i) develop and validate a high-performance thin layer chromatography method for the quantitation of major active constituents (α- and γ-mangostins) in propolis produced by five stingless bee species (Tetragonula fuscobalteata Cameron, T. laeviceps Smith, T. pagdeni Schwarz, Lepidotrigona terminata Smith, and L. ventralis Smith) cultivated in Thai mangosteen orchards and (ii) determine an optimal extraction solvent. Separation was performed on a silica gel 60 F254 plate using toluene/ethyl acetate/formic acid (8:2:0.1, v/v/v) as a mobile phase, and the developed method was validated to assure its linearity, precision, accuracy, and limits of detection/quantitation. Propolis extract from T. fuscobalteata exhibited the highest mangostin content, and acetone was shown to be more a more effective extraction solvent than dichloromethane, ethanol, or methanol. Thus, the simplicity and reliability of the developed method make it well suited for the routine analysis (e.g., for quality control) of commercial products containing stingless bee propolis.

Active phloem sap collection by Trigona spinipes (Fabricius) (Hymenoptera, Apidae)in Artemisia annuaLinn (Asteraceae)

Trigona spinipes Fabricius (Apidae: Meliponini), is a common stingless bee widely seen in urban and rural areas in Brazil, popularly known as irapuá, arapuá or bee-dog. Although these bees are considered pollinators of some cultivated plants, they are better known for the damage they cause in different crops. During experimental agroecological cultivation of Artemisia (Artemisia annuaLinn, Asteraceae), in Jaguariúna (SP, Brazil), stingless bees Trigona spinipes (Fabricius) were observed sucking phloem sap directly from the plant, a phenomenon not yet described in scientific literature. This study aimed to register and describe the phloem sap-sucking behavior performed by T. spinipesfor the first time, as well as to assess the potential impact of this behavior on A. annuacultivation. The behavior and the material collected by bees and the severity of attack were also analyzed. The aging and premature death of observed A. annuaspecimens occurred because of extensive lesions caused by T. spinipes, confirming the negative consequence of sap-sucking attacks of T. spinipesbees on the plants. Factors that could induce this unusual behavior were presented, pointing out the need for future studies on the development of strategies to protect plants, without causing damage to the T. spinipesbee populations, which are elements of Brazilian bee fauna and, therefore, protected by law.

Antioxidant Properties of Stingless Bee Honey and Its Effect on the Viability of Lymphoblastoid Cell Line

@#Research on the medical benefit of stingless bee honey (kelulut honey) is rather new although it has been used as traditional food and additive for ages. The primary 92 Med & Health Jun 2019;14(1): 91-105 Hazirah H. et al. objective of our study was to evaluate the antioxidant properties of kelulut honey and its effect on lymphoblastoid cell line. We analysed the antioxidant properties of kelulut honey by ferric reducing antioxidant potential assay, total phenolic and flavonoid contents using UV spectrophotometry. The total phenolic content, total flavonoid content and ferric reducing antioxidant potential of Malaysian kelulut honey produced by Trigona spp. were found to be 844.45 mg RE/kg honey, 78.29 mg RE/kg honey and 1132.66 mM FE/kg honey, respectively. Our findings showed a strong correlation between total phenolics and flavanoids contents with its antioxidant potential at R2 = 0.920 and R2 = 0.951, respectively. The effect of honey on cell viability of lymphoblastoid cell line (LCL) was also investigated. The cells were cultured in RPMI-1640 medium supplemented with 0 - 500 μg/mL of kelulut honey for 24 hours. Cell viability was quantitated using 3-(4,5-dimethylthiazol2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, MTS assay showed that honey supplementation boosted the viability of LCL up to 164.64% (p< 0.01). The significant increase in cell viability might be modulated by the antioxidant properties of kelulut honey.

Comparison of Sugar Content, Mineral Elements and Antioxidant Properties of Heterotrigona Itama Honey from Suburban and Forest in Malaysia

@#Introduction: In Malaysia, Heterotrigona itama sp. (stingless bee) industries start to grow rapidly since 2015 but the study on its health benefit is still lacking. This study was aimed to analyse and compare the sugar content, minerals and antioxidant properties of stingless bee honey collected from forest and suburban area in Malaysia. Methods: Sugar content was determined by HPLC, minerals and heavy metals was determined by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and Atomic Absorption Spectrometer (AAS), total phenolic content (TPC) and total flavonoid content (TFC) by Folin-Ciocalteu and aluminium chloride colorimetry method, respectively. For determining the antioxidant activity of the samples, 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH), 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assay were used. Results: Fructose, glucose and sucrose are found in all samples in range of 16.03-33.13 g/100g, 8.63-20.72 g/100g and 2.68-34.04 g/100g, respectively. Potassium and sodium were major minerals in all stingless bee honey with an average of 622.36 and 496.01 mg/kg, respectively. Sample from the forest (Sibu, F2) has the highest TPC and TFC with value 520.663±8.119µg GAE/g and 443.25±18.194µg RE/g, respectively. The higher antioxidant activities (DPPH, ABTS, FRAP) also found in samples collected from the forest (F2) with 602.15±12.7 µg TE/g, 575.18±9.38 µg TE/g and 641.36±42.11µg TE/g, respectively. Conclusion: All stingless bee honey studied shown a significant amount of important minerals and antioxidant properties with samples from forest clearly shown significantly higher TPC and TFC as well as the antioxidant activity than samples collected from the suburban area.

Anti-Cancer Properties of Heterotrigona itama sp. Honey Via Induction of Apoptosis in Malignant Glioma Cells

@#Background: There has been increasing evidence showing that stingless bee honey exhibits anti-oxidant, anti-inflammatory and anti-cancer properties. Pharmacologically-active components in honey such as flavonoids and phenolic constituents are known to contribute to its medicinal benefits. To the best of our knowledge, this is the first study on evaluating anticancer effects of locally-produced Malaysian stingless bee honey from Heterotrigona itama sp. on malignant glioma cells. Methods: Proliferation and apoptosis studies of U-87 MG cells following stingless bee honey treatment were carried out using MTS assay and acridine orange/propidium iodide dual staining, respectively. Results: Results demonstrated time and dose-dependent cytotoxicity using 0.625%, 1.25% and 10% stingless bee honey (P < 0.05). IC50 values were calculated using cells treated with 10% stingless bee honey. It was also observed that 10% stingless bee honey induced nuclear shrinkage, chromatin condensation and nucleus fragmentation, indicating that cellular changes were consistent with the apoptotic characteristics of the cells. Conclusion: These data provide a good basis for further evaluation of the medicinal properties of stingless bee honey from Heterotrigona itama sp. This source of honey may serve as a potential therapy for malignant glioma.

Physicochemical Characteristics of Malaysian Stingless Bee Honey from Trigona Species

The physicochemical properties of stingless bee honey are diverse according to origin of geographical orbotanical and fruit or flower season. These factors result in production of honey with different colour, pH,ash and water content although the bee species is similar. To date, the physicochemical properties ofhoney from Malaysian Trigona species are unknown. Therefore, determination of physicochemicalproperties of honey from stingless bee is crucial for Malaysian researchers in order to analyse the purity ofthe honey. Five honey samples were used for the current study. Four samples were stingless bee honeyfrom two of the most common domesticated Malaysian stingless bee species; Trigona thorasica and Trigonaitama. Meanwhile, one sample was from Tualang honey. For stingless bee honey, the values for pH,moisture content, electrical conductivity, ash content and hydroxymethylfurfural (HMF) were 2.79±0.04 to2.95±0.02, 28.3±0.68 to 33.7±0.51, 0.47±0.22 to 0.55±0.38, 0.132±0.03 to 0.532±0.83 and 0.080±0.16 to3.42±1.03, respectively. The colour of stingless bee honey varies based on observation or absorbanceassay. The study described the physicochemical properties derived from Malaysian bees of Trigonathorasica, Trigona itama, and Api

Microbiological quality of honey from stingless bee, jandaíra (Melipona subnitida), from the semiarid region of Brazil / Qualidade microbiológica do mel da abelha sem ferrão jandaíra (Melipona subnitida) da região semi-árida do Brasil

ABSTRACT: The aim of this study was to evaluate the presence of microorganisms in honey produced by the stingless bee (SB) jandaíra (Melipona subnitida) from the semiarid region of Brazil. Thirty-five samples were analyzed and all of them were positive for mesophilic bacteria, coliforms at 45°C, fungi, and yeast. Staphylococcus spp. were identified in 85.7%, while Bacillus spp. were detected in 34.3% of honey samples. DNAs of Clostridium perfringens and C. botulinum were detected in 40% and 2.8% of the samples, respectively. Salmonella spp. and C. difficile were not detected. The present research revealed a great diversity of microorganisms in honey produced by jandaíra.

RESUMO: O objetivo deste trabalho foi avaliar a presença de microrganismos no mel produzido pela abelha sem ferrão jandaíra (Melipona subnitida). Trinta e cinco amostras foram avaliadas e todas foram positivas para bactérias mesofílicas, coliformes a 45 ºC, fungos e leveduras. Staphylococcus spp. foi identificado em 85,7% enquanto Bacillus foi detectado em 34,3% das amostras de mel. Clostridium perfringens e C. botulinum foram detectados em 40% e 2,8% das amostras respectivamente. Salmonella spp. e C. difficile não foram detectados. O presente trabalho revelou uma grande diversidade de microrganismos no mel produzido por jandaíra.

Development of antennal sensilla of Tetragonisca angustula Latreille, 1811 (Hymenoptera: Meliponini) during pupation / Desenvolvimento das sensilas antenais de Tetragonisca angustula latreille, 1811 (Hymenoptera: Meliponini) durante a pupação

Abstract The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.

Resumo As sensilas antenais são órgãos sensoriais formados por um conjunto de neurônios que captam estímulos ambientais e células acessórias, desempenhando as funções de mecanorreceptores e quimiorrecepterores. Este trabalho descreve o desenvolvimento pós-embrionário das sensilas antenais de operárias das abelhas sem ferrão Tetragonisca angustula (Hymenoptera: Meliponini). O desenvolvimento das sensilas tem início na transição de pré-pupa para pupa de olho branco e estão completamente desenvolvidas no estágio de pupa de olho preto, mas ainda estão cobertas pela cutícula velha. As sensilas estão completamente expostas em operárias recém-emergidas de T. angustula, mas é possível que estímulos ambientais sejam percebidos em estágios anteriores devido aos poros presentes na cutícula velha.

Palinologia e a interação planta-abelha: Revisão de literatura / Palynology and plant-bee interaction: Literature review / Palinología y la interacción planta y abeja: Revisión de literatura

A Palinologia é responsável pelo estudo do pólen de angiospermas, esporos de pteridófitas e de fungos, cistos de algas, dinoflagelados, foraminíferos acritarcas e partículas de carvão. Três hipóteses embasam as análises palinológicas: (1) a chuva polínica vigente reflete a vegetação presente na área em estudo; (2) o acúmulo e a conservação dos palinomorfos não prejudicam a personificação da chuva polínica; e (3) a amostragem, o processamento químico, a contagem e a identificação dos palinomorfos reconstituem fielmente a chuva polínica da área. A aplicação da Palinologia nos diversos ramos da ciência torna-se viável graças à imensa variabilidade morfológica presente no pólen (ou nos palinomorfos), o que possibilita definir famílias, gêneros e espécies botânicas. As relações entre abelhas e plantas podem ser feitas por meio da análise do pólen transportado pelas fêmeas ou daquele armazenado em células de cria ou em potes de alimento. A interação entre abelhas e plantas está relacionada ao processo de polinização, responsável pela renovação da flora de vários ecossistemas.(AU)

Palynology is responsible for the study of angiosperms pollen, pteridophyte and fungal spores, algae cysts, dinoflagellates, actinic foraminifera and charcoal particles. Three hypotheses support palynological analyzes: (1) the pollen rain reflects the vegetation present in the study area; (2) the accumulation and conservation of palynomorphs do not impair the personification of pollen rain; and (3) the sampling, chemical processing, counting, and identification of palynomorphs faithfully reconstitute the pollen rain area. The application of palynology in the various branches of science becomes feasible due to the immense morphological variability present in pollen (or palynomorphs), which makes it possible to define families, genera and botanical species. The relationships between bees and plants can be made through the analysis of pollen carried by the female animals or stored in the breeding cells or food pots. The interaction between bees and plants is related to the pollination process, responsible for the renewal of the flora of several ecosystems.(AU)

La Palinología es responsable por el estudio del polen de angiospermas, esporos de pteridofitas y de hongos, quistes de algas, dinoflagelados, foraminíferos, acritarcas y partículas de carbón. Tres hipótesis embazan los análisis palinológicos: (1) la lluvia polínica vigente refleja la vegetación presente en el área en estudio; (2) el acúmulo y la conservación de los palinomorfos no perjudican la personificación de la lluvia polínica; y (3) el muestreo, el procesamiento químico, el conteo y la identificación de los palinomorfos reconstituyen fielmente la lluvia polínica del área. La aplicación de la Palinología en los diversos seguimientos de la ciencia se hace viable gracias a la inmensa variabilidad morfológica presente en el polen (o en los palinomorfos), lo que posibilita definir familias, géneros y especies botánicas. Las relaciones ente abejas y plantas pueden ser hechas a través del análisis del polen transportado por las hembras o de aquel almacenado en células de cría o en potes de alimentos. La interacción entre abejas y plantas está relacionada al proceso de polinización, responsable por la renovación de la flora de varios ecosistemas.(AU)