Biological properties of volatile oil from Brazilian brown propolis

ABSTRACT Propolis, is a bee product collected from exudates and flower buds of several plants, has strong aroma and several biological applications. This study aimed at evaluating the chemical composition and in vitro antioxidant, antibacterial and cytotoxic properties of volatile oil from Brazilian brown propolis. It was extracted by hydrodistillation and analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. Volatile oil from brown propolis exhibited strong antibacterial activity against H. pylori (MIC 3.25 µg/ml), Mycobacterium tuberculosis (MIC 50 µg/ml) and M. avium (MIC 62.5 µg/ml). It was evaluated in vitro for antioxidant activity by DPPH (IC50 25.0 µg/ml) and ABTS (IC50 30.1 µg/ml) methods. Its cytotoxic property was evaluated in normal (human fibroblasts, GM07429A) and tumor (MCF-7-human breast adenocarcinoma; HeLa-human cervical adenocarcinoma and M059J-human glioblastoma) cell lines. IC50 values were 81.32 µg/ml for GM07429A and 85.00, 129.40 and 84.12 µg/ml for MCF-7, HeLa and M059J cells, respectively. Three major dereplicated components of volatile oil from brown propolis were acetophenone (15.2%), nerolidol (13.3%), and spathulenol (11.6%). Our results contribute to a better understanding of the chemical and biological properties of Brazilian brown propolis and provide evidence for its potential medicinal use.

Eugenia Klotzschiana O. Berg Fruits as New Sources of Nutrients: Determination of their Bioactive Compounds, Antioxidant Activity and Chemical Composition

Abstract: The Cerrado is one of the world's biodiversity hotspots and Brazil's second largest biome. Many native species of the Brazilian Cerrado provide fruits that have unique sensory characteristics and high nutritional value. This study aimed at characterizing the pulp of Eugenia klotzschiana O. Berg, concerning its proximal composition, bioactive compound content and antioxidant activity. The pulp under study had high moisture (89.47 g kg-1) and caloric (96.07 kcal kg-1) values whereas its contents of protein (0.59 g kg-1) and lipids (2.35 g kg-1) were low. The cerrado pear pulp also had high iron content (16.5 mg kg -1) and dietary fiber (6.45 g kg-1), besides 0.034-0,055 mg kg-1 carotenoids, 8.66 mg kg-1 ascorbic acid and 0.66 mg kg-1 total chlorophyll. Total phenolic compounds (333.41-566.33 mg EAG kg-1) and flavonoids (225-50 mg EQ kg-1) were found by extraction methods named Method 1 (water) and Method 2 (acetone+methanol), respectively. Thus, the cerrado pear can be an alternative to improving nutrient intake and to providing sustainable use of the native flora in the Cerrado.

Harvest time on the content and chemical composition of essential oil from leaves of guava / Horário de coleta sobre o teor e a composição química do óleo essencial das folhas de goiabeira

ABSTRACT: The essential oil plants contents can be affected by several factors. For example, in certain plants, collection time has been observed to affect the content and chemical composition of the essential oil obtained from the plant. The objective of this study was to evaluate the effect of collection time on the content and chemical composition of the essential oil from guava ( Psidium guajava L.) leaves. Leaves were collected at different times of the day and the content and chemical composition of their essential oil was determined. Collection time did not qualitatively affect the chemical composition of the essential oil. However, concentration of certain substances in the oil, such as α-humulene and trans-caryophyllene, did significantly vary at different collection times. The main constituents of the essential oil of Psidium guajava are limonene (2.2-4.4%), trans-caryophyllene (18.1-17.1%), α-humulene (26.3-20.4%), aromadendrene (7.6-12.2%), α-selinene (7.3-11.3%), caryophyllene oxide (3.7-3.3%), humulene epoxide II (4.1-1.9%), and selin-11-en-4α-ol (7.2-11.1%). Leaves collected at 7:00 AM had higher essential oil production, with a content of 0.38% (d.b.), whereas leaves collected at 7:00 PM had lower essential oil production, 0.24% (d.b.). Chemical analysis showed that sesquiterpene compounds represented the highest concentration (62.0%), and monoterpenoids and monoterpenes represented the lowest concentrations (1.1 and 2.2%, respectively). Chemical classes that underwent major changes with respect to collection time were monoterpenes, sesquiterpenes, and sesquiterpenoids (2.2-4.4%, 63.8-61.7%, and 15.9-13.2%, respectively).

RESUMO: Existem fatores que podem afetar o conteúdo de óleo essencial das plantas, sendo o horário de coleta um deles. Assim, observa-se que o teor e a composição química de óleo essencial podem variar em certas plantas de acordo com horário de coleta. O objetivo deste trabalho foi avaliar o efeito do horário de coleta sobre o conteúdo e a composição química do óleo essencial das folhas de goiabeira ( Psidium guajava ). Folhas de Psidium guajava foram coletadas em diferentes horários do dia para determinar teor e composição química de seu óleo essencial. O óleo essencial não apresentou variação qualitativa da composição química em relação ao horário de coleta das folhas de Psidium guajava , mas alterou a concentração das substâncias, entre elas o α-humuleno e o trans-cariofileno. Os constituintes principais do óleo essencial das folhas de Psidium guajava são o limoneno (2,2-4,4%), trans-cariofileno (18,1-17,1%), α-humuleno (26,3-20,4%), aromadendreno (7,6-12,2%), α-selineno (7,3-11,3%), óxido de cariofileno (3,7-3,3%) epóxido de humuleno II (4,1-1,9%) e o selin-11-en-4α-ol (7,2-11,1%). No entanto, a maior produção de óleo essencial, foi obtida com as folhas coletadas às 19h, apresentando conteúdo de 0,38% (b.s.) e a mais baixa produção às 07h, apresentando conteúdo de 0,24% (b.s.). Através da análise química, identificou-se que compostos sesquiterpênicos apresentaram uma maior concentração (62,0%) e os monoterpenos e monoterpenoides foram os que apresentaram menor concentração (2,2 e 1,1%, respectivamente). As classes que sofreram maiores mudanças em relação ao horário de coleta foram os monoterpenos (2,2-4,4%) e os sesquiterpenos e os sesquiterpenoides (63,8-61,7% e 15,9-13,2%, respectivamente).

Chemical composition of the volatile oil of Cardiopetalum calophyllum collected in the Cerrado area / Composição química do óleo volátil de Cardiopetalum calophyllum coletada em área de Cerrado

ABSTRACT: The Annonaceae family consists of ~135 genera with diverse species and a large number of chemical compounds arising from the secondary metabolism. However, the chemical composition of the essential oil of several species of the family such as Cardiopetalum calophyllum has not been completely determined. In this study, the essential oils extracted from the leaves, flowers, and fruits of C. calophyllum, collected in typical areas of the Cerrado of Goiás, were characterized. The essential oil was extracted by hydrodistillation for 4h using a Clevenger apparatus. The chemical analysis was carried out by gas chromatography-mass spectrometry (GC-MS), and the constituents were identified by comparing the spectra and retention index obtained with those available in the literature. Twenty three compounds were identified in the essential oil of leaves; the oxygenated sesquiterpene, spathulenol (28.78%), was the major compound. Twenty five compounds were identified in the flowers, mainly comprising sesquiterpene hydrocarbons, germacrene-D (37.03%) and germacrene-B (13.72%). Seventeen compounds were reported in fruits, mainly comprising sesquiterpene hydrocarbons, germacrene-D (28.19%) and germacrene-B (20.90%), and an oxygenated sesquiterpene, spathulenol (11.53%). This is the first report on the chemical composition of the essential oils from leaves, flowers, and fruits of C. calophyllum.

RESUMO: A família Annonaceae é constituída por cerca de 135 gêneros, com uma diversidade extensa de espécies com grande quantidade de compostos químicos diversificados, advindos do metabolismo secundário. Entretanto, as informações sobre a composição química de óleo essencial de várias espécies da família ainda são incipientes, como é o caso da Cardiopetalum calophyllum. O trabalho teve como objetivo caracterizar quimicamente o óleo essencial extraído de folhas, flores e frutos da C. calophyllum, coletadas em áreas típicas do Cerrado goiano. A extração do óleo essencial se deu pelo método de hidrodestilação em aparelho de clevenger por um período de 4 horas. A análise química do óleo essencial foi realizada por cromatografia gasosa acoplada à espectrometria de massas (CG-MS) e a identificação dos constituintes pela comparação dos espectros obtidos com os espectros disponíveis na literatura e pelo cálculo do índice de retenção (IR). Foram identificados 23 compostos no óleo essencial das folhas, em que o composto majoritário foi o sesquiterpeno oxigenado espatulenol (28,78%); nas flores, foram identificados 31 compostos com predominância dos sesquiterpenos hidrocarbonados germacreno-D (37,03%) e germacreno-B (13,72%); e, nos frutos, 17 compostos com predominância dos sesquiterpenos hidrocarbonados germareno-D (28,19%) e germacreno-B (20,90%) e do sesquiterpeno oxigenado espatulenol (11,53%). Este trabalho descreve pela primeira vez a composição química do óleo essencial das folhas, flores e frutos da C. calophyllum, contribuindo significativamente para o conhecimento químico da espécie.