Rejane P. D. Silva

Chemical Composition and Biological Activity of Extracts Obtained by Supercritical Extraction and Ethanolic Extraction of Brown, Green and Red Propolis Derived from Different Geographic Regions in Brazil

The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection.

Determination of Parameters for the Supercritical Extraction of Antioxidant Compounds from Green Propolis Using Carbon Dioxide and Ethanol as Co-Solvent

The aim of this study was to determine the best processing conditions to extract Brazilian green propolis using a supercritical extraction technology. For this purpose, the influence of different parameters was evaluated such as S/F (solvent mass in relation to solute mass), percentage of co-solvent (1 and 2% ethanol), temperature (40 and 50°C) and pressure (250, 350 and 400 bar) using supercritical carbon dioxide. The Global Yield Isotherms (GYIs) were obtained through the evaluation of the yield, and the chemical composition of the extracts was also obtained in relation to the total phenolic compounds, flavonoids, antioxidant activity and 3,5-diprenyl-4-hydroxicinnamic acid (Artepillin C) and acid 4-hydroxycinnamic (p-coumaric acid). The best results were identified at 50°C, 350 bar, 1% ethanol (co-solvent) and S/F of 110. These conditions, a content of 8.93±0.01 and 0.40±0.05 g/100 g of Artepillin C and p-coumaric acid, respectively, were identified indicating the efficiency of the extraction process. Despite of low yield of the process, the extracts obtained had high contents of relevant compounds, proving the viability of the process to obtain green propolis extracts with important biological applications due to the extracts composition.

Antioxidant, antimicrobial, antiparasitic, and cytotoxic properties of various Brazilian propolis extracts.

Propolis is known for its biological properties and its preparations have been continuously investigated in an attempt to solve the problem of their standardization, an issue that limits the use of propolis in food and pharmaceutical industries. The aim of this study was to evaluate in vitro antioxidant, antimicrobial, antiparasitic, and cytotoxic effects of extracts of red, green, and brown propolis from different regions of Brazil, obtained by ethanolic and supercritical extraction methods. We found that propolis extracts obtained by both these methods showed concentration-dependent antioxidant activity. The extracts obtained by ethanolic extraction showed higher antioxidant activity than that shown by the extracts obtained by supercritical extraction. Ethanolic extracts of red propolis exhibited up to 98% of the maximum antioxidant activity at the highest extract concentration. Red propolis extracts obtained by ethanolic and supercritical methods showed the highest levels of antimicrobial activity against several bacteria. Most extracts demonstrated antimicrobial activity against Staphylococcus aureus. None of the extracts analyzed showed activity against Escherichia coli or Candida albicans. An inhibitory effect of all tested ethanolic extracts on the growth of Trypanosoma cruzi Y strain epimastigotes was observed in the first 24 h. However, after 96 h, a persistent inhibitory effect was detected only for red propolis samples. Only ethanolic extracts of red propolis samples R01Et.B2 and R02Et.B2 showed a cytotoxic effect against all four cancer cell lines tested (HL-60, HCT-116, OVCAR-8, and SF-295), indicating that red propolis extracts have great cytotoxic potential. The biological effects of ethanolic extracts of red propolis revealed in the present study suggest that red propolis can be a potential alternative therapeutic treatment against Chagas disease and some types of cancer, although high activity of red propolis in vitro needs to be confirmed by future in vivo investigations.

Use of Patent Indicators as a Methodology for Evaluating the Development of Supercritical Extraction Technology

The use of science and technology indicators that plan investments in research, development and innovation has been growing in recent years. This article aimed to evaluate the scientific and technological indicators, through research related to patent applications and spending on RD&I carried out by the sponsor countries of supercritical extraction technology. Survey was carried out in the online databases for European office Espacenet (EP), by collecting, processing and analysis of information extracted from patent documents. The researched technology is mainly concentrated in developed countries, which have the largest investments in RD&I in recent years.

Prospective Study on the Collection and Incorporation of Cellulose Nanocrystals in Biodegradable Films

In recent years, several research groups have reported new techniques for forming nanocelulose from different natural sources and for the incorporation of these polymeric materials. The objective of this work was to technological prospecting mapping process to obtain nanocrystals, main sources and implementing them in biodegradable films. It was observed that the United States stands out as the largest holder of technology of interest.

Effect of Applying Pectinolytic Enzymes in Spondias tuberosa Arr. Cam. Pulp

Umbu (Spondias tuberosa Arr. Cam.) is a native fruit from the Brazilian semi-arid regions of northeastern, which has been raising the attention of the exotic fruit sector due to its nutritional and sensorial qualities, increasing the range of products using umbu as raw material. With the aim to verify the effect of applying pectinolytic enzymes on colour and viscosity of umbu pulp, an central composite design with three independent variables (viscosity, L* and b*) and three dependent variables (viscosity, L* and b*) was applied using umbu pulp at three different pH values (2.3, 3.5 and 4.5). The most significant results were found with pH 2.3 for viscosity response, and pH 3.5 for L*. With the fruit s natural pH of 2.3 time and temperature were the most significant variables for viscosity. With pH 3.5 e zy ati o e tratio a d ti e ere the aria les that i flue ed the pulp s lu i osity, ithi the tested values. The application of these enzymes exerted effect on reducing viscosity and in the process of clarifying the umbu pulp. Therefore, it should be consider the pH ratio, temperature and enzyme concentration to define the technical parameters of industrial application to umbu fruit pulp.