Ademir José Petenate

Bio: Ademir José Petenate is an academic researcher from State University of Campinas. The author has contributed to research in topics: Supercritical fluid extraction & Extraction (chemistry). The author has an hindex of 16, co-authored 35 publications receiving 1187 citations. Previous affiliations of Ademir José Petenate include University of North Carolina at Chapel Hill.

Extraction of ginger (Zingiber officinale Roscoe) oleoresin with CO2 and co-solvents: a study of the antioxidant action of the extracts

Abstract: The effects of temperature, pressure and the addition of co-solvent (ethanol (EtOH) and isopropyl alcohol (IsoC3), both at 1.17% (mass)) on the kinetics of extraction of ginger oleoresin were studied. The design used was a 2×2×3 factorial (pressure 200 and 250 bar; temperature: 25 and 35 °C; solvent: CO2, CO2+EtOH, CO2+IsoC3). The experimental setup used was a fixed bed extractor with diameter of 2.76×10−2 m and length of 0.387 m. The assays were carried out at a mean solvent flow rate of 5.86×10−5 kg/s and with a bed apparent density of 350 kg/m3. The identification of the substances present in the oleoresin was performed by GC-MS; GC-FID was used to determine the ginger extract compositions. The antioxidant activity of the extract fractions was determined using the coupled oxidation of linolenic acid and β-carotene. The results show that the temperature and the interaction of the pressure and the solvent significantly affected the total yield. For the mass transfer rate, the effect of the interaction of the pressure and the solvent was significant; the mass transfer rate increased with the pressure in the absence of the co-solvent and decreased when ethanol and isopropyl alcohol were used. The major substances present in the ginger extracts were α-zingiberene, gingerols and shogaols; the amounts of these compounds were significantly affected by temperature, pressure and solvent. Nonetheless, the antioxidant activity of the ginger extracts remained constant at ≈80% and decreased to ≈60% in the absence of gingerols and shogaols. The Sovova's model quantitatively described the overall extraction curves.

Supercritical fluid extraction of black pepper (Piper nigrun L.) essential oil

Abstract: Fixed bed extraction of black pepper essential oil using supercritical carbon dioxide as a solvent was studied. Composition of the extracted oil was obtained by chromatographic analysis, and solubility of the oil was determined using the dynamic method of extraction. Experiments were conducted at 30°C, 40°C and 50°C and 150, 200 and 300 bar. Solubility varied from 0.09 to 0.15 g oil/g CO 2 and increased with the solvent density. In the extraction curves (mass of oil versus mass of CO 2 ) it was possible to identify the constant extraction rate period as well as the failing and diffusion rate periods. About 70% of the total oil was extracted during the constant rate period.

Extraction of curcuminoids from deflavored turmeric (Curcuma longa L.) using pressurized liquids: Process integration and economic evaluation

Abstract: Pressurized liquid extraction (PLE) of curcuminoids from deflavored turmeric rhizomes was optimized. The rhizomes were initially deflavored by extraction with supercritical CO2. Immediately after SFE, PLE process was performed using ethanol as the solvent and a static extraction time of 20 min, and the independent variables were the temperature (333–353 K) and pressure (10–35 MPa). The results indicate that the optimum extraction temperature and pressure were 333 K and 10 MPa, respectively. PLE required three and six times less extraction time than low-pressure solvent extraction and Soxhlet extraction, respectively, to produce similar extraction yields. The cost of manufacturing (COM) decreased from US$ 94.92 kg−1 to US$ 88.26 kg−1 when the capacity of the two-extractor system increased from 0.05 m3 to 0.5 m3 and from US$ 94.92 kg−1 to US$ 17.86 kg−1 when the cost of the raw materials decreased from US$ 7.91 kg−1 to US$ 0.85 kg−1 for a two 0.05 m3 extractor system.

Supercritical fluid extraction and fractionation of natural matter

Abstract: Supercritical extraction and fractionation of natural matter is one of the early and most studied applications in the field of supercritical fluids In the last 10 years, studies on the extraction of classical compounds like essential and seed oils from various sources: seeds, fruits, leaves, flowers, rhizomes, etc, with or without the addition of a co-solvent have been published Supercritical extraction of antioxidants, pharmaceuticals, colouring matters, and pesticides has also been studied The separation of liquid mixtures and the antisolvent extraction are other processes that can perform very interesting separations Mathematical modelling has also been developed and refined for some of these processes The objective of this review is to critically analyze traditional and new directions in the research on natural matter separation by supercritical fluids extraction and fractionation

Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects

Abstract: Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity.