•Extraction of pequi pulp oil using subcritical propane.•Influence of operating conditions was investigated on the extraction of pequi pulp oil.•Design of experiments was carried out with response ...surface methodology.•Fatty acid composition of the pequi pulp oil.
Brazil is rich in oil plants that have natural antioxidants in their constitution, among which “pequi” (Caryocar coriaceum) stands out, a fruit represented by several species and the most common in the Northeastern Brazilian states such as Ceará and Pernambuco. This fruit has a lot of oil which can be used for nutritional and medicinal purposes. The aim of this research was to study the oil extraction process from pequi pulp, the quality of the extracts, kinetic modeling, and extraction with subcritical propane. Pequi fruits were extracted and their pulps were dried and ground. The oil extracted with subcritical propane was obtained at a pressure range of 5–15MPa and temperatures of 303.15–333.15K. The highest yield was 43.69% for the extraction condition of 15MPa and 333.15K. Ethanol and ethyl acetate were used in concentrations of 10–25% (volume) as solvent modifiers to obtain yields up to 44.99%. Soxhlet extractions were performed using ethanol and hexane as solvents and higher yield (52.78%) was obtained with the use of ethanol. The fatty acid analysis showed that different experimental conditions did not impact the fatty acid profile. The fatty acids found at greater proportion were palmitic acid (35.4%, in mass) and oleic acid (60.6%, in mass). The phenolic compound content was determined by the Folin-Ciocalteu method and showed no significant difference among the extraction methods used. Different mass transfer models (Crank, Sovová, and Martinez models) reported in the literature were used to model the extraction curves. The Sovová model had the best fit to the experimental data.
•The re-use of chia seed cake as raw material to obtain bioactive extracts is a novelty.•Chia seed cake extracts presented the same quality that whole chia seeds extracts.•Chia seed cake extracts are ...rich in ω-3 and ω-6 fatty acids and phenolic compounds.•Biological and nutritional valuation of an agroindustrial waste were achieved.•SFE from chia seed cake is profitable and produces extracts with a competitive price.
Chia (Salvia hispanica) seed is a source of natural antioxidants and essential fatty acids. The present study evaluated the oil extraction from chia seed cake, a residue from chia seed oil extraction by cold pressing. Extraction conditions (pressure, temperature, solvent) and its effects in the quality of the extracts were studied. The re-use of an agroindustrial residue (chia seed cake) for obtaining extracts rich in bioactive compounds (high added value), mainly using the supercritical technology, is a novelty. Published studies on this subject have not been found. Supercritical fluid extraction (SFE) was performed at pressures from 150 to 300bar and temperatures of 40–50°C, using CO2 as solvent or CO2 added to ethanol (EtOH) or ethyl acetate (EtOAc) as cosolvents at 2.5–7.5% w/w of the total CO2 mass. Extracts obtained by SFE were compared to extracts obtained by low-pressure techniques (LPE), using hexane, EtOH, and EtOAc as solvents. All extracts were evaluated as antioxidant content (ABTS and DPPH methods), total phenolics content (TPC), fatty acids profile (GC-FID) and in vitro antimicrobial activity analysis. SFE assays using pure CO2 reached yields up to 10.6±0.2% at 300bar and 50°C. SFE with 7.5% of EtOH increased the process yield and TPC of the extract. LPE techniques using EtOH and EtOAc produced extracts with the best TPC values (50±3 and 79±2mg CAE/gextract, respectively) and EC50 values (760±19 and 621±11μg/mL, respectively). GC-FID confirmed the high content of linoleic and α-linolenic acids (∼80% together), and the presence of palmitic, stearic and oleic acids, in minor amounts for all of the extract samples evaluated. It was noted that chia seed cake extracts presented the same quality that whole chia seed extracts, studied by other authors. Extracts obtained by different techniques also showed weak antimicrobial activity against B. cereus. The economic evaluation indicated SFE of chia seed cake is a profitable way to reuse this agroindustrial waste.
Leaves and products made from them are the major focus of research on bioactive compounds of mate (
Ilex paraguariensis). However, studies on other parts of the plant, are scarce. The aim of this ...study was to determine the methylxanthines, phenolic compounds, and antioxidant activity of mate bark (residual biomass) and compare with those of mate leaves. The high antioxidant activity of mate bark and its high concentration of total polyphenols were apparent in both the aqueous and the methanolic extracts, the values of which were greater than those detected in the leaves. Of the phenolic acids identified, the levels of chlorogenic acid and 4,5-dicaffeoylquinic acid in the samples were significantly higher in the methanolic bark extract. With regard to methylxanthines, considerable concentrations were detected in the samples. The results obtained contribute to the viability of exploiting this residue, broadening the use of the mate plant.
Summary
This study evaluated the quality of oil extracted from yellowfin tuna (Thunnus albacares) by enzymatic hydrolysis (EHO) compared with oil extracted by traditional methods, such as the ...physical method of cooking and pressing after fishmeal production and the chemical solvent method. The oil extracted by EHO presented the lowest acidity (1.96% oleic acid) and peroxide indexes (5.14 mEq O2 kg−1 of oil) and the highest levels of eicosapentaenoic acid (6.05g 100 g−1) and docosahexaenoic acid (27.15 g 100 g−1), two omega‐3 fatty acids with high nutritional value. Importantly, oil extraction from yellowfin tuna heads using EHO produced oil rich in omega‐3s with no oxidation. This study shows that this extraction method greatly increases the value of fish by‐products and increases the competitiveness of the fishing industry.
Enzymatic extraction of oil from yellowfin tuna (Thunnus albacares) by‐products: a comparison with other extraction methods.
Ilex paraguariensis is known to contain compounds with antioxidant properties, such as phenolic acids, and its stimulant properties are attributed to methylxanthines, such as caffeine. The aims of ...this study were to evaluate the phenolic, methylxanthinic, and tannin composition of a mate residue (mate powder), to compare the quali-quantitative phenolic composition and the antioxidant potential of extracts obtained from distinct solvent systems. Among the extracts prepared with different solvents, the 80% methanol extract showed the highest total polyphenol content (11.51 g/100 g) and antioxidant activity. HPLC analysis showed that 4,5 dicaffeoylquinic acid is the major component of the phenolic fraction of mate powder. The caffeine, theobromine, and tannin contents in mate powder were 1.01, 0.10, and 0.29 g/100 g, respectively. Consumption of mate powder would significantly contribute to antioxidant and stimulant intake, providing high amounts of phenolic acids, tannins, and methylxanthines with biological effects potentially beneficial for human health. Practical Application: This article contributes to the minimization of residues in yerba-mate processing.
Aloysia gratissima (Gill. et Hook) Tronc. (Verbenaceae) is native to South America with folk therapeutic applications for a wide range of diseases. The polyphenolic and carotenoid profile, toxicity, ...and antioxidant activity of aqueous extract of Aloysia gratissima were investigated. HPLC analyses showed high amounts of ferulic acid, trans-cinnamic acid and p-coumaric acid, and also trans-β- carotene and lutein which fluctuated throughout the seasons. Furthermore, the extract investigated not only exerted antioxidant activity but also inhibited lipid peroxidation. Toxicity was achieved only at the highest dose tested. Therefore, A. gratissima is a potential species for medicinal purposes.
The aim of this work was to evaluate the chemical properties of the residues from erva-mate processing and also to determine the candy-making performance with addition of residues from erva-mate on ...consumers’ acceptance and purchase intent of this new product. The candies containing different amounts of mate powder were evaluated through overall acceptability test and purchase intent. Mate powder showed high contents of dietary fiber, total ash, and total polyphenols. The total dietary fiber content of the mate candies ranged from 5.7 to 6.29% on a dry matter basis. Supplementation with mate powder caused significant increases in polyphenol and mineral contents of mate candies. The incorporation of mate powder increased the hardness of the candies and produced desirable results in their nutritional characteristics. The sensory tests indicated that mate candies were acceptable and approved in relation to purchase intent.
The objective of this research was to evaluate the chemical composition, microstructure, and antioxidant capacity of king palm flour obtained from residues from organic king palm (
Archontophoenix ...alexandrae) processing. King palm flour exhibited high levels of dietary fibre (70.85%) and total ash (3.27%); low contents of protein (3.51%) and lipid (0.91%). Iron, magnesium, calcium and potassium contents were 7.31, 517.03, 801.33 and 1041.95
mg/100
g, respectively. The high concentration of glucose, xylose and arabinose suggests the presence of some polysaccharides, such as cellulose and hemicelluloses (xyloglucans and arabinoxylans). Methanol and aqueous extracts of king palm flour showed 1.27 and 0.95
mg/g (Gallic Acid Equivalents) of total polyphenols, respectively. Methanol extract yielded the best antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH
) and 2,2′-azino-di(3-ethylbenzthiazoline sulphonate) (ABTS
+) methods. The micrographs of leaf sheath showed the presence of druses, which are characterized as calcium oxalate deposition, contributing to the calcium content in king palm flour. The presence of primary and secondary cell walls lignified in leaf sheath contributed to high levels of dietary fibre detected in king palm flour.
The replacement of the blend of rice flour (70%) and corn starch (30%) with king palm flour Archontophoenix alexandrae (F. Muell.) H. Wendl. and Drude at levels of 0-30% was investigated for its ...effects on the chemical and physical characteristics of gluten-free dough and cookies. Cookies containing 10, 20 and 30% of king palm flour were analysed by twenty-one celiac consumers through preference-ranking test. Ash, minerals, and dietary fibre contents increased in cookies that were added with king palm flour. Compared with the control dough, the incorporation of king palm flour increased the firmness and decreased the adhesiveness of dough samples. The incorporation of king palm flour increased the hardness of cookies in relation to the control dough. None of the cookies differed significantly (P > 0.05) in the lightness (L*) parameter. All formulations produced cookies with hue angles around 60, which indicate a tendency to brown colour. The study reveals that the incorporation of king palm flour showed desirable results in nutritional characteristics, because of the increase of the dietary fibre and minerals contents. In this study, the cookies preferred by celiac consumers were those containing 10 and 20% of king palm flour (P > 0.05).
Resumen En América Latina se ha desarrollado, durante las últimas décadas, una serie de investigaciones que comienzan a desplazar el enfoque etnográfico tradicional y ponen en práctica nuevas ...metodologías de corte participativo. En este artículo expondré algunas de las críticas centrales que se han realizado al enfoque clásico y presentaré un modelo metodológico evocativo, fundado en la autoría nativa. Citaré también algunas de las investigaciones significativas en esta nueva línea (Lindenberg, 1993, 1996; Gasché, 2004; Podestá, 1997, 2002, 2003; Bertely, 2006) y discutiré los riesgos que se dan en trabajos de esta índole cuando ciertos principios, sobre todo los que se refieren a la postura del intelectual (formativa, política y ética), no son explicitados.
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