Optimization of Extraction Conditions and Characterization of Volatile Organic Compounds of Eugenia klotzschiana O. Berg Fruit Pulp.

Eugenia klotzschiana O. Berg is a native species to the Cerrado biome with significant nutritional value. However, its volatile organic compounds (VOCs) chemical profile is not reported in the scientific literature. VOCs are low molecular weight chemical compounds capable of conferring aroma to fruit, constituting quality markers, and participating in the maintenance and preservation of fruit species. This work studied and determined the best conditions for extraction and analysis of VOCs from the pulp of Eugenia klotzschiana O. Berg fruit and identified and characterized its aroma. Headspace solid-phase microextraction (HS-SPME) was employed using different fiber sorbents: DVB/CAR/PDMS, PDMS/DVB, and PA. Gas chromatography and mass spectrometry (GC-MS) were employed to separate, detect, and identify VOCs. Variables of time and temperature of extraction and sample weight distinctly influenced the extraction of volatiles for each fiber. PDMS/DVB was the most efficient, followed by PA and CAR/PDMS/DVB. Thirty-eight compounds that comprise the aroma were identified among sesquiterpenes (56.4%) and monoterpenes (30.8%), such as α-fenchene, guaiol, globulol, α-muurolene, γ-himachalene, α-pinene, γ-elemene, and patchoulene.

Chemical composition and inhibitory activities on dipeptidyl peptidase IV and pancreatic lipase of two underutilized species from the Brazilian Savannah: Oxalis cordata A.St.-Hil. and Xylopia aromatica (Lam.) Mart.

Brazil has the greatest vegetal biodiversity in the world, but products derived from native species are not optimally utilized. Oxalis cordata and Xylopia aromatica are two underutilized species whose leaves and fruits, respectively, have been used as food in the 19th century. In this study, we used chemical and in vitro assays to evaluate the potential of these species as functional foods. The inhibitory activity on pancreatic lipase and DPP-IV were evaluated using the crude extracts and fractions ethyl acetate, butanol and water of these two species. For polyphenols determination, samples were prepared with different solvents and these were analysed by chromatographic and spectroscopic methods. Finally, fatty acids profile was determinated by gas chromatography. The crude extract (IC50=0.84mg/ml), ethyl acetate extract (IC50=0.88mg/ml) an aqueous fraction (IC50=0.63mg/ml) of C. cordata were inhibitory on pancreatic lipase but inactive against dipeptidyl peptidase IV (DPP-IV). Extracts from X. aromatica were inactive against the lipase pancreatic enzyme, but a butanolic fraction inhibited DPP-IV (IC50=0.71±0.05mg/ml). The phenolic acids orientin/isorientin, chlorogenic acid (0.32g/100g) and the flavonoid derivatives rutin (0.27g/100g), quercetin and luteolin were observed in all products. Additionally, fatty acid quantification showed that oleic (7.5g/100g) and linoleic acid (6.5g/100g) were predominant in X. aromatica fruit. This study confirms the potential for the use of both plants as functional foods due to their nutritional value, biological activity and important phytochemical content.