Pressurized liquid extraction of flavanols and alkaloids from cocoa bean shell using ethanol as solvent.

Cocoa shell (CS) is a co-product of the cocoa industry used mainly as fuel for boilers but with secondary applications as fertilizer and in animal feed. Although it is known that this material is rich in flavanols and alkaloids, to date, a study has not been conducted that has quantitatively identified these compounds in CS. Thus, the aim of this work was to characterize CS in terms of its composition, regarding catechin, epicatechin, procyanidin B2, caffeine and theobromine, and to evaluate the extraction kinetics of the total flavanols using pressurized liquid extraction (PLE) with absolute ethanol. For the determination of the extraction kinetic data, the DMAC method was used, while each compound was quantified using a UPLC-MS/MS analysis. The major compounds found were theobromine and epicatechin (mean values of 9.89 and 3.5 mg/g CS, respectively). PLE proved to be quite effective; the flavanols extraction yield was enhanced by increasing the temperature and extraction time however, high extraction times and temperatures degraded the procyanidins B2. Peleg's model applied to extraction data description provided a reasonable agreement with the experimental results, which allows their application in modeling and optimization of solid-liquid extraction of the total flavanols from cocoa bean shell.

Isolation by pressurised fluid extraction (PFE) and identification using CPC and HPLC/ESI/MS of phenolic compounds from Brazilian cherry seeds (Eugenia uniflora L.).

Brazilian cherry seeds are a waste product from juice and frozen pulp production and, the seeds composition was investigated to valorize this by-product. Compounds separation was performed with ethanol by pressurised fluid extraction (PFE). Here we determine the effect of temperature (T), static time (ST), number of cycles (C), and flush volume (VF) on the yield, composition and total phenolic content (TPC) of the seed extracts. T, ST and their interaction positively influenced yield and TPC. Extracts were fractionated by high performance liquid chromatography (HPLC) and centrifugal partition chromatography (CPC). The collected fractions characterizations were made by electrospray ionisation mass spectrometry (ESI/MS) and high resolution mass spectrometry (HRMS) indicated the presence of ellagic acid pentoside and deoxyhexose, quercitrin and kaempferol pentoside. All of these compounds have antioxidant properties and normally are found in plant extracts. These results confirm that Brazilian cherry seed extract is a potentially valuable source of antioxidants.