Antioxidative and Immunomodulatory Potential of the Endemic French Guiana Wild Cocoa “Guiana”

Abstract

Guiana is a little-known and endemic variety of cocoa (Theobroma cacao), native to French Guiana. No data were available regarding its chemical composition and biological properties; therefore, a study was necessary, using Forastero as a reference. To exemplify biological activities of the cacao species, cocoa extracts were evaluated by antioxidant (DPPH, FRAP, ORAC) and anti-inflammatory assays. Our results showed that raw Guiana presented equivalent DPPH and FRAP activities, but a 1.3-fold higher antioxidant activity (1097 ± 111.8 μM ET/g DM) than Forastero (838.5 ± 67.8 μM ET/g DM) in ORAC assay. Furthermore, the impact of fermentation (under four conditions: unfermented, two days, four days and six days of fermentation) on Guiana cocoa beans composition and health properties was also studied. Indeed, fermentation, a key step necessary to obtain the taste and color of chocolate, is generally known to alter bean composition and modulate its health benefits. At six days, the fermentation process led to a nearly 25% lower antioxidative capacity in various assays. Moreover, in inflammation-induced macrophage assays, Guiana and Forastero unfermented extracts induced a 112% stimulation in TNF-α production, and a 56.8% inhibition of IL-6 production. Fermentation altered the cocoa composition by diminishing bioactive compounds, which could be responsible for these biological activities. Indeed, after six days of fermentation, compounds decreased from 614.1 ± 39.3 to 332.3 ± 29 mg/100 g DM for epicatechin, from 254.1 ± 14.8 to 129.5 ± 20.7 mg/100 g DM for procyanidin B2 and from 178.4 ± 23.5 to 81.7 ± 2.9 mg/100 g DM for procyanidin C1. The similar composition and the equivalent or higher antioxidant activity of Guiana leads us to propose it as an alternative to Forastero.

Theobroma cacao and Theobroma grandiflorum: Botany, Composition and Pharmacological Activities of Pods and Seeds

“…An approximative total polyphenol content (TPC) using the Folin-Ciocalteu method showed that COPs had lower TPC than COBs: 3.2 ± 0.3–56.5 ± 0.6 mg gallic acid equivalent/g of DW) [ 46 , 69 , 77 , 78 ]) vs. 9.8 ± 0.1–202.2 ± 6.5 mg GAE/g of DW [ 75 , 79 , 80 ]. Polyphenol contents may vary according to various parameters such as genotype [ 81 , 82 ], maturity [ 83 ], soil, and crop conditions (sun exposure, number of fruits on tree, soil type) [ 82 , 84 ].…”

Benefits of Polyphenols and Methylxanthines from Cocoa Beans on Dietary Metabolic Disorders

“…To determine the fraction of polyphenols in cocoa, several analytic methods are applied, such as the following: Colorimetric/Spectrophotometric (UV-Vis) methods [ 4 , 45 , 46 , 47 , 48 , 49 , 50 ]: Total polyphenol content by the Folin–Ciocalteu method Total anthocyanidins content by the analysis of pH variation Total flavonoids content by AlCl 3 method Total proanthocyanidins by Vanillin, DMACA, butanol-HCl or bovine serum albumin (BSA) methods Chromatographic methods [ 51 , 52 ]: Thin layer chromatography High performance liquid chromatography (Identification with or without mass spectrometry detector/Determination of the polymerization degree of tannin by thiolysis such as phloroglucinolysis) …”

“…Colorimetric/Spectrophotometric (UV-Vis) methods [ 4 , 45 , 46 , 47 , 48 , 49 , 50 ]: Total polyphenol content by the Folin–Ciocalteu method Total anthocyanidins content by the analysis of pH variation Total flavonoids content by AlCl 3 method Total proanthocyanidins by Vanillin, DMACA, butanol-HCl or bovine serum albumin (BSA) methods …”

“…This is believed to be due to increased early insulin secretion and the activity of the glucagon-like peptide-1(GLP-1) activity [ 104 ]. These antidiabetic actions would not be visible for all cocoa polyphenols because only the catechin cocoa fraction showed an enhancement in glucose-stimulated insulin secretion, whereas treatments with crude cocoa extract or procyanidin fraction showed no improvement [ 4 ].…”

“…To become one of the most widely consumed products in the world, namely chocolate, cocoa seeds must undergo several processes such as fermentation, drying and roasting [ 2 ]. Consumed for its flavor, raw cocoa and cocoa-derived products revealed human health benefits as protective against cardiovascular and neurodegenerative diseases, antioxidant and anti-inflammatory activities [ 3 , 4 ]. Bioactive compounds, particularly polyphenols and methylxanthines, are thought to be responsible for these properties [ 5 , 6 ].…”