Stability of total phenolic concentration and antioxidant capacity of extracts from pomegranate co-products subjected to in vitro digestion
| dc.contributor.author | Fawole, Olaniyi Amos | en_ZA |
| dc.contributor.author | Opara, Umezuruike Linus | en_ZA |
| dc.date.accessioned | 2016-09-15T12:43:08Z | |
| dc.date.available | 2016-09-15T12:43:08Z | |
| dc.date.issued | 2016-09 | |
| dc.description | CITATION: Fawole, O. A. & Opara, U. L. 2016. Stability of total phenolic concentration and antioxidant capacity of extracts from pomegranate co-products subjected to in vitro digestion. BMC Complementary and Alternative Medicine, 16:358, doi:10.1186/s12906-016-1343-2. | |
| dc.description | The original publication is available at http://bmcmusculoskeletdisord.biomedcentral.com | |
| dc.description | Publication of this article was funded by the Stellenbosch University Open Access Fund. | |
| dc.description.abstract | Background: Co-products obtained from pomegranate juice processing contain high levels of polyphenols with potential high added values. From value-addition viewpoint, the aim of this study was to evaluate the stability of polyphenolic concentrations in pomegranate fruit co-products in different solvent extracts and assess the effect on the total antioxidant capacity using the FRAP, DPPH˙ and ABTS+ assays during simulated in vitro digestion. Methods: Pomegranate juice, marc and peel were extracted in water, 50 % ethanol (50%EtOH) and absolute ethanol (100%EtOH) and analysed for total phenolic concentration (TPC), total flavonoids concentration (TFC) and total antioxidant capacity in DPPH˙, ABTS+ and FRAP assays before and after in vitro digestion. Results: Total phenolic concentration (TPC) and total flavonoid concentration (TFC) were in the order of peel > marc > juice throughout the in vitro digestion irrespective of the extraction solvents used. However, 50 % ethanol extracted 1.1 to 12-fold more polyphenols than water and ethanol solvents depending on co-products. TPC and TFC increased significantly in gastric digests. In contrast, after the duodenal phase of in vitro digestion, polyphenolic concentrations decreased significantly (p < 0.05) compared to those obtained in gastric digests. Undigested samples and gastric digests showed strong and positive relationships between polyphenols and the antioxidant activities measured in DPPH, ABTS+ and FRAP assays, with correlation coefficients (r2) ranging between 0.930–0.990. In addition, the relationships between polyphenols (TPC and TFC) and radical cation scavenging activity in ABTS+ were moderately positive in duodenal digests. Conclusion: Findings from this study showed that concentration of pomegranate polyphenols and the antioxidant capacity during in vitro gastro-intestinal digestion may not reflect the pre-digested phenolic concentration. Thus, this study highlights the need to provide biologically relevant information on antioxidants by providing data reflecting their stability and activity after in vitro digestion. | en_ZA |
| dc.description.uri | http://bmccomplementalternmed.biomedcentral.com/articles/10.1186/s12906-016-1343-2 | |
| dc.description.version | Publisher's version | |
| dc.format.extent | 10 pages : illustrations | en_ZA |
| dc.identifier.citation | Fawole, O. A. & Opara, U. L. 2016. Stability of total phenolic concentration and antioxidant capacity of extracts from pomegranate co-products subjected to in vitro digestion. BMC Complementary and Alternative Medicine, 16:358, doi:10.1186/s12906-016-1343-2 | |
| dc.identifier.issn | 1472-6882 (online) | |
| dc.identifier.other | doi:10.1186/s12906-016-1343-2 | |
| dc.identifier.uri | http://hdl.handle.net/10019.1/99658 | |
| dc.language.iso | en_ZA | en_ZA |
| dc.publisher | BioMed Central | |
| dc.rights.holder | Authors retain copyright | |
| dc.subject | By-product | en_ZA |
| dc.subject | DPPH | en_ZA |
| dc.subject | Polyphenols | en_ZA |
| dc.subject | Pomegranate | en_ZA |
| dc.subject | Value-addition | en_ZA |
| dc.title | Stability of total phenolic concentration and antioxidant capacity of extracts from pomegranate co-products subjected to in vitro digestion | en_ZA |
| dc.type | Article | en_ZA |