Metabolomic and chemometric profiles of ten southern African indigenous fruits

Nompumelelo J Nkosi; Tinotenda Shoko; Vimbainashe E Manhivi; Retha M Slabbert; Yasmina Sultanbawa; Dharini Sivakumar

doi:10.1016/j.foodchem.2022.132244

Metabolomic and chemometric profiles of ten southern African indigenous fruits

Food Chem. 2022 Jul 1:381:132244. doi: 10.1016/j.foodchem.2022.132244. Epub 2022 Jan 29.

Authors

Nompumelelo J Nkosi¹, Tinotenda Shoko², Vimbainashe E Manhivi², Retha M Slabbert², Yasmina Sultanbawa³, Dharini Sivakumar⁴

Affiliations

¹ Phytochemical Food Network Research Group, Department of Crop Sciences, Tshwane University of Technology, Pretoria 0001, South Africa; Department of Horticulture, Tshwane University of Technology, Pretoria 0001, South Africa.
² Department of Horticulture, Tshwane University of Technology, Pretoria 0001, South Africa.
³ ARC Training Centre for Uniquely Australian Foods, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Kessels Rd, Coopers Plains, Queensland QLD 4108, Australia.
⁴ Department of Horticulture, Tshwane University of Technology, Pretoria 0001, South Africa; ARC Training Centre for Uniquely Australian Foods, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Kessels Rd, Coopers Plains, Queensland QLD 4108, Australia. Electronic address: SivakumarD@tut.ac.za.

PMID: 35184010
DOI: 10.1016/j.foodchem.2022.132244

Abstract

Using UPLC-QTOF/MS, metabolites were identified in 10 indigenous fruits from South Africa. Metabolomic-chemometric analysis showed chlorogenic acid scored highest for the discrimination of three different fruit clusters. Heat maps showed patterns and groupings based on the metabolite concentrations. The highest concentrations of quercetin 3-O-α-l-arabinopyranoside (401.09 mg/kg), delphinidin 3-galactoside (57.80 mg/kg), procyanidin B-type dimer (527.07 mg/kg) and epicatechin (1349.46 mg/kg), was in Englerophytum magalismontanum (Transvaal milkplum). Syzygium cordatum (Water berry) had the highest concentrations of quercetin 3-galactoside and methyl gallate 3-O-beta-d-glucopyranoside, Ficus capensis (Cape fig) the most 3-CQA and 5-CQA, and Parinari curatellifolia (Mobola plum) had the highest FRAP (9.5 mmol TEAC/g) and DPPH (14.2 IC₅₀ µg/mL) scavenging activities. When compared to eight other indigenous fruits, Ximenia caffra (Sour plum), and Landolphia kirkii (Sand apricot vine), showed the highest inhibition of carbohydrate hydrolysing enzymes. Correlation analysis identified candidates responsible for each biological activity in these fruits, proving their utility as functional ingredients.

Keywords: Antioxidant activity; Antioxidants; Caffeoylquinic acids; Carbohydrate hydrolysing enzymes; Phytochemicals; Traditional fruits.

MeSH terms

Antioxidants* / analysis
Chemometrics
Fruit* / chemistry
Metabolomics
Plant Extracts / pharmacology

Substances

Antioxidants
Plant Extracts