title: Antioxidant property enhancement of sweet potato flour under simulated gastrointestinal pH.
abstract: Sweet potato is known to be rich in healthful antioxidants, but the stability of its antioxidant properties under gastrointestinal pH is very much unknown. Hence, this study aimed to evaluate the changes in antioxidant properties (total contents of phenolics and flavonoids as well as antioxidant activity) of sweet potato flour (SPF) under simulated gastrointestinal pH conditions. It was found that the yield of SPF crude phenolic extract increased from 0.29 to 3.22 g/100 g SPF upon subjection to gastrointestinal pH conditions (p < 0.05). Also elevated significantly were the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of SPF (p < 0.05). In summary, the antioxidant properties of SPF were enhanced under gastrointestinal pH conditions, suggesting that SPF might possess a considerable amount of bound phenolic and other antioxidative compounds. The antioxidant properties of SPF are largely influenced by pH and thus might be enhanced during the in vivo digestive process.
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Kim Wei
authors.initials: KW
authors.lastname: Chan
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Nicholas M H
authors.initials: NMH
authors.lastname: Khong
authors.affiliation: Department of Chemistry, University of Sargodha, Sargodha 40100, Pakistan.
authors.forename: Shahid
authors.initials: S
authors.lastname: Iqbal
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Imam Mustapha
authors.initials: IM
authors.lastname: Umar
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Maznah
authors.initials: M
authors.lastname: Ismail
mesh_terms: D000975:Antioxidants / Q000737:chemistry*; D005433:Flour; D005750:Gastric Juice / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D027723:Ipomoea batatas / Q000737:chemistry*
chemical_list: D000975:Antioxidants