Yazar "Gultekin-Ozguven, Mine" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Orange, red and purple barberries: Effect of in-vitro digestion on antioxidants and ACE inhibitors
    (Elsevier, 2021) Sensu, Eda; Kasapoglu, Kadriye Nur; Gultekin-Ozguven, Mine; Demircan, Evren; Arslaner, Ayla; Ozcelik, Beraat
    Bioactive compounds such as phenolics, anthocyanins and carotenoids were investigated in Berberis plant with purple (PB), red (RB) and orange (OB) fruits (barberries). The study was aimed to evaluate the bioaccessibility of the antioxidants and ACE (angiotensin converting enzyme) inhibitory compounds of barberry plants upon their transit through in-vitro digestion. Among barberries, (PB) exhibited the strongest antioxidant activity due to its higher phenolic and flavonoid content. The order of total phenolics and anthocyanins was PB > RB > OB. Chlorogenic acid was the main phenolic compound in all barberries even after in-vitro digestion. All barberries had similar amounts of total carotenoids (4.45 mg beta-carotene/100gDW). After in-vitro digestion, decreasing phenolics, anthocyanins and carotenoids led to a reduced antioxidant activity. Anthocyanins were found the most sensitive compounds in-vitro digestion. In terms of ACE inhibition activity, only RB exhibited ACE inhibition before (73.84%) and after (65.51%) in-vitro digestion. No ACE inhibition activity was detected at all in RB and OB samples. Leaves and branches of Berberis had also over 50% ACE inhibitory activity. To our knowledge, this is the first study on the carotenoids of barberry and the effect of in-vitro digestion on its bioactive compounds and ACE inhibitors.
  • Küçük Resim Yok
    Öğe
    Recovery of Polyphenols Using Pressurized Hot Water Extraction (PHWE) from Black Rosehip Followed by Encapsulation for Increased Bioaccessibility and Antioxidant Activity
    (Mdpi, 2022) Kasapoglu, Kadriye Nur; Demircan, Evren; Gultekin-Ozguven, Mine; Kruger, Johanita; Frank, Jan; Arslaner, Ayla; Ozcelik, Beraat
    In this work, pressurized hot water extraction (PHWE) of hydrophilic polyphenols from black rosehip fruit was maximized using response surface methodology for simultaneous optimization in terms of extraction yield, total antioxidant capacity, total (poly)phenols, catechin, total monomeric anthocyanins, and cyanidin-3-O-glucoside. Extraction parameters, including temperature (X1: 40-80 degrees C) and the solvent-to-solid ratio (X2: 10-40 mL/g), were investigated as independent variables. Experimentally obtained values were fitted to a second-order polynomial model, and optimal conditions were determined using multiple regression analysis and analysis of variance. The black rosehip extract (BRE) obtained at optimized PHWE conditions was further encapsulated in biopolymer-coated liposomes and spray dried to enhance its processing and digestive stability. After reconstitution, the fabricated particles had an average size of 247-380 nm and a zeta-potential of 15-45 mV. Moreover, encapsulation provided remarkable protection of the phenolics under in vitro gastrointestinal digestion conditions, resulting in up to a 5.6-fold more phenolics in the bioaccessible fraction, which also had 2.9-8.6-fold higher antioxidant activity compared to the nonencapsulated BRE. In conclusion, PHWE in combination with a biopolymer coating is a potent method for the production of stable and safe edible natural extracts for the delivery of (poly)phenolic compounds in food and dietary supplements.