Phenolic extracts of the leaves ofPsidium guineenseSw. improve the shelf life of sunflower oil and baked cake and antioxidant status of Wistar rats

Abstract

The potential of the ethanolic extract of Psidium guineense Sw. leaves (PGLE) to protect food from oxidation was evaluated using sunflower oil and baked cake as food models. The nutritional quality of PGLE was evaluated by feeding Wistar rats with PGLE for 150 days. Psidium guineense Sw. leaves contain 195.25 ± 9.56 mg g–1 phenolic substances, 51% of which are o‐diphenols. Protection factor, the ability of Psidium guineense Sw. leaves to protect sunflower oil against oxidation (1.82 ± 0.13), was not significantly affected by heat treatment compared to BHT. Formation of oxidation products, peroxide and hexanal in PGLE‐ and BHT‐added cake was significantly lower (<5 ppm over 28 days) compared to control with no added antioxidants. Therefore, addition of PGLE improved the shelf life of sunflower oil and oxidative stability of baked cake. PGLE also improves the serum antioxidant capacity and inhibits lipid and protein oxidation in Wistar rats. Practical applications PGLE is a rich source of phenolic substances. Due to high antioxidant activity, pleasant sensory quality and high thermal stability, PGLE can be used to improve the shelf life of baked cake and edible oils. As PGLE also improves serum and plasma antioxidant properties without causing any toxicity, nutritional food supplements can be developed based on PGLE.

Improvement of Oxidative Stability and Microbial Shelf Life of Vanilla Cake by Coconut Oil Meal and Sesame Oil Meal Phenolic Extracts

“…Galangin was used as the internal standard (ISTD). Phenolic compounds of CME and SME were identified by comparison of the retention times and UV spectra of authentic standards in HPLC as reported [15].…”

“…Preparation of Vanilla Cake. Cake samples were prepared by mixing CME or SME or BHT to give 20 mg/ 100 g of margarine added to the cake according to a reported procedure [15]. Control cake was prepared without adding any antioxidant extract.…”

Antioxidant and Nutritional Properties of Domestic and Commercial Coconut Milk Preparations

“…Thiobarbituric acid reactive substances (TBARS) were measured using linoleic acid as an external source of polyunsaturated fatty acids according to a previously published method with some modifications [ 14 , 18 ]. Linoleic acid was homogenized in Tween 20 and H 2 O mixture (1 : 2000 v / v , respectively) at room temperature for 5 min at 250 rpm.…”

Effect of chain length and saturation of the fatty acids in dietary triglycerides on lipid metabolism in Wistar rats

“…The antioxidant activity was expressed as Trolox equivalent antioxidant capacity (TEAC). DPPH radical scavenging activity of serum was determined according to a reported method (Senanayake et al, 2018).…”