After blending the triblock copolymer, poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) (PEO-b-PPO-b-PEO) with novolac-type phenolic resin, Fourier transform infrared spectroscopy revealed that the ether groups of the PEO block were stronger hydrogen bond acceptors for the OH groups of phenolic resin than were the ether groups of the PPO block. Thermal curing with hexamethylenetetramine ...

We used DPPH scavenging assays to study the antioxidant activity of three native Polish species of blackberry leaves (Rubus kuleszae Ziel., R. fabrimontanus (Sprib.) Sprib. and R. capitulatus Utsch.). All the studied extracts (methanolic, water, methanolic-water) showed high DPPH free radical scavenging activity (IC50 450.0–186.0 μg/ml). The most effective of the studied species was Rubus kules...

Because of their antioxidative capability polyphenols and vitamins are the most important naturally occurring compounds. Several widely consumed vegetables are rich in various phenolic compounds and vitamins. In this study, such vegetables as tomato (Solanum lycopersicum), eggplant (Solanum melongena), chilli pepper (Capsicum annuum), and potato (Solanum tuberosum) of the Solanaceae family were...

Omega-3 polyunsaturated fatty acids (ω3 PUFAs) from fish oils promote well-established health and antiaging benefits that justify their use as functional ingredients in dietary supplements, healthy foods, and nutraceutical products. Dietary supply is needed because human metabolism exhibits limited to synthesize ω3 PUFAs. However, the practical use of such lipids as food ingredients is often li...

*Corresponding author e-mail: [email protected] A b s t r a c t. The aim of the present study was to reveal an effective extraction procedure for maximization of the yield of steviol glycosides and total phenolic compounds as well as antioxidant activity in stevia extracts. Ultrasound assisted extraction was compared with conventional solvent extraction. The examined solvents were water (100oC/24 ...

Propolis is a resinous hive product Kv bees. The versatile biological activities of propolis, such as its antibacterial, antiviral, fungicidal, anti­ ulcer, immunostimulating, hypotensive and cytosta­ tic properties, as well as its successful clinical applica­ tions [1 — 3] have created an increasing interest in its chemical composition. The last appears to be very complex — the bees collect pr...

Chocolate contains a wide range of antioxidants that includes soluble phenolic compounds (phenolic acids, catechin, epicatechin, and proanthocyanidins), insoluble polymeric phenolics and methylxanthines. The objective of this study was to determine phenolic and theobromine contents in dark (DC), milk (MC), and white (WC) chocolates commonly found in the Malaysian marketplace. Total phenolic and...

Phenolic compounds belong to a class of secondary metabolites and are implicated in a wide range of responsive mechanisms in plants triggered by both biotic and abiotic elicitors. In this study, we approached the combinational effects of ethylene and MeJA (methyl jasmonate) on phenolic compounds profiles and gene expressions in the medicinal plant Catharanthus roseus. In virtue of a widely non-...

Phenolic compounds in grapes and wine are grouped within the following major classes: stilbenes, phenolic acids, ellagitannins, flavan-3-ols, anthocyanins, flavonols, and proanthocyanidins. Consumption of foods containing phenolic substances has been linked to beneficial effects toward chronic diseases such as coronary heart disease and colorectal cancer. However, such correlations need to be s...

Total phenolic contents, antioxidant activity and chemical composition of propolis samples from three localities of Minas Gerais state (southeast Brazil) were determined. Total phenolic contents were determined by the Folin-Ciocalteau method, antioxidant activity was evaluated by DPPH, using BHT as reference, and chemical composition was analyzed by GC/MS. Propolis from Itapecerica and Paula Câ...