Phenolics and polyphenolics in foods, beverages and spices: Antioxidant activity and health effects – A review

Consumption of fruits and vegetables has been shown to be effective in the prevention of chronic diseases. These benefits are often attributed to the high antioxidant content of some plant foods. Apples are commonly eaten and are large contributors of phenolic compounds in European and North American diets. The peels of apples, in particular, are high in phenolics. During applesauce and canned apple manufacture, the antioxidant-rich peels of apples are discarded. To determine if a useful source of antioxidants is being wasted, the phytochemical content, antioxidant activity, and antiproliferative activity of the peels of four varieties of apples (Rome Beauty, Idared, Cortland, and Golden Delicious) commonly used in applesauce production in New York state were investigated. The values of the peels were compared to those of the flesh and flesh + peel components of the apples. Within each variety, the total phenolic and flavonoid contents were highest in the peels, followed by the flesh + peel and the flesh....

Antioxidant activity of apple peels

Phenolics in cereals, fruits and vegetables: Occurrence, extraction and analysis

The dietary consumption of grape and its products is associated with a lower incidence of degenerative diseases such as cardiovascular disease and certain types of cancers. Most recent interest has focused on the bioactive phenolic compounds in grape. Anthocyanins, flavanols, flavonols and resveratrol are the most important grape polyphenols because they possess many biological activities, such as antioxidant, cardioprotective, anticancer, anti-inflammation, antiaging and antimicrobial properties. This review summarizes current knowledge on the bioactivities of grape phenolics. The extraction, isolation and identification methods of polyphenols from grape as well as their bioavailability and potential toxicity also are included.

https://www.mdpi.com/1422-0067/11/2/622/pdf

Biological Activities of Polyphenols from Grapes

A review on protein–phenolic interactions and associated changes

Dietary antioxidants, such as water-soluble vitamin C and phenolic compounds, as well as lipid-soluble vitamin E and carotenoids, present in vegetables contribute both to the first and second defense lines against oxidative stress. As a result, they protect cells against oxidative damage, and may therefore prevent chronic diseases, such as cancer, cardiovascular disease, and diabetes. Brassica vegetables, which include different genus of cabbage, broccoli, cauliflower, Brussels sprouts, and kale, are consumed all over the world. This review focuses on the content, composition, and antioxidant capacity both lipid- and water-soluble antioxidants in raw Brassica vegetables. The effects of post-harvest storage, industrial processing, and different cooking methods on stability of bioactive components and antioxidant activity also are discussed.

Natural antioxidants and antioxidant capacity of Brassica vegetables : A review

Dietary inhibitors of fats and carbohydrates degrading enzymes can reduce obesity and type 2 diabetes. In this study, we screened crude extracts from 30 commonly consumed fruits to test their in vitro inhibitory effect against key enzymes relevant for obesity (pancreatic lipase) and type 2 diabetes (α-glucosidase and α-amylase), total phenolic content (Folin–Ciocalteu method), and antioxidant capacity (ABTS and FRAP). The IC50 values of the fruits tested varied from 39.91 to >400 mg/mL, from 1.04 to >80 mg/mL, and from 0.72 to 135.07 mg/mL against α-glucosidase, α-amylase, and pancreatic lipase, respectively. Antioxidant capacity ranged from 0.66 to 124.66 μmol of TE/g of fruit and strongly correlated with phenolic content, while the enzyme inhibition was poorly correlated with total phenolic and antioxidant capacity. Among fruits tested, blue honeysuckle and red gooseberry exhibited the highest inhibitory activity with respect to the carbohydrate degrading enzymes, while lingonberry had the strongest ant...

In vitro inhibitory effect on digestive enzymes and antioxidant potential of commonly consumed fruits.

Comparison of PrestoBlue and MTT assays of cellular viability in the assessment of anti-proliferative effects of plant extracts on human endothelial cells

Ten apple varieties, harvested at commercial maturity, were analysed, paying special attention to the level of phenolic compounds and polyphenol oxidase (PPO) activity. The results pointed to great quantitative differences in the composition of the apple varieties, and particularly in their phenolic contents. Their total polyphenol content ranged from 2.3 to 3.6 g/kg. Chlorogenic acid was the main phenolic compound found in the varieties studied, and its concentrations varied from 30 to 430 mg/kg, and were 4–20 times higher than those of catechins. Only in Szampion and Elstar were the concentrations of catechins higher. Amongst the flavanol monomers, the main compound was (–)epicatechin, whose concentration varied from 18 to 89 mg/kg. The (+)catechin concentration ranged from 4 to 21 mg/kg. The dominant proanthocyanidins were oligomers up to trimers. In Warta apples, the concentrations of these oligomers were about 3 times higher than those of monomers. The level of PPO activity ranged from 270 units (U)/g in Szampion to 3120 U/g in Warta. No correlation was found between the concentrations of certain phenolic compounds, nor between PPO activity and phenolic or ascorbic acid concentrations. The results gave important information regarding the best use of the apple varieties investigated, i.e. for direct consumption due to their high nutritional value, or for processing.

Compositional characterisation of some apple varieties

Dietary antioxidants, such as water-soluble vitamin C and phenolic compounds, as well as lipid-soluble vitamin E and carotenoids, present in vegetables contribute both to the first and second defense lines against oxidative stress. As a result, they protect cells against oxidative damage, and may therefore prevent chronic diseases, such as cancer, cardiovascular disease, and diabetes. Brassica vegetables, which include different genus of cabbage, broccoli, cauliflower, Brussels sprouts, and kale, are consumed all over the world. This review focuses on the content, composition, and antioxidant capacity both lipidand water-soluble antioxidants in raw Brassica vegetables. The effects of post-harvest storage, industrial processing, and different cooking methods on stability of bioactive components and antioxidant activity also are discussed. r 2005 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Anna Podsędek

Papers

Natural antioxidants and antioxidant capacity of Brassica vegetables : A review

In vitro inhibitory effect on digestive enzymes and antioxidant potential of commonly consumed fruits.

Comparison of PrestoBlue and MTT assays of cellular viability in the assessment of anti-proliferative effects of plant extracts on human endothelial cells

Compositional characterisation of some apple varieties

Natural antioxidants and antioxidant capacity of Brassica vegetables: A review