Blackberry polyphenols: review of composition, quantity, and health impacts from in vitro and in vivo studies

Abstract

Blackberries possess marked concentrations of antioxidant polyphenols, most notably anthocyanins, ellagic acid, ellagitannins, epi/catechin, and proanthocyanidins. While the quantity and type of polyphenols can vary, cyanidin-3-O-glucoside (C3G) is consistently the most abundant polyphenol found in blackberries. Though blackberry antioxidants have not demonstrated significant bioavailability or bioaccessibility in their native form, emerging research suggests that antioxidant metabolites, such as protocatechuic acid derived from C3G, may account for some of the in vivo benefits. Cell studies conducted with blackberry phenolic extracts have demonstrated anti-inflammatory, chemopreventive, and neuroprotective effects; whereas, animal models given blackberries have exhibited reduced insulin resistance, attenuated weight gain, and a decrease in inflammatory markers. Blackberry consumption can lead to positive health outcomes. In human health cross-sectional and longitudinal studies, fresh berry consumption has been associated with better long-term insulin resistance, cognitive function, bone density, and cardiovascular function. Research studies, combining in vitro digestion and absorption with targeted cell studies, are being performed to better understand the metabolism and bioactivity of blackberry phenolics. These compounds are not only absorbed by the body, but also can attach to the lining of the digestive tract or be fermented in the colon, contributing to the health outcomes afforded by blackberry consumption.

Polyphenols and Antioxidant Activity of Citrus Fiber/Blackberry Juice Complexes

“…Blackberries contain numerous bioactive compounds. In addition to polyphenols, which are of great interest for the food and nutraceutical industries, the presence of other components, such as fibers, vitamins, minerals and sugars, is also significant [ 4 , 5 ]. Polyphenols are naturally occurring compounds formed as secondary metabolites in plants, which, due to their structural complexity, are classified into phenolic acids, flavonoids, tannins, stilbenes, coumarins and polymeric ligands [ 6 ].…”

“…In addition to cyanidin 3-glucoside, which is the most abundant anthocyanin in blackberries [ 7 ], many phenolic acids, tannins and other anthocyanins are also present, contributing to the high antioxidant capacity of these plants [ 8 , 9 ]. The chemical composition of blackberries and the content of polyphenols depend on the varieties, growing conditions, location, stage of maturity and harvest [ 5 ]. Interest in the healing properties of blackberries dates back to the sixteenth century in Europe, where they were used to relieve infections of the eyes and mouth [ 10 ].…”

“…Interest in the healing properties of blackberries dates back to the sixteenth century in Europe, where they were used to relieve infections of the eyes and mouth [ 10 ]. Consumption of blackberries, as well as other products rich in polyphenols, was associated with the prevention of cardiovascular diseases [ 11 ] and antimicrobial, anticancer, antimutagenic, neuroprotective, antiproliferative and anti-inflammatory activity [ 5 , 10 , 12 ]. In addition to the consumption of fresh blackberries, blackberries are used to make many products, such as jams, juices, purees, sauces, cakes, ice cream, pies/cobblers, marmalade, wine, liqueurs, canned and dried blackberries [ 13 , 14 ].…”

A Review on Chromatography–Mass Spectrometry Applications on Anthocyanin and Ellagitannin Metabolites of Blackberries and Raspberries

“…Over recent years, research studies, combining in vitro digestion and absorption with targeted cell assessment, have been used to elucidate the metabolism and bioactivity after consumption of berries, including blackberries [88]. (Poly)phenol metabolites are not only absorbed in the blood circulation, but they can also get attached to the surface of the GIT or get subjected to further colonic fermentation [88].…”

Examining the Performance of Two Extraction Solvent Systems on Phenolic Constituents from U.S. Southeastern Blackberries

“…Two dominant classes of phenolics in blackberries are anthocyanins and hydrolyzable tannins [ 1 , 2 ]. Other phenolics are present and include phenolic acids, flavan-3-ols, and flavonols such as quercetin, kaempferol, isorhamnetin and their glycosylated derivatives [ 3 , 4 ]. Anthocyanins are colorful O -glycosidic pigments with a flavylium cation that have been long recognized for their health-promoting potential.…”