Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry), and Ericaceae (blueberry, cranberry), belong to the best dietary sources of bioactive compounds (BAC). They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins) and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits.

Quercetin is the great representative of polyphenols, flavonoids subgroup, flavonols. Its main natural sources in foods are vegetables such as onions, the most studied quercetin containing foods, and broccoli; fruits (apples, berry crops, and grapes); some herbs; tea; and wine. Quercetin is known for its antioxidant activity in radical scavenging and anti-allergic properties characterized by stimulation of immune system, antiviral activity, inhibition of histamine release, decrease in pro-inflammatory cytokines, leukotrienes creation, and suppresses interleukin IL-4 production. It can improve the Th1/Th2 balance, and restrain antigen-specific IgE antibody formation. It is also effective in the inhibition of enzymes such as lipoxygenase, eosinophil and peroxidase and the suppression of inflammatory mediators. All mentioned mechanisms of action contribute to the anti-inflammatory and immunomodulating properties of quercetin that can be effectively utilized in treatment of late-phase, and late-late-phase bronchial asthma responses, allergic rhinitis and restricted peanut-induced anaphylactic reactions. Plant extract of quercetin is the main ingredient of many potential anti-allergic drugs, supplements and enriched products, which is more competent in inhibiting of IL-8 than cromolyn (anti-allergic drug disodium cromoglycate) and suppresses IL-6 and cytosolic calcium level increase.

The study objective was to investigate total phenolic content using Folin-Ciocalteu’s method, to assess nine phenols by HPLC, to determine antioxidant capacity of the water soluble compounds (ACW) by a photochemiluminescence method, and to calculate the correlation coefficients in commercial algal food products from brown (Laminaria japonica, Eisenia bicyclis, Hizikia fusiformis, Undaria pinnatifida) and red (Porphyra tenera, Palmaria palmata) seaweed, green freshwater algae (Chlorella pyrenoidosa), and cyanobacteria (Spirulina platensis). HPLC analysis showed that the most abundant phenolic compound was epicatechin. From spectrophotometry and ACW determination it was evident that brown seaweed Eisenia bicyclis was the sample with the highest phenolic and ACW values (193 mg·g⁻¹ GAE; 7.53 µmol AA·g⁻¹, respectively). A linear relationship existed between ACW and phenolic contents (r = 0.99). Some algal products seem to be promising functional foods rich in polyphenols.

On a global scale, people are demanding more attractive and tasty food. Both the quality of foodstuffs and aesthetic aspects contribute to the appearance of consumed meals. The attraction and appeal of individual dishes could be enhanced by edible flowers. New information concerning the composition and nutritional value of edible flowers is also important and represents a sufficient reason for their consumption. The aim of this study is to contribute to the popularization of some selected edible flowers of ornamental plants involving altogether 12 species. The flowers were used to determine their antioxidant capacity, which fluctuated between 4.21 and 6.96 g of ascorbic acid equivalents (AAE)/kg of fresh mass (FM). Correlation coefficients between antioxidant capacity and the contents of total phenolics and flavonoids were r² = 0.9705 and r² = 0.7861, respectively. Moreover, the results were supplemented with new data about the mineral composition of edible flowers (mostly, not found in the available literature). The highest levels of mineral elements were observed in the flowers of species Chrysanthemum, Dianthus or Viola. The most abundant element was potassium, the content of which ranged from 1,842.61 to 3,964.84 mg/kg of FM.

In recent years, growing attention has been focused on the utilization of natural sources of antioxidants in the prevention of chronic diseases. Black chokeberry (Aronia melanocarpa) represents a lesser known fruit species utilized mainly as juices, purees, jams, jellies and wine, as important food colorants or nutritional supplements. The fruit is valued as a great source of antioxidants, especially polyphenols, such as phenolic acids (neochlorogenic and chlorogenic acids) and flavonoids (anthocyanins, proanthocyanidins, flavanols and flavonols), particularly cyanidin-3-galactoside and cyanidin-3-arabinoside, as well as (−)-epicatechin units. The berries of A. melanocarpa, due to the presence and the high content of these bioactive components, exhibit a wide range of positive effects, such as strong antioxidant activity and potential medicinal and therapeutic benefits (gastroprotective, hepatoprotective, antiproliferative or anti-inflammatory activities). They could be also contributory toward the prevention of chronic diseases including metabolic disorders, diabetes and cardiovascular diseases, because of supportive impacts on lipid profiles, fasting plasma glucose and blood pressure levels.