Sources and Chemistry of Flavonoids; their Biological and Therapeutic Potential

Abstract

Flavonoids are natural polyphenolic compounds, which are responsible for the taste and colors of medicinal plants, herbs, fruits, vegetables. Fruits (e.g., Berries, cherries, plums, apples, lemons, oranges, and grapes etc) and vegetables (e.g., broad beans, olives, onions, spinach, shallot etc) are the main sources of flavonoids. They also exist abundantly in cocoa products, black and green tea, red wine, red pepper, chamomile, celery, parsley, ginkgo, and mint. Flavonoids derivatives can also be synthesized through esterification, halogenation, alkoxylation, alkylation, aromatic hydroxylation, acylation and conjugation with various organic compounds. Flavonoids can be supplemented in a staple of food as nutraceutical agents and have an important role in human diet. They possess diverse biological activities including anti-inflammation, anti-oxidation, anti-cancer, anti-diabetes, anti-obesity, antimutagenic, neuroprotective and also have beneficial effects on oxidative stress, inflammation, insulin resistance, lipid metabolism and neurodegenerative diseases (e.g., amyotrophic lateral sclerosis, Huntington’s disease, Parkinson’s disease and Alzheimer’s disease). Flavonoids contain a 15-carbon skeleton; the basic structure consists of a flavan nucleus, a combination of two benzene and one pyran rings. Flavonoids are divided into eight important groups i.e., flavones, flavanols, isoflavones, flavan-3-ols, flavanonols, anthocyanidins, chalcones, and flavanones. A structure-activity relationship exists between flavonoids and their antioxidant activities. Flavonoids are effective in chelating metal ions and scavenging free radicals. The antioxidant properties of flavonoids are governed by their –OH groups, differences in hydrophobicity and molecular planarity.

Synergistic Antibacterial Screening of Cymbopogon citratus and Azadirachta indica: Phytochemical Profiling and Antioxidant and Hemolytic Activities

“…They find important medicinal value due to their antioxidation, anticancer, anti-inflammation, antiobesity, antidiabetes, neuroprotective, antimutagenic properties, etc. 43 The reported literature also suggests that C. citratus is rich in TFC and TPC. 44 , 45 Their presence in A. indica has also been suggested in earlier studies.…”

“…Flavonoids are natural polyphenolic compounds that produce the color and taste in various parts of herbs, vegetables, plants, and fruits. They find important medicinal value due to their antioxidation, anticancer, anti-inflammation, antiobesity, antidiabetes, neuroprotective, antimutagenic properties, etc . The reported literature also suggests that C.…”

Antioxidant Properties of Azadirachta Indica Leave Extracts

“…Plant materials show antioxidant activities due to the flavonoids [24,25] and phenolics content [26,27]. Flavonoids are responsible for the taste and color of plants, herbs, vegetables, and fruits [27].…”

“…Plant materials show antioxidant activities due to the flavonoids [24,25] and phenolics content [26,27]. Flavonoids are responsible for the taste and color of plants, herbs, vegetables, and fruits [27]. Flavonoids are compounds that have low molecular weight and are extracted from different parts of the plant.…”

Identification of Ajuga Iva Extracts as Potential Candidates for Antidysmenorrhea Targeting Human COX2 and PGE2S‐1 through In Vitro and In Silico Drug Repurposing Approach

“…Plant components used in traditional medicine exert their pharmaceutical effects through their ability to bind to plasma proteins. [45] Indeed, Liu et al 2008 reported that albumin has a high affinity for many flavonoids with hydrophobic interaction, which could explain the protective activity of polyphenols against thermal denaturation of albumin. [46] The denaturation of tissue-specific proteins is a crucial factor in the development of inflammatory and autoimmune disorders, such as arthritis.…”