L. Erasmus
G. Weber
Corresponding Author: admin@greenbio.co.za
Phenolic compounds are seen as phytochemicals, also a main class of secondary metabolites, distributed in a large number of foods and beverages. The main dietary phenolic compounds include phenolic acids, flavonoids and tannins.
The basic structure of flavones is a 1, 4-benzopyrone with a phenyl substitution in the 2-position. Flavonoids have a different number and position of substitutions in the aromatic ring and differ in the extent and character of oxidation in the pyrone portion of the molecule. Flavonoids are usually found in the form of glycosides in nature due to the hydroxyl groups which combines with sugars. The most prosthetic group is glucose, but other sugars like glucuronic and galacturonic acid have been identified.
The Joint committee on Biochemical Nomenclature of the American Society of Biological Chemists and the American Institute of Nutrition (1950) recommended the term ‘bioflavonoids’ to encompass the many flavonoids which show some form of biological activity. The Committee on Dietary Allowances of the Food and Nutrition Board, categorized bioflavonoids as pharmacological rather than nutritional agents because they are nonessential substances in food with biological effects. Several bioflavonoids can protect sensitive and important biological compounds due to being effective antioxidants. Furthermore, studies confirmed that flavonoids are able to chelate metals to form metal complexes.
Recent studies positively correlated the improvement of various (chronic, inflammation and oxidative stress related) diseases with the intake of foods and beverages high in phenolic compounds. Herewith the antioxidant potential of phenolic compounds in fruits and vegetables are commonly praised but moreover, the biological activities of phenolic compounds have also recently attracted attention due to their many possible health related properties. The antioxidant mechanism is thought to be very important, being responsible for the reduction of lipid oxidation in (animals and plant) tissues, which conserves the quality of the food in the human diet and reduces the risk of developing various diseases.
Recent studies positively correlated the improvement of various (chronic, inflammation and oxidative stress related) diseases with the intake of foods and beverages high in phenolic compounds. Herewith the antioxidant potential of phenolic compounds in fruits and vegetables are commonly praised but moreover, the biological activities of phenolic compounds have also recently attracted attention due to their many possible health related properties. The antioxidant mechanism is thought to be very important, being responsible for the reduction of lipid oxidation in (animals and plant) tissues, which conserves the quality of the food in the human diet and reduces the risk of developing various diseases.
The interpretation of many recent studies must however be done with caution, as these studies are performed in environments not always replicating the conditions that occur inside a living organism, hence not predicting the reaction of an entire system of a living being with absolute certainty. The aim of this article is to review the content of a Phenol Plus product containing important phenolic compounds such as Naringin, Neo-Hesperidin, Hesperidin, Quercetin. These phenolic compounds may have general health related properties which is mainly due to their antioxidant properties.
Oxidative processes occur in living organisms and are responsible for the generation of free radicals which attack cells and lead to serious diseases.
Phenolic compounds are able to donate a hydrogen atom and/ or electron to free radicals, which breaks the chain reaction of oxidation. The capacity of phenolic compounds to exert an antioxidant effect depends on their molecular structure, particularly their number, location and positions of the hydroxyl groups, and the double bonds (see figure 1). These compounds are beneficial for health by inhibiting or delaying the oxidation of DNA, proteins and lipids.
Inflammation can easily be caused by pathogens, injuries or the effects chemicals or radiation. Phenolic compounds are also able to participate when inflammatory responses occur by exerting an anti-inflammatory action. These actions contribute in the reduction/ inhibition of prostaglandin synthesis throughout the body by blocking the enzyme (cyclooxygenase) responsible for the production of prostaglandins.
Quercetin has been examined as treatment for many conditions. It has served as a beneficial treatment for allergies, metabolic and inflammatory disorders, heart and eyes diseases and showed anticancer and antiviral actions. It exhibited pharmacological properties against various pathogenic bacteria, viruses and parasites. Quercetin treatment showed beneficial effects against Alzheimer’s disease due to its ability to inhibit the effect of acetylcholinesterase which may ease the symptoms of Alzheimer’s for a while.
Moreover, in an animal model researchers found that it minorly improved their ability to learn and memorize which indicates that it could be used in the case of neurodegenerative diseases. It has been found that quercetin possess anti-carcinogenic and hepaprotective effects. In another clinical trial, quercetin treatment also improved adiponectin-mediated insulin resistance of women with polycystic ovary syndrome as well as their hormonal profile.
Hesperidin has been studied for its numerous effects on different health related conditions. Research found that it exerts sedative/ sleep effects by inducing changes in the chemical reactions in cells within different areas of the brain in mice. It had therapeutic effects on vascular system disorders, fragility and permeability. It was reported to possess great anti-inflammatory effects on inflammatory diseases. In clinical trials, it also successfully reduced lipid peroxidation levels in muscle, resulting in decreased muscle damage and injury.
Hesperidin has been studied for its numerous effects on different health related conditions. Research found that it exerts sedative/ sleep effects by inducing changes in the chemical reactions in cells within different areas of the brain in mice. It had therapeutic effects on vascular system disorders, fragility and permeability. It was reported to possess great anti-inflammatory effects on inflammatory diseases. In clinical trials, it also successfully reduced lipid peroxidation levels in muscle, resulting in decreased muscle damage and injury.
Hesperidin had several effects on hormonal disorders in women and on the action of various enzymes including an inhibitory effect on hyaluronidase, human acrosin, aromatase, aldol reductase, alkaline phosphate in rat serum and a weak in vitro activity against alpha-glucosidase. It stimulated cyclooxygenase enzyme. Evidence was also found that it inhibited epinephrine induced lipolysis and prostaglandins in rats when used against sponge-induced granuloma.
More pharmacological effects include antibacterial, antifungal, antiviral and anti-yeast activity. Also, (in circumstances where it might be useful) anti-fertility actions and anticarcinogenic activity. It showed protective activities to oxidative stress caused by ultraviolet irradiation and it inhibited cell and platelet aggregation.
As with hesperidin, neo-hesperidin also had minor sedative effects which induced changes in the chemical reactions in cells within different areas of the brain. It showed protective actions against gastric lesions and gastritis. In another study, neo-hesperidin administration was the most effective in reducing the accumulation of reactive oxygen species in yeast. These findings indicate that neo-hesperidin has potential in being an anti-aging agent.
It was also acknowledged as a non-toxic and multi-potent agent in Alzheimer’s disease therapeutics. Neo- hesperidin showed actions of inhibiting fibrillar formation in the brain which is commonly seen in Alzheimer’s disease brains. Furthermore, it had an indirect preventative action against colorectal cancer by modulating the bacterial microbiome in the gut; showing antibacterial effects against harmful bacteria and increasing favourable microorganisms.
Naringin has been studied due to its wide range of pharmacological activities. Research indicated that it interacted with signalling molecules and was able to modulate signalling pathways involved in many processes in living organisms. It showed an anti-inflammatory role in hepatitis, ulcerative colitis and pneumonia. In an animal model study, naringin treatment was also able to noticeably reduce the size of oesophageal, breast, cervical and bladder tumours indicating effective anticancer activities. It had beneficial effects on bone regeneration, metabolic syndromes, genetical damage and on central nervous system diseases such as Alzheimer’s disease, Parkinson’s disease and epilepsy.
In extreme cases, when phenolic compounds are taken in doses higher than recommended, it can cause nausea, headaches or a tingling effect. Studies recommend cautious use of quercetin with antibiotics, cyclosporin, warfarin or other drugs that are changed by the liver and for people with kidney diseases. Quercetin can have moderate interactions with these drugs and further damaging effects on the kidneys. Other authors also stated that hesperidin can interfere with blood clotting abilities.
Always consult a health practitioner when pregnant or breast-feeding before taking flavonoid supplements.
Flavonoid supplements are mostly safe to use as these compounds are natural. According to researchers they have promising potential as supplements with health-related benefits.
Albuquerque, B.R., Heleno, S.A., Oliveira, M.B.P., Barros, L. and Ferreira, I.C., 2021. Phenolic compounds: current industrial applications, limitations and future challenges. Food & Function, 12(1), pp.14-29.
Andres, S., Pevny, S., Ziegenhagen, R., Bakhiya, N., Schäfer, B., Hirsch‐Ernst, K.I. and Lampen, A., 2018. Safety aspects of the use of quercetin as a dietary supplement. Molecular nutrition & food research, 62(1), p.1700447.
Batiha, G.E.S., Beshbishy, A.M., Ikram, M., Mulla, Z.S., El-Hack, M.E.A., Taha, A.E., Algammal, A.M. and Elewa, Y.H.A., 2020. The pharmacological activity, biochemical properties, and pharmacokinetics of the major natural polyphenolic flavonoid: quercetin. Foods, 9(3), p.374.
Chen, R., Qi, Q.L., Wang, M.T. and Li, Q.Y., 2016. Therapeutic potential of naringin: an overview. Pharmaceutical biology, 54(12), pp.3203-3210. D’Andrea, G., 2015. Quercetin: a flavonol with multifaceted therapeutic applications? Fitoterapia, 106, pp.256-271.
Garg, A., Garg, S., Zaneveld, L.J.D. and Singla, A.K., 2001. Chemistry and pharmacology of the citrus bioflavonoid hesperidin. Phytotherapy research, 15(8), pp.655-669.
Karim, N., Shishir, M.R.I., Gowd, V. and Chen, W., 2021. Hesperidin-An Emerging Bioactive Compound against Metabolic Diseases and Its Potential Biosynthesis Pathway in Microorganism. Food Reviews International, pp.1-23.
Martínez, M.C., Fernandez, S.P., Loscalzo, L.M., Wasowski, C., Paladini, A.C., Marder, M., Medina, J.H. and Viola, H., 2009. Hesperidin, a flavonoid glycoside with sedative effect, decreases brain pERK1/2 levels in mice. Pharmacology Biochemistry and Behavior, 92(2), pp.291-296.
Minatel, I.O., Borges, C.V., Ferreira, M.I., Gomez, H.A.G., Chen, C.Y.O. and Lima, G.P.P., 2017. Phenolic compounds: Functional properties, impact of processing and bioavailability. Phenolic Compd. Biol. Act, 8, pp.1-24.
Nagula, R.L. and Wairkar, S., 2019. Recent advances in topical delivery of flavonoids: A review. Journal of controlled release, 296, pp.190-201.
Parhiz, H., Roohbakhsh, A., Soltani, F., Rezaee, R. and Iranshahi, M., 2015. Antioxidant and anti‐inflammatory properties of the citrus flavonoids hesperidin and hesperetin: an updated review of their molecular mechanisms and experimental models. Phytotherapy Research, 29(3), pp.323-331.
Rice-Evans, C., Miller, N. and Paganga, G., 1997. Antioxidant properties of phenolic compounds. Trends in plant science, 2(4), pp.152-159. Zhao, Y. and Liu, S., 2021. Bioactivity of naringin and related mechanisms. Die Pharmazie-An International Journal of Pharmaceutical Sciences, 76(8), pp.359-363.