Grape is a phenol-packed plant that is mostly distributed in the seed, skin, leaf and stem of grape. Grapes belong to the family of Vitaceae of which the three main species are French hybrids, European grapes (Vitis vinifera), and North American grapes (Vitis labrusca and Vitis rotundifolia). Grapes can bear seeds or can be seedless and are also categorised as raisin grapes, table grapes and wine grapes (for winemaking). Due to the high nutritional and medicinal properties of grapes, their seeds and leaves have been used since time immemorial as home remedies for tackling diseases. A regular consumption of grapes has been linked with a minimal occurrence of degenerative diseases such as cancer and cardiovascular diseases.Grapes are an excellent source of minerals, vitamins, dietary fibres, carbohydrates and phytochemicals. The most important phytochemicals in grapes are the polyphenols due to their active biological activities and health-boosting benefits. The phenolic compounds present in grapes are phenolic acids, anthocyanins, proanthocyanidins, stilbenes (resveratrol) and flavanols. The flavonoids in grapes are present in the stems and seeds and they contain procyanidin polymers, (−)-epicatechin and (+)-catechins. Anthocyanins are pigments that are found in the grapes skins and they are the main polyphenolics present in red grapes, while flavan-3-ols are mostly found in the white species of grapes. Anthocyanins pigments contribute immensely to the colour of grapes. Proanthocyanidins are also the phenolic compounds present in the seeds and skins of grapes.
The proanthocyanidins found in grape seeds possess potent free radical scavenging activity thus act as antioxidants. Grapes seeds contain 40% fiber, 16% oil, 11% proteins, and 7% complex phenols (e.g. tannins). Grapes seeds are excellent sources of flavonoids, Gallic-Acid, essential Fatty Acid-linoleic acid, oligomericproanthocyanidin (OPC), vitamin E and resveratrol. They also contain polymers, monomers, oligomers, dimers and trimers. Studies reveal that grapes possess anti-diabetic, antiplatelet, cardioprotective, anticancer, antioxidant, anti-cholesterol, antiaging, anti-inflammation, antimicrobial properties as well as offer protection against oxidative damage. Grape can be used as a nutritional supplement either in a tablet, capsule or liquid form.
Purple Grapes Benefits of Grapes
Antimicrobial Effects
Researchers have shown that grape wine can inhibit microbial (bacterium causing disease), especially Escherichia coli growth. The inhibition tends to increase as the polyphenol concentration increases. The grape extracts of white wine and alcohol-free red wine exhibited antimicrobial activity to certain pathogens such as Candida albicans, Escherichia coli and Staphylococcus aureus. The polyphenolic compounds found in red wines are believed to be responsible for the antimicrobial effects. Several bacterial species exhibit varying sensitivities to phenolic compounds. Staphylococcus aureus was most sensitive to wine extracts, followed by Escherichia coli and then Candida albicans. Furthermore, the phenolic compounds from various parts of grapes exhibit varying antimicrobial effects. The antimicrobial activity of fermented pomace appears to be more effective than a whole fruit grape extract.
Anticancer Activities
Several studies have revealed that grapes extracts possess anticancer activities. The extract from pomace, post wine production is capable of inhibiting the activities of matrix metalloproteinases-2 and -9. It has a significant antiproliferative effect on human colon adenocarcinoma cells (Caco-2). This implies that the by-product of wine is capable of hindering or fighting against carcinogenesis. A scientific research conducted by the Department of Pharmaceutical Sciences, University of Colorado Health Sciences Center has shown that the consumption of grape seed extract in combination with chemotherapy agents is effective for tackling breast cancer. Test tubes scientific studies have equally shown that grape seed extract can potentially inhibit the growth of cancer cells from the prostate, breast, colon, lung and stomach.
Tackles Circulatory & Vascular Disorders
Grape seed extract helps to prevent and treat circulatory and vascular disorders. It is highly essential for individuals suffering from atherosclerosis and varicose veins. Researchers have revealed that the compounds found in grape seed are capable of minimizing chronic venous insufficiency symptom of pools of blood in the legs. These blood pools tend to cause fatigue, pain, swelling and visible veins on the legs. Due to the circulatory system benefits of the grape seed extract, it is effective for minimizing the risk of blood clots in the heart and brain.
Cardioprotective Effects
Grape polyphenols have protective effects on the heart and blood vessels, thus prevent abnormal heart rhythms, prevent blood vessel narrowing and reduce blood clotting. Phenolic-rich grape juice or grape seed extracts can be used for tackling postprandial hyperlipemia and oxidative stress. These are well-defined risk factors for atherosclerosis. The oxidative stress factors include malondialdehyde-modified-LDL (MDA-LDL), plasma lipid hydroperoxides and serum lipid peroxidation products. Studies show that the lipid-bound polyphenols increased in serum two hours upon consumption of phenolics, while MDA-LDL was detected after six weeks.
Antioxidant Activities
Significant antioxidant activities have been unravelled in grapes thus grape polyphenols are useful for hindering or preventing cell damage caused by oxidation. The antioxidants also scavenge for free radicals, reduce hydroperoxide formation and inhibit lipid oxidation.
Regulates the Cholesterol Level
The polyphenols found in grapes are useful for reducing the oxidation of low-density lipoprotein cholesterol (bad cholesterol). It is noteworthy that if this is left untackled, can lead to the development of atherosclerosis, which is the hardening of the arteries. Grape seed extract promotes good cholesterol (HDL).
Regulates the Blood Pressure
Scientific studies have shown that four weeks of treatment with grape seed extract is capable of reducing both systolic and diastolic blood pressure. Individuals suffering from high blood pressure can benefit from grapes consumption.
Tackles Allergies and Hay Fever
Grape seed extract is useful for tackling allergies and hay fever. The extract inhibits and prevents the production of inflammatory compounds that cause allergic reactions, especially hay fever. Using grape seed extract doesn't cause the unwanted side effects associated with antihistamines.
Suitable for Wrinkles and Sagging Skin
Due to the high antioxidant activities of grape, it prevents free radicals from damaging the collagen fibres. Its anti-inflammatory effect aids the prevention of chronic inflammation from destroying the collagen fibres thereby slowing down the formation of wrinkles.
Recommended for Body Exercises
Grape seed extract is considered effective for minimizing oxidative stress during exercise. Grape is also effective for minimizing the swelling that is associated with sports injuries.
Tackles Oedema
Grape is suitable for tackling oedema, which is a condition characterized by excessive watery fluid that collects in the tissues or cavities of the body. A scientific study on breast cancer patients revealed that the consumption of at least 600 mg of grapes on a daily basis is capable of reducing oedema caused by breast cancer surgery.
White Grapes Anti-inflammation Activities
The phenolic compounds found in grape seeds exhibit significant anti-inflammation effects on both human beings, rats and mice. These compounds include procyanidins (oligomeric flavonoids) and flavanols.
Anti-Tumour Activities
Grape seed extracts possess anti-tumour properties thus supplementing grape seed extracts is considered to be an effective anti-tumour agent.
Anticoagulants or Blood Thinning Effects
Grape seed extract is a powerful blood thinner thus capable of increasing the risk of bleeding when consumed with other blood thinners such as aspirin, clopidogrel (Plavix) or Coumadin. Grape seed extracts should be taken with care or avoided in individuals with bleeding disorders.
Ideal for Diabetic Patients
Researchers attest that patients suffering from complications associated with diabetes can benefit immensely from grapes.
Edible Purposes
Grapes are edible thus can be used for making grapes smoothie, wine, desserts, juice, jam, snacks and jello. The grape seeds can be used for producing grapeseed oil.
Other Uses of Grapes
- The sap of grapevines can be used for producing ointment for treating eye and skin diseases.
- The grape leaves can be used for stopping body aches, pain, inflammation and bleeding.
- Unripe grapes can be used for treating sore throats.
- Dried grapes can be used for tackling constipation and indigestion.
- Gallic acid (a phytochemical) present in grape seeds have both anti-fungal and anti-viral properties.
- Grape seed extract minimizes the risk of prostate cancer
- Grape seed extract increases the cognitive ability of an individual by slowing down the ageing of the brain.
- Grape seed extract strengthens the blood vessels.
DISCLAIMER
This post is for enlightenment purposes only and should not be used as a replacement for professional diagnostic and treatments. Remember to always consult your healthcare provider before making any health-related decisions or for counselling, guidance and treatment about a specific medical condition.
REFERENCES
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- Pixabay (2018), Images via https://pixabay.com/
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