Antioxidants are substances that stable enough to prevent or retard the oxidation of easily oxidisable biomolecules such as lipids, proteins and DNA, thus preventing oxidative damage (Lobo et al. 2010). Antioxidants can be classified into two classes, according to their action, into primary or chain breaking antioxidants and secondary or preventative antioxidants. Primary antioxidants, when present in low concentration, can either delay or inhibit the lipid oxidation by reacting with a lipid radical or peroxyl radicals. Secondary antioxidants on the other hand, retard the rate of oxidation by chelating of metal ions or quenching of singlet oxygen (Amalia et al. 2005). These antioxidants are widely used as food additives in foods, especially those with high lipid content, to protect against oxidative degradation, maintain nutritional quality and increase the shelf life of the food.
Generally, antioxidants can be divided into natural and synthetic antioxidants. Natural antioxidants are normally found in the plant extracts which are believed to exhibit strong antioxidant activity and protection against oxidant-induced damage such as diabetes, neurodegenerative and cardiovascular disease (Maganha et al. 2010). Plants, fruits and vegetables are all known to be rich sources of natural antioxidants due to the presence of phenolic compounds, which are the secondary metabolites in plants (Misan 2010; Arya and Yadav 2011). Polyphenols, or phenolic compounds, constitute one of the most numerous and widely-distributed groups of substances in the plant kingdom (Urquiaga and Leighton 2000; Gan et al. 2010). They exist naturally in the form of glycosylated which makes them the most common water-soluble antioxidant compounds present in plants ...
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... antioxidant is effective for all stages (Jaswir et al. 2004). A combination of antioxidants in which the antioxidants produce a synergistic effect may be successful in inhibiting the lipid peroxidation. Recently, most of the studies have been focused on the antioxidant activity of the leaves crude extract and their individual polyphenols, only few studies have investigated the interaction of leaves crude extraction with other common antioxidants including α-tocopherol. Moreover, to date, there has been no scientific report of interaction between Aquilaria crassna young leaves crude extract and α-tocopherol. Therefore, in present study, agarwood leaves (Aquilaria crassna) crude extract are combined with α-tocopherol to investigate their antioxidant interaction against lipid peroxidation and to evaluate if the interaction promotes a synergistic antioxidant effect.
Strength The antioxidants are very strong. They are made very strong so that they don’t break or get ruined due to polymer oxidation in the
Rong, T., (2007). Extraction, Separation, Detection, and Antioxidant Activity of Apple Polyphenols. American Chemistry Society, Chapter 20, 302-324.
Anthocyanins, flavanols, flavanones,secoiridoids, phenolic acids, stilbenes, coumarins, and isoflavones form a large class of polyphenols, which are phenolic compounds. This study, however, focuses on one category of these phenolic compounds: phenolic acids. These particular compounds have been classified into two groups, namely hydroxycinnamic acids and hydroxybenzoic acids. The most common hydroxybenzoic acids are protocatechuic acid and gallic acid, while hydroxycinnamic acids include ferulic acid, coumaric acid, caffeic acid, chlorogenic acid, and sinapic acid, (Nigdikar, Williams, Griffin, & Howard). Unlike hydroxycinnamic acids, hydroxybenzoic acids usually occur at very low levels in some black radish, red fruits, and onions, accounting for about 10 ppm on a fresh weight basis. Protocatechuic ac...
Oxidative stress is essentially defined as the imbalance in the equilibrium of antioxidants systems in the human body. Oxidative damage in aerobic organisms can be caused by certain molecules known as reactive oxygen species (ROS). These reactive species are ones that cause oxidative damage in biomolecules. In order to maintain equilibrium of these substances, the human body has various endogenous antioxidants and phase 2 proteins which have evolved to defend against any harmful effects of ROS or any other reactive species. In normal physiological conditions, a balance is maintained between the ROS production and their detoxification by the appropriate antioxidants and phases 2 proteins. (Uttara, Singh, Zamboni & Mahajan, 2009). Oxidative stress can occur due too many pathological conditions, when the balance of prooxidants and antioxidants is disturbed oxidative damage could accumulate in proteins, lipids, carbohydrates and nucleic acids. In severe cases these events can lead to cell death. The process can directly alter the antioxidant systems by either inducing or inhibiting the proteins which take part in these systems. Moreover it can also cause the depletion of storage of antioxidants such as glutathione, vitamin E and many more in cells. (Thomas 2006). Antioxidants are defined as any substance which has the ability to inhibit, reduce or repair the damage as a result of an ROS in a biomolecule. The general three mechanisms that are used by antioxidants include the inhibition of ROS generation, the repair of damage induced by ROS and scavenging for ROS molecules. Since ROS plays a precarious role in both physiology and pathophysiology in the human body, it is vital that the endogenous antioxidants and phase prote...
Numerous epidemiological studies have shown that a diet high in vegetables and fruits is associated with reduced risk of most cancers [1,2]. Since ancient times, herbs and spices have been used for the treatment of various illnesses. They have been used to treat respiratory, gastrointestinal, rheumatic and inflammatory disorders. The beneficial effects of dietary phytochemicals such as curcumin (from turmeric), allicin (from garlic), and resveratrol (from grapes and peanuts) against inflammation and cancer only reinforce the importance of diet in controlling such chronic illnesses [3]. Cumin (Cuminum cyminum) is a spice, which is widely used in Asia and in the Middle East and has been used in traditional medicine to treat diarrhea, flatulence, and indigestion. An important use of cumin in Ayurveda, the traditional Indian medicine is to control inflammation in rheumatoid arthritis [4]. In this context, it is noteworthy that cumin extracts inhibit platelet aggregation by inhibiting the eicosanoid pathway of inflammatory mediator generation [5]. In an attempt to understand the spice’s biological properties, cumin was also shown to reverse chemically induced colon carcinogenesis in experimental animals [6,7]. The observed anti-carcinogenic activity appears to be due to the induction of both phase I and II detoxifying enzymes as well as inhibition of enzymes responsible for the reactivation of detoxified carcinogens [8]. Considering that tumorigenesis is a multistep process initiated and promoted by several factors including carcinogen activation and chronic inflammation, cumin fruits offer a potential source of anticancer compounds. While extensive chromatographic separation of the essential oils derived from cumin fruit was attempted...
Wine chemist Andrew L. Waterhouse told the SCIENCE News that even though many studies support the theory that antioxidants prevent heart diseases. It is still a mystery what in the blood or the low-density lipoproteins, which shuttle fat around in the blood, is slowing the oxidation. “In other words it may not be a direct effects of phenolics, but instead some indirect change that they trigger – such as altered fat or protein metabolism.”(Science News, Raloff) Recent studies have only suggested that it was the polyphenols that were causing the antioxidation but were never able to establish any kind of proof that it was the polyphenols that were causing the antioxidation, but they do initiate antioxidation that has often been proofed.
Flavanoids, carotenoids, phenols, sterols, quinones and sterols etc are the examples of phytochemicals. Sasi kumar et al., (2014) indicated the presence of alkaloids, flavanoids, saponins, carbohydrates, terpenoids, sterols and phenols in the ethanolic extract of coriander. Coumarins, steroids, tannins and sterols were present in the coriander (Tacouri et al., 2013). Methanolic, petroleum, chloroform, ethylacetate and aqueous extract indicated the presence of carbohydrates, reducing sugars and triterpenes where as glycosides and proteins presence was indicated only in the methanolic extract. Essential oil was absent only in the petroleum extract while others indicated the presence of essential oil (Pathak et al.,
In this study, a qualitative analysis of the phenolic composition has been carried out by HPLC-MS in negative and positive ionization modes from the hydro-methanol extract of R.coriaria fruits (Fig. 1). This method was used to identify and characterize of 191 phytochemical compounds (Matuszewski et al., 2003). Totally 78 hydrolysable tannins, 59flavonoid, 9 anthocyanin, 2 isoflavonoid, 2 terpenoid, 1 diterpene, 2 unknown whit C24H22O17 and C30H26O13 formulas in
Apples are great antioxidants. They prevent lipid peroxidation, which is degradation of fats in the organism under the influence of “free radicals”. This is particularly important for cardiovascular system protection.
The total phenolic content in extracts was measured by UV spectrophotometry based on a Colorimetric oxidation/reduction reaction. The oxidizing agent used was Folin-Ciocalteu reagent (AOCS,1990). To 0.2 ml of extract,7.5 ml water was added in a test tube and after that 0.5 ml of Folin-Ciocalteu reagent (diluted 2 times with water) was added and, then, 1 ml of Na2CO3 (40 %) were added. The sample was incubated for 30 min at room temperature . For a control sample, 0.2 ml of distilled water was used. The absorbance of the resulting blue-colored solutions was measured at 760 nm. Quantitative measurements were performed, based on a standard calibration curve of gallic acid in water. The results were expressed as gallic acid equivalents (GAE) in mg/g of
Antioxidants are chemicals that protect cells by neutralizing external forces (such as damage from the sun, pollution, wind, and temperature) and internal factors (for example, emotions, metabolism, and the presence of excess oxygen). Common antioxidants are Vitamins A, C, E, and beta carotene. These special chemicals assist in skin repair and the strengthening of blood vessels.
The leaves of local wild and cultivated plants are of vegetables which are rich in starch and part of African diet (Smith, 2007). Some of these African leafy vegetables can also be classified as functional foods because they contain high nutrient which are beneficial to human health (Van wyk, 2003). Green plants absorb the minerals they need for diverse anabolic processes from the soil, the complex organic compounds found in plant leaves are antioxidant molecules which serves as protection against oxidative solar radiation (Zimmermann, 2005). Leafy vegetables are therefore important sources of minerals, trace elements and photochemical with health protective and immune–strengthening properties. Molecular evidences shows that the trace elements in leafy vegetables and antioxidant molecules present lowers the risk of cancer and cardiovascular disease through a mechanism that molecule free radical attack on nucleic acids, proteins and polyunsaturated fatty acids (Borek,2003). This is an indication that leafy vegetables have a higher antioxidant properties compared to e...
Summary: Red wine is the one of the most common alcoholic drinks in many countries over the world. It contains the major polyphenol called Resveratrol (3,5,4’-trihydroxy-trans-stilbene) found mostly in skin of grapes that possess many health benefits. In nervous system, Resveratrol acts against Alzheimer’s disease as antioxidant. In circulatory system, Resveratrol acts as anti-atherogenic effect to improve lipid profiles. Immune system, Resveratrol acts as anti-inflammatory cytokines to suppress the inflammations. Moreover, Resveratrol acts as anti-cancer which can reduce the size of tumor growth and facilitate apoptosis. Resveratrol also helps in anti-aging, cytoprotective in renal, treatment of gastritis and improve retina remodeling. But
The phenolic compounds are the main component responsible for antioxidant activity, is mainly due to their redox properties, which can play an important role in absorbing and neutralizing free radicals, quenching singlet and triplet oxygen, or decomposing peroxides. Recently, phenolics or polyphenols have received considerable attention because of their physiological functions, including antioxidant, antimutagenic and antitumor activities. They have been reported to be a potential compound to combat free radicals, which are harmful to our body and foods systems (Nagai et al., 2003). Phenolic constituents are one of the major group of compounds acting as primary antioxidants especially as free radical terminators (Oviasogie et al., 1985; Ka, 1999). The level of antioxidants as evidenced in this study imply the presence of phenolics. Phenolic compounds comprise a large group of biological
“A preservative is a substance that is added to products such as foods, pharmaceuticals, paints, wood, beverages etc. to prevent decomposition by microbial growth or by undesirable chemical changes. In general preservation is implemented in two modes, chemical and physical.” The main function of preservation is to delay the spoiling of the food and to prevent any alterations in their taste or their appearance. There are different ways it could be done through preservation methods like canning, drying, smoking and freezing. However, the use of food additives such as antioxidants or other preservatives is what we will be focusing on. The reason number one for using preservatives on food is to make them safer to eat by erasing the effect of the biological factors. What the buyers are most worried about is the food getting spoiled or get molds/bacteria/yeast in them. This is because some of these organisms have toxins in them that can either be very dangerous to you or they can even kill you. But since most foods contain enzymes or natural chemicals, like acids or alcohols that causes them to lose appealing characteristics almost right after harvest or production. Food preservation normally has three goals that are: the preservation of nutritional