Chapter -4 Phytochemicals and Their Potentials Role in Prevent Diseases PDF

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Chapter - 4 Phytochemicals and Their Potentials Role in Prevent Diseases Author Chaudhary Shweta Research Scholar, Department of human development and family studies School for home sciences Babasaheb Bhimrao Ambedkar University (A Central University) Vidya Vihar, Raibareli road Lucknow, Uttar Prade...

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Chapter - 4 Phytochemicals and Their Potentials Role in Prevent Diseases

Author Chaudhary Shweta Research Scholar, Department of human development and family studies School for home sciences Babasaheb Bhimrao Ambedkar University (A Central University) Vidya Vihar, Raibareli road Lucknow, Uttar Pradesh India

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Chapter - 4 Phytochemicals and Their Potentials Role in Prevent Diseases Chaudhary Shweta

Abstract Phytochemicals mean “plant chemicals.” There are 1000 of various types of phytochemicals, present in vegetables, beans, fruits whole grains, and seeds. Eating significant exchange of plant foods items rich in phytochemicals in daily dietary intake may aid to prevent at least one in every five cases of cancer, in addition to other serious ailments such as cardiovascular diseases and various other lifestyle diseases. It is familiar that plants make these chemicals to save from harm themselves, but recent researches reveal that several phytochemicals can also save human against diseases. Keywords: Phytochemicals, dietary intake, lifestyle diseases 1.

Introduction

Phytochemicals derived from the Greek word phyto, meaning plant. They are organically active, naturally occurring chemical compounds present in plants, which gives health benefits for humans more than those endorsed to macronutrients and micronutrients [1]. The plants are protected by phytochemicals from disease and damage and they also give to the plant’s aroma, color and flavor. In common, the plant chemicals that save plant cells from ecological hazards such as stress, drought, pollution, UV exposure and pathogenic attack are called as phytochemicals [2, 3]. Recently, it is evidently acknowledged that they play vital roles in the defense of human being health too, when they are included in dietary intake with recommended amount. There are more than four thousand phytochemicals have been classified [4] and are also classified by defensive function, physical uniqueness and chemical individuality [5]. There are some common sources of dietary phytochemicals are found in Page | 65

edible part of plant like stem, roots, flower, leaves, legumes, whole grain, seed, nut, vegetables, fruits, fungi, spices and herb, broccoli, carrots, cabbage, onions, garlic, whole wheat bread, tomato, cherries, grapes, strawberries, beans, soy food, raspberries etc. In the external of the various plant tissue many types of phytochemical (pigment molecules) are rarely concentrated. These levels may vary depending on the growing condition, variety of plants etc. from plant to plant [8] . These compounds are called as secondary plant metabolites and have different biological characterstics like anticancer property, decrease of platelets aggregation, antioxidant activity, modulation of detoxification enzymes, modulation of hormone metabolism antimicrobial effect and stimulation of the immune system. Now it is well known that plants yields these chemicals to save themselves [9], but recently researches reveals that many phytochemicals also provide protection, prevention and treatment against various human diseases. 2.

Biological Activities of Phytochemicals: In the above biological context of phytochemicals there is a requirement of study to understand the basic principle of mechanism of their action. These studies have included establishment of their biological potency both by in vivo and in vitro, identification and isolation of chemical component studies in experimental animals.

Study result suggested that phytochemicals may decreases the chance of coronary heart diseases by preventing the oxidation of low density lipoprotein (LDL) cholesterol, minimizing the synthesis or absorption of cholesterol, normalizing blood clotting and blood pressure, enhancing arterial elasticity [3, 13]. Phytochemicals also detoxify substances that leads to the cause of cancer. They appear to make ineffective free redicals block the enzymes that makes active carcinogens and also make active enzymes that detoxify carcinogens. For example as per data summarized by Thomson and Meagher, genistein stops the formation of new capillaries that are required for tumor growth and metastasis [5]. Phytochemicals have also been encouraging for the treatment and prevention of diabetes, muscle degeneration and high blood pressure [4]. [See table [1].

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Table 1: Bioactive Phytochemicls in Medicinal Plants

Source: www.phytojournal.com, ISSN 2278- 4136 ZDB-Number: 2668735-5 IC Journal No: 8192 volume 1 issue 6 Page | 170,

3.

Classification, Structure and Role of Phytochemicals: Depending on their mode of action in plants metabolisms phytochemicals are categorized as primary and secondary components.

Primary components includes common sugar, amino acids, proteins, chlorophyll, pyrimidines and purines of nucleic acids etc. Secondary components are the remaining plant chemicals such as flavonoid, alkaloids, lignans, terpenes, curcumines, saponins, plant steroids, glucosides, phenolics and flavonoids [14]. 3.1 Phenolics: Phenolics phytochemicals are the broad class of phytochemicals and also mostly distributed in the plant kingdom. Phenolics compounds are huge and complex group of chemical components present in plants [15]. The three chief groups of dietary phenolics are flavonoids, phenolics acids and polyphenols. They involves in plant secondary metabolism process. They also play a significant role as defense compounds as an antioxidants properties helpful to human in helping their role I providing protection against free- radicals mediated diseases process. Phenolics are hydroxyl group (OH) having unit of chemical compound where (-OH) directly bounded to an group of aromatic hydrocarbon [16]. Flavonoid are the different group of plant chemical present in widely in all the fruits and vegetables. As per Global Healing Center, they are related with skin protection, function of brain, blood pressure regulation, diabetes. They are naturally active and water soluble plant nutrient. Page | 67

3.2 Phenolic Acids: The group that have the hydroxybenzoic and hydroxycinnamic acid, its polymers known as tannins. Tannins have high molecular weight and are of two types hydrolizable and condensed tannins. Their properties are chief in determining their role as defensive agents against free radical-mediated diseases course of action. Phenolics acid in common dominants phenols that contain one carboxylic acid functional group. The two different carbon frameworks: the hydroxycinnamic and hydroxybenzoic structures. Hydroxycinnamic acid compounds created as simple ester with glucose or hydroxyl carboxylic acids. Plant phenolic constituents are different in molecular structure and are characterized by hydroxylated aromatic rings. They have properties against oxidative damage which leads to several degenerative diseases like cancer, cardiovascular and inflammation [17]. [See in table [2].

Source: dx.doi.org/10.1021/jf200591d |J. Agric. Food Chem.2011, 59, 4331–4348

The cells which have greater level of reactive oxygen species (ROS) like tumor cells along with leukemia cell than normal cells therefore they are especially sensitive to oxidative stress [18]. Page | 68

In recent year the significance of antioxidant properties of phenolic constituent and their use as a natural antioxidant agent in processed foods has occupied a new level [20]. 3.1.a Activity of Phenolic Acids: Phenolic compounds are common groups in secondary metabolism process of plant with large pharmacological properties. These get polymerized into molecules like proanthocyanidins (PA; Condensed tannins) and lignins. Phenolic acids found in edible plants as glycosides or ester with other natural constituents such as alcohols, hydroxy fatty acids, sterols and glucosides. The various biological activities of phenolic acids are increase secretion of bile, reduction in blood cholesterol and lipid level and antimicrobial property. Phenolic acid attributed different biological properties for example antiulcer, antidepressant activities, antitumor, anti-inflammatory, antispasmodic, antioxidant and cytotoxic [22, 23]. 3.3 Flavonoids: Flavonoids played a key function in fruitful medical treatments. Flavonoids are found in vascular plants as methylated derivatives, aglycones and glucosides. Common sources of flavonoids are fruits, vegetables and beverages like tea, coffee and fruit drinks [24, 25]. Small portion of aglycones (sugarless flavonoids) are often present and rarely represent a considerably main ratio of the total flavonoid compounds in the plants. The six- membered ring strong with the benzene ring is either pyrone (flavones and flavonols) or its dihydro derivative (flavanones and flavan-3-ols). The flavonoid are of two types depending on the place of the benzenoid substituent flavones (2 position) and isoflavone (3 position). The majority of flavonoids found naturally associated with sugar in conjugated form and, within any one class, may be characterized as monoglycosidic, diglycosidic, etc. The glycosidic linkage is normally located at position 3 or 7 and the carbohydrate unit can be L-rhamnose, Dglucose, glucorhamnose, galactose or arabinose [26]. 3.3.a Activity of Flavonoids: Flavonoids have gained recent consideration because of their broad biological and pharmacological activities in these order. Flavonoid have been reported to use many biological characteristic including anti-inflamatory, antimicrobial, cytotoxicity as well as antitumor activities. The position of hydroxyl groups and other features in the chemical

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structure of flavonoid are important for their antioxidant and free radical scavenging activities. On the other hand flavonoids like cathechins, are better antioxidants than the nutrients antioxidants such as vitamins E, beta carotene and vitamins c. Flavonoids play many helpful role anti-inflammatory activity, enzyme inhibition, oestrogenic activity, antimicrobial activity, anti-allergic activity, cytotoxic antitumor activity, antioxidant activity and vascular activity [27]. Flavonoids comprise a wide range of substances that play vital role in protecting biological process against injurious effects of oxidative processes on macromolecules, like lipid, carbohydrate, proteins and DNA [28]. 3.4 Tannins: Tannins (tannoids) are a form of astringent, polyphenolic biomolecule that bind and precipitate proteins and various other organic component. The term tannins derived from tanna which means bark or fir tree. On the basis of structural characterstics it is divided into 4 major categories; Gallotannis, complex tannins, condensed tannins and ellagitannins [34, 35, 36]. 1.

Gallotannins-Those tannins in which galloyl units or their metadepsidic derivatives are bound to diverse polyol-, cathechin-, or triterpenoid units.

2.

Ellagitannins–Those tannins in which at least two galloyl units are C-C coupled to each other & donot have a glycosidically linked cathechin unit.

3.

Complex tannins–are tannins in which a cathechin unit is bound glycosidically to a gallotannin or an ellagitannin unit.

4.

Condensed tannins-All oliogomeric and polymeric proanthocyanidins formed by linkage of C-4 of 1 cathechin with C8 or C-6 of the next monomeric cathechin.

5.

Dietary sources of tannins are chocolate, grapes, blueberry, persimmom, tea, legume trees like sesbania Spp. Acacia spp., in grasses like corn, sorghum [37].

3.4.a Activity of Tannins: Tannins act as a natural healing, the plant extracts containing tannin are used as astringents against stomach & duodenal tumors, diarrhea, as diuretics [39]. And also as antiinflammatory, antiseptics, antioxidant, and haemostatics [40] pharmaceuticals .

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Several health advantages have been familiar for the intake of tannins with the decreased frequency of chronic diseases have been recognized [38]. 3.4.b Industrial Uses of Tannins: Tannins are used as a dyestuff caustics for cationic dyes (tannins dye), used in the production of inks (iron gallate ink) in textile industries. In the food industry tannins are used as a clarifying agent and antioxidant in fruit juices, wine and beer. And also as coagulants in rubber production [41]. Recently tannins draws interests of Scientist especially due to the high incidences of deadly diseases like AIDS & many types of cancers. The search for a new lead component has become increasingly important for the advancement and development of novel pharmaceuticals, especially as the biological activity of plant extracts containing tannins has been well recognized [43, 44]. 3.5 Alkaloids: The bionutrient which contains hetrocyclic nitrogen atoms are basic in natural. As the term is derived from alkaline means any nitrogen containing base [45]. They are naturally synthesis by a large number of organisms including animals, plant, bacteria and fungi. In the beginning year of 19 centuary alkaloids are first obtained from plants material (isolation from medicinal plant) and also it was found that they were containing nitrogen bases which formed salts with acid. Therefore they were also known as vegetable alkaloids and these are also used as the local anesthetic and stimulants as cocaine [46]. Due to the presence of quinine (bitterest tasting substances, bitter at 1x 10 at a molar concentration) in the alkaloids [47]. -5

The names of individual membrane generally drived from the name of the plant in which they occur, or from their characterstics physiological activity the various classes of alkaloid on the basis of the hetrocyclic ring system they contain are as follows: 1.

Pyrrolidine Alkaloids: They have pyrrolidine (tetrahydropyrrole) ring system. E.g Hygrine found in Erythroxylum coca leaves.

2.

Pyridine alkaloids: they have piperidine (hexahydropyridine) ring system. E.g Coniine, piperine and isopelletierine.

3.

Pyrrolidine-Pyridine Alkaloids: The heterocyclic ring system present in there alkaloids is Pyrrolidinepyridine. E.g Myosmine, Nicotine alkaloid found in tobacco (Nicotiana tabacum) plant.

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4.

Pyridine-Piperidine Alkaloids: This family of alkaloids contains a pyridine ring system join to a piperidine ring system the simplest member is Anabasine alkaloid isolated from poisonous Asiatic plant anabasis aphyllan.

5.

Quinoline Alkaloids: These have the basic heterocyclic ring system quinoline. E.g Quinine occurs in the bark of cinchona tree.It has been used for centuries for treatment of malaria. Synthetic drugs such as primaquinine have largely replace quinine as an antimalarial.

6.

Isoquinoline Alkaloids: They contain heterocyclic rig system isoquinoline. E.g Opium alkaloids like narcotine, papaverine, morphine, codeine, and heroine.

3.5.a Activity of Alkaloids- Alkaloids provides protection and survival of plant because they ensure their survival against antibacterial and antifungal activities, insects and herbivorous and also against other plants by means of allelopathically active chemicals [49]. Alkaloids have various medicinal activities like antihypertensive effects (many indole alkaloids), antiarrhythmic effect (quinidine, spareien), anticancer actions (dimeric indoles, vincristine, vinblastine) antihypertensive effects (many indole alkaloids) and antimalarial activity (quinine). The alkaloid containing plant used as dyes, spices, drugs. These are few example illustrating the great economic important of this class of plant constituent [50]. Some alkaloids have stimulation property like caffeine and nicotine morphine. Quinine used as the antimalarial drug and morphine are used as the analgesic [46]. 3.6 Terpenoids: The terpenoids are a class of natural products, derived from 5-carbon isoprene units. Most of the terpenoids have multicyclic structures that vary from one another by their functional groups and basic carbon skeletons.These kind of natural lipids can be found in almost every class of living things that is why it is also considered as the largest group of natural product [51]. 3.6.a Commercial use of Terpenoid: Commercial use of terpenoid as flavouring agents and adds fragrances in the food and cosmetics (menthol and sclareol). They are also important for quality of agricultural product like flavour of fruits and fragrance of flavor (linalool) [52]. Terpenes are mainly present in nature as constituents of essential oils in Page | 72

plants. Terpenes hydrocarbons have molecular formula (C5H8)n. The hydrocarbon isoprene is the building blocks of terpenes. They are classified according to the no. of isoprene unit. [53] 1.

Hemiterpenoids: Contain a single isoprene unit and it is the only hemiterpene which is the Isoprene itself, but oxygen-containing derivatives of isoprene such as isovaleric acid and prenol is classify as hemiterpenoids.

2.

Monoterpenoids: Biochemical modifications of monoterpenes such as oxidation or rearrangement produce the related monoterpenoids. Monoterpenoids have two isoprene units. Monoterpenes may be of two types i.e linear (acyclic) or contain rings e.g. Geranyl pyrophosphate, Eucalyptol, Limonene, Citral, Camphor and Pinene.

3.

Sesquiterpenes: Sesquiterpenes have three isoprene units e.g. Artemisinin, Bisabolol and Fernesol, oil of flowers, or as cyclic compounds, such as Eudesmol, found in Eucalyptus oil.

4.

Diterpenes: It consist for four isoprene units. They derive from geranylgeranyl pyrophosphate. There are some examples of diterpenes such as taxadiene and cafestol, kahweol, Retinol, retinal, cembrene, and phytol are the biologically important compounds while using diterpenes as the base.

5.

Triterpenes: It consists of six isoprene units e.g. Lanosterol and squalene found in wheat germ, and olives.

6.

Tetraterpenoids: It contains eight isoprene units which may be acyclic like lycopene, monocyclic like gamma-carotene, and bicyclic like alpha- and betacarotenes.

3.1.b Activity of Terpenes Among plant secondary metabolites terpenoids are a structurally large varied group; they function as phytoalexins in plant direct defense, or as signals in indirect defense responses which involves herbivores and their natural enemies [54]. Terpenes play an important role as signal compounds and growth regulators (phytohormones) of plants, as shown by introductory investigations. In addition, terpenoids can have medicinal properties such as antimalarial (e.g. artemisinin), anti-ulcer, hepaticidal, antimicrobial or diuretic (e.g. glycyrrhizin) activity, anticarcinogenic (e.g. perilla alcohol), and the sesquiterpenoid antimalarial drug artimisinin and the diterpenoid anticancer drug taxol [53, 56]. Page | 73

3.7 Saponin Saponins are a set of secondary metabolites found broadly distributed in the plant kingdom they form a stable foam in aqueous solutions such as soap, hence the name “saponin”. Chemically, saponins as a group include compounds that are glycosylated steroids, triterpenoids, and steroid alkaloids. Two main types of steroid aglycones are known, spirostan and furostan derivatives. The main triterpene aglycone is a derivative of oleanane [57] . The carbohydrate part consists of one or mo...