Sugarcane juice rich with antioxidants

Sugarcane (Saccharum officinarum L.) juice is widely consumed by people of the tropics and subtropics.

The objective of sugarcane harvest is to produce sugarcane stalks with the highest possible sucrose content, ranging from 10 to 15% of the weight of stalks. Most sucrose is stored in the inner portion of the stalks while majority of valuable sugarcane extracts, including antioxidants, concentrate in the outer component (rind fraction) of the stalks.

Sugarcane juice also contains high levels of antioxidants like flavonoids and polyphenolic compounds, which can help reduce oxidative stress and improve human overall health.

Pigments in sugarcane juice are mainly phenolic compounds. The main compounds phenolic composition in sugarcane and its products were phenylpropanoids and flavonoids.

Study on sugarcane extract has displayed a wide range of biological effects including immunostimulation, anti-thrombosis activity, anti-inflammatory activity, vaccine adjuvant, modulation of acetylcholine release and anti-stress effects. Sugarcane juice has broad biological effects in raising innate immunity to infections.

There are thirteen antioxidant compounds have been identified, including several glycosylated phenolic compounds in kokuto (brown sugar of sugar cane in Japan). Some identified compounds exhibited higher antioxidant activity than αtocopherol.

Study indicate that the sugarcane juice of different varieties was effective in giving antioxidant protection at various levels, inhibition of radical formation (by reducing iron complexes), radical scavenging at both primary and secondary stages, and in membrane protection (as assayed by lipid peroxidation). The mechanism involved in many human diseases such as hepatotoxicoties, hepatocarcinogenesis, diabetes, malaria, acute myocardial infarcation, skin cancer includes lipid peroxidation as a main source of membrane damage.
Sugarcane juice rich with antioxidants 

Classification of antioxidants – based on the functions

An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Antioxidants are a class of chemical substances naturally found in food which can prevent or reduce the oxidative stress of the physiological system. Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, unstable molecules that the body produces as a reaction to environmental and other pressures.

Free radicals may play a role in heart disease, cancer and other diseases. Antioxidants, such as vitamins C and E and carotenoids, may help protect cells from damage caused by free radicals. Other naturally occurring antioxidants include flavonoids, tannins, phenols and lignans.

There are different attributes to classify the antioxidants. The first attribute is that antioxidants can be divided into three groups by their mechanism/functions: Primary antioxidants are involved in the prevention of oxidant formation; secondary antioxidants are known to be scavengers of ROS (Reactive oxygen species). and tertiary antioxidants, which are concerned with the repair of damaged biomolecules.

The second attribute is based on enzymatic and non-enzymatic antioxidants.

Primary antioxidants (Free radicals scavengers)
Primary antioxidant can accept free radicals and further delay the initiation step or interrupt the propagation step of auto-oxidation. Primary antioxidants can react with lipid and peroxyl radicals converting them into more stable radicals or non radical products.

They are the chain breaking antioxidants which react with lipid radicals and convert them into more stable products.

Primary or natural antioxidants can be extracted from plants, microorganisms and animal tissues. Antioxidants of this group are mainly phenolics, in structure and include the following: antioxidant minerals, antioxidant vitamins and phytochemicals which include flavonoides, catechins, carotenoids, β-carotene, lycopene, diterpene of, black pepper, thyme, garlic, cumin and their derivatives.

They are very effective radical scavengers during both processing and long-term thermal aging, and are generally non-discoloring.

Secondary antioxidants
These are phenolic compounds that perform the function of capturing free radicals and stopping the chain reactions. They react with hydroperoxides to yield non-radical, non-reactive products. They are compounds produced artificially and added to processed or pre -packaged food to prevent rancidity, browning.

Secondary antioxidants retard oxidation by preventing the proliferation of alkoxy and hydroxyl radicals by decomposing hydroperoxides to yield nonreactive products. Secondary antioxidants can retard lipid oxidation through a variety of mechanisms, including chelating of transition metal ions, oxygen scavenging, replenishing hydrogen to primary antioxidants, absorbing UV radiation and deactivation of reactive species.

The compounds include: Butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT) and propyl gallate (PG).
Classification of antioxidants – based on the functions

Antioxidant activity

Antioxidant means "against oxidation”. Antioxidants are compounds capable to either delay or inhibit the oxidation processes which occur under the influence of atmospheric oxygen or reactive oxygen species. They are used for the stabilization of polymeric products, of petrochemicals, foodstuffs, cosmetics and pharmaceuticals.

Antioxidants are considered as important bioactive compounds on account of many health benefits along with their pivotal role in delaying oxidative rancidity of numerous foods. They protect the key cell components by neutralizing the damaging effects of free radicals, which are natural byproducts of cell metabolism

Oxidation reaction depending upon site of occurrences presents specific repercussions. If the site of occurrence is food system, then food deteriorates. When oxidation occurs in biological cell system, it causes damage or death to the cell.

Oxidation is a chemical reaction that transfers electron or hydrogen from substances to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions, when the chain reactions occur in a cell, it can cause damage or death to the cell.

The oxidative deterioration of fats and oils, when present as a component in foods, is responsible for rancid odor and flavor with a consequent decrease in nutritional quality, sensory appeal and safety.

This is caused by the formation of primary hydroperoxides and secondary potentially toxic compounds through auto-oxidation of unsaturated fatty acids consisting of a free radical chain mechanism.

Fruit juices, beverages and hot drinks contain high amounts of antioxidants, like polyphenols, vitamin C, vitamin E, Maillard reaction products, β-carotene, and lycopene. The consumption of fruit juices, beverages and hot drinks was found to reduce the morbidity and mortality caused by degenerative diseases.

Various factors which affect the efficiency of antioxidants include activation energy of antioxidants, redox potential stability of pH and processing and stability.
Antioxidant activity

Category of antioxidant based on solubility

Antioxidants are a class of chemical substances naturally found in food that can inhibit the formation and spread of free radicals which can be damaging in biological systems. Free radical damage may lead to cancer. Examples of antioxidants include vitamin C, vitamin E, α-carotene, licopein, selenium, polyphenol, glutathione, proxidase, cystine.

Based on their solubility, antioxidants are categorized into two groups:
*Water soluble
*Lipid soluble.

Water-soluble antioxidants, such as ascorbic acid, glutathione, and uric acid, have functions in the cell cytosol and the blood plasma.

The lipid-soluble antioxidants including vitamin E, ubiquinol and carotenoids are the examples of lipid soluble antioxidants and protect the cell membranes from lipid peroxidation. Total lipid-soluble antioxidant activity was highest in mucosa from the duodenum followed by the jejunum, with much lower activities in the ileum, ceca and colon.

Fruit juices, beverages and hot drinks are rich of antioxidants, such as polyphenols, vitamin C, vitamin E, Maillard reaction products, β -carotene, and lycopene. β - carotene can be found in many foods that are orange in color. This include sweet potatoes, carrots, cantaloupe, squash, apricots, pumpkin and mangoes.  
Category of antioxidant based on solubility

Fruits and vegetables with antioxidants compounds

Food oxidation regularly causes a decrease in consumer acceptance, but in some cases, oxidative reactions of specific food components lead to an improvement in the product quality.

Antioxidants are compounds that can delay or inhibit the oxidation of lipids, nucleic acids or other molecules by inhibiting the initiation or propagation of oxidizing chain reactions.

Fruits showed a remarkably high scavenging activity of chemically generated active oxygen species. The range of hydrophilic antioxidant capacities was large among the different fruits such as prunes, raisins, blackberries, blackcurrants, blueberries, raspberries, strawberries, grapes, pomegranates and some varieties of apples.

Many natural products such as plant phenolic compounds, spice extracts, amino acids, and proteins have significant antioxidant activity. Food processing may also result in the formation of antioxidant compounds such as Maillard reaction products.

Antioxidants such as vitamin C is found in many fruits and vegetables,; vitamin E in grains and vitamin A in yellow vegetables like squash. Many nuts and seeds contain the minerals selenium and zinc.  
Fruits and vegetables with antioxidants compounds

Natural antioxidants

Antioxidants have been described as “substance that, when present at low concentrations compared with those of an oxidizable substrate, significantly retards oxidation of that substrate”.

The antioxidants may be classed as natural and synthetic. Many fats and oils, particularly in the unrefined form, are quite stable to oxidative rancidity because they contain natural antioxidants.

It has generally been shown that antioxidants compounds from plants are phenolic in nature and encompass such groups of compounds as tocopherols, carotenoids, phenolic acids, flavonoids and diterpenes. The tocopherols (α, β and γ) are the most important of the natural antioxidants and are widespread in both plant and animal tissues.

α- tocopherols

Natural antioxidants, mostly absorb light in the UV region (100-400 nm), can effectively scavenge free radicals, and chelate transition metals, thus stopping progressive autoxidative damage and production of off-odors and off-tastes in food products.
Natural antioxidants

What are antioxidants?

A biological antioxidant is a compound that protects biological systems against the potentially harmful effects of processes or reactions that cause excessive oxidation.

Although oxidation is an important process for sustaining life, it produces free radicals (‘hydroxyl radical’ or ‘superoxide anion’ or ‘hydrogen peroxide’), which cause chain reactions in the body that eventually damage the cells. Antioxidant can prevent this destructive oxidation of other molecules in the body.

Antioxidants stop the chain reaction by removing the free radicals and by stopping other oxidation reactions.

Antioxidants are found naturally in many foods, primarily fruits and vegetables. They are also available as supplements.

Hydrophilic compounds, such as vitamin C, thiols, and flavonoids, as well as lipophilic compounds such as vitamin E, vitamin A, carotenoids, and ubiquinols, are the best-known natural antioxidants.

Some minerals, such as selenium are also considered to have antioxidant properties. Many studies report benefits of antioxidants in preventing heart disease, neurological diseases, macular degeneration and even some cancers.
What are antioxidants?

Health benefits of ellagic acid

Ellagic acid is a dimeric derivative of gallic acid also known as hexahydroxydiphenic acid, which spontaneously forms a dilactone.

It is the lactone form that is commonly known as ellagic acid. This acid is already present in most ellagitannin-rich foods and is also produced during food processing and storage.

Ellagitannin present as the structural components of the plant cell wall and cell membrane. Ellagic acid and its derivative have limited distribution.

They are first seen at high concentrations in the strawberries, raspberries, cranberries, blackberries and grapes. Other sources of ellagic acid include walnuts, pecans and distilled beverages.

Recent studies indicated that ellagic acid possesses anti-mutagenic, antioxidant and anti-inflammatory activity in bacterial and mammalian systems.

Ellagic acid has been shown in research and laboratory models to inhibit the growth of tumors caused by certain carcinogens. It causes apoptosis of cancer cells in the lab, within no change to healthy, normal cells.
Health benefits of ellagic acid

Contribution of Fruits to Human Nutrition

Contribution of Fruits to Human Nutrition
Fruits are not only colorful and flavorful components of our diet, but they also serve as a source of energy, vitamins, minerals and dietary fiber.

The U.S department of Agriculture Dietary Guidelines encourage consumers to enjoy “five a day,” eat at least two servings of fruit and three servings of vegetables each day and to choose fresh, frozen, dried or canned forms of a variety of colors and kinds of fruits and vegetables.

In some countries, consumers are encouraged to eat up to 10 servings of fruits and vegetables per day.

ENERGY (Calories)

• Carbohydrates: banana, breadfruit, jackfruit, plantain, dates, prunes, raisin

• Proteins and amino acids: nuts, dried apricot, fig

• Fats: avocado, olive, nuts

VITAMINS
Fresh fruits and vegetables contribute about 91% of vitamin C, 48% of vitamin A, 27% of vitamin B6, 17% if thiamin and 15% of niacin to the U.S diet.

• Vitamin A: apricot, peach, cherry, orange, mango, papaya, persimmon, pineapple, cantaloupe, watermelon

• Vitamin C: strawberry, orange, grapefruit, kiwifruit, pineapple, banana apple, cantaloupe

• Niacin: peach, banana, orange, apricot

• Riboflavin: banana, [peach, orange, apple, avocado

• Thiamin: orange, banana, grapefruit, apple

MINERALS
Fresh fruits and vegetables contribute about 26% of the magnesium and 19% of the iron to the U.S diet
The following fruits are important contributors to the supply of indicated minerals in the U.S diet

• Potassium: banana, peach, orange, apple, dried fruits such as apricot and prune

• Phosphorus: banana, orange, peach, fig, raisin

• Calcium: tangerine, grapefruit, orange

• Iron: strawberry, banana, apple, orange

DIETARY FIBER

• All fruits and nuts contribute to dietary fiber. Dietary fiber consists of cellulose, hemicellulose, lignin and pectic substances, which are derived primarily form fruit cell walls and skin.

• The dietary fiber content of fruits ranges from 0.5 to 1.5% (fresh weight)

• Dietary fiber plays an important role in relieving constipation by increasing water holding capacity of feces. Its consumption is also linked to decreased incidence of cardiovascular disease, diverticulosis, and colon cancer.

ANTIOXIDANTS
Fruits, nuts, and vegetables in the daily diet have been strongly associated with reduced risk for some forms of cancer, heart disease, stroke and other chronic disease. This is attributed, in part, to their content of antioxidant phytochemicals.

• Red, blue, and purple fruits (such as apple, blackberry, blueberry, blood orange, cranberry, grape, nectarine, peach, plum, prune, pomegranate, raspberry, and strawberry) are good sources of flavonoids and other phenolic compounds that are positively correlated with antioxidant capacity of the fruit.

• Orange-flesh fruits (such as apricot, cantaloupe, mango, nectarine, orange, papaya, peach, persimmon and pineapple) and some red flesh fruits (such as tomato, watermelon and pink grapefruit) are good sources of carotenoids. Availability of lycopene to human is increased during tomato processing.

Contribution of Fruits to Human Nutrition