Bioactive Components from Natural Sources

Identification of Bioactive Components from Natural Sources 

Jayaprakasha and Bhimanagouda S. Patil Vegetable Fruit Improvement Centre, Department of Horticultural Sciences, Texas A M University, 

The most important natural sources of flavors are the essential oils derived from spices, fruits, and flowers as well as extractives and exudates (resins) from certain plant sources and animal secretions, e.g., musk. Essential oils are aromatic substances which are widely used in several industries such as perfume, pharmaceutical, food, and nutrition. These are mixtures of more than 200 compounds [14,16]. It contains monoterpenes, sesquiterpene hydrocarbons, and their oxygenated derivatives, along with aliphatic and aromatic aldehydes, alcohols, esters, and nonvolatile residues. Generally, terpenes are unsaturated com- 

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IDENTIFICATION OF BIOACTIVE COMPONENTS FROM NATURAL SOURCES... 

The development of health-promoting foods is likely to entail increasing use of different protein sources known to contain bioactive components. They may be natural constituents of plant or animal origin, or genetically modified or transferred from another source. It is likely that, in the future, more and more traditional food products will appear on the market, containing... 

The term nutraceutical, coined in 1989 by Stephen DeFelice, arises from combination of two words, nutrition and pharmaceutical, and defines food or food products that can provide medical and health benefits, including prevention and treatment of disease. Whole grains, beans, and herbs are known to include natural products with therapeutic potential, but fruits and vegetables are their main natural source. Edible mushrooms have also been reported to have medicinal properties [8,9]. Fortified foods, dietary supplements, herbal products, genetically engineered foods, and processed products such as cereals, soups, and beverages are considered nutraceuticals, even when in most cases bioactive components have not been scientifically standardized [10]. 

Among computational approaches that can help driving the discovery of new bioactive compounds, a prominent workflow is the screening of large database of readily available molecules. It is with surprise that the scientific community has not developed yet a freely available and fully chemically annotated database of food components [8, 9], Despite this lack, some examples are starting to appear in the literature and on the Internet. Among them, we can list the INFOODS of FAO [129], the USDA national nutrient database [130] and the FooDB that has been recently released [131]. In the direction of the creation of a comprehensive and freely available collection of food chemicals, it should be noted also the necessity to include the possible procurement from commercial sources of purified samples of food components that, ideally, should complement the major efforts that have been done in the past years for other natural sources [123]. 

Tlie NMR spectrum (300 MHz in D2O/H2O (1 5), TSP (trimetliysilyl-2,2,3,3-tetradeuteropropionic acid sodium salt) = 0.00 p.p.m.) of toxin 1 was simple 5 2.16 (t, / = 1.5 Hz, IH) and 7.09 (d, / = 1.5 Hz, 2H) (Supplementary Fig. 1 online). Its NMR spectrum (75 MHz in D2O/H2O (1 5), TSP = -2.00 p.p.m.) indicated three types of carbon atoms at 5 17.03, 103.89 and 183.16 p.p.m. (Supplementary Fig. 2 online). Its molecular mass [M]" " by HREI-MS m/z) was 84.0211, which corresponds to C4H4O2 (84.0211). Tliese data indicate that the toxin is cycloprop-2-ene carboxylic acid (1) (Fig. la. Supplementary Methods and Supplementaiy Figs. 3 and 4 online), which is a known syndietic compound that has never been isolated from a natural source. Cycloprop-2-ene carboxylic acid appears to be the smallest carboxylic acid with strong lethal toxicity. Cyclopropenes are versatile components for synthetic organic chemistry. In addition, some bioactive cyclopropenes have been reported... 

In search of bioactive substances, researchers have directed their interest towards substances found in plants. Parts of plants which have been used in natural medicine have proved to be a rich source of bioactive compounds however, to make use of them, they have to be isolated and their properties deterrnined. Using selective techniques of extraction has resulted in obtaining concentrated preparations of bioactive substances. To achieve comprehensive knowledge of their properties, it was necessary to develop methods of isolation of individual components and testing these methods. This could be done with chromatographic techniques. Isolated compounds were tested in order to show which of them (and to what extent) are responsible for bioactivity of plant preparations from which they were obtained. Due to the fact that many of the substances have the opposite effect, it is frequently impossible to use extracts without isolating individual compounds. 

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