RICERCA ITALIANA     

Natural products with antioxidant activity from plants

Università degli Studi di Napoli "Federico II"

Abstract

Some components in edible plants and in beverages are in the center of scientific debate for their potential positive effects for healt benefits. These compounds are named nutraceuticals and possess a wide range of biological activities and, parallely working with biosynthetic pathway, shown antioxidant and cytoprotective activity with a sensitive reduction of human chronic degenerative diseases.
The research project will be carried out in four phases and is focused to determination of new compounds with antioxidant activity starting from plants extracts such as : grapes, food plants and vegetable species, very common and few studied, coming from Valsesia and from Center of Italy. This project came together and coordinates the programs of four research units with different specific background in the field of botany, biology, chemistry and analysis of antioxidant activity that will be performed though specific tests.
The FIRST PHASE of this project involves an expert botanist for the selection, collection and taxonomic identification of vegetable species coming from Valsesia and from Center of Italy. Crude extracts of each species will be prepared and a preliminary screening will be performed. Perugia research unit will provide to literature screening for the antioxidant activity.
The SECOND PHASE of the project will concern the isolation and structural elucidation of bioactive components with positive results. Along with the study of Valsesia plants >>>

Principal Investigator

Franco ZOLLO Università degli Studi di NAPOLI "Federico II"

Research Objectives

The program is based on the chemical characterization of secondary metabolites with antioxidant activity from plants. Attention will be focused on grapes, on plants commonly used as a food and on plants, very common and few studied, coming from Valsesia and from central Italy.
The research units, participating to the project, possess a specific background in the fields of chemistry, biology and pharmaceutical botany and the project will be articulated in 4 phases as follows (each step is described in the section 2.4 of this research program) :


Fhase 1

Selection and collection of vegetal species from different geographical areas will include areas that differ greatly for climatic and geo-pedological characteristics of central Italy and Valsesia

Fhase 2.

- Chemical studies on active extracts in preliminary tests: isolation and structural characterization by spectroscopic techniques (NMR, IR, UV, MS).

- Extraction and structural characterization of polyphenolic metabolites from grapes with antioxidant activity: analysis of complex mixture of procyanidines from grapes by modern and sophisticated chromatographic methodologies.

Phases 3.

- Determination of antioxidant activities of pure metabolited isolated from different vegetal species.

Phases 4.

- Development of clones with the same characteristics of productivity as the >>>

First Results

The predicted partial resuls are:

- Complete the collection of information concerning the traditional use and the presence of officinal plants in Valsesia

- Collection and taxonomic identification of the species coming from Valsesia, with the aid of an expert botanist operating in loco.

- Establishment of the herbarium.

- Preparation of extracts with increasing polarity solvents.

- Preliminary screening of biological activity on the raw extracts of the species collected in Valsesia and central Italy.

- Shipment of the biologically active fractions to the units in charge of the analysis, and identification of the active metabolites.The predicted partial resuls are:


- Isolation and structural characterization of compounds with antioxidant activity from food plants. Our attention will be devoted to food species used as spices or flavours such as Capsicum, Laurus nobilis, Foeniculum vulgaris, Juniperus communis and some species of Labiate family.

- Stereochemical determination of pure compounds by NMR (NOESY and ROESY experiments) and chemical approaches.Evaluation of antioxidant activity of metaboliets isolated and structural characterizated by research units involved in the phase 2.The predicted partial resuls are:


- Chemical analyses on the clones obtained to determine whether the original phytochemical characteristics have >>>

Timescale

24 months

National and international background

One of the main goals of the chemistry of naturally occurring compounds is screening for promising biologically active substance from plant origin. Many plants, commonly used as vegetable foods, have been employed during the past centuries, as spices, foods or for traditional medicine. The major contribution of plants to human diet is due to the large amount of vitamins, folic acid and minerals. However they contain other secondary metabolites, called nutraceuticals, that have recently been at the center of an intense scientific debate (1, 2). Edible plants are rich in phytochemicals such as terpenoids, flavonoids, alkaloids, pigments, polyphenolic, fitosterols, plyunsaturated fatty acids which may play a important role for healt benefits. Mediterranean diet includes large amounts of food plants (fruits, vegetables, nuts, seeds, wine, olive oil) (3) and the prevention of the oxidative reactions has been associated with lower risk factors for coronary heart desease (CHD) such as lower blood plasma cholesterol levels (4).
A sensitive reduction of human chronic degenerative diseases was also observed as in cancer or Alzehimer's desease, Parkinson’s desease, autoimmune pathology, multiple sclerosis. (5,6). Epidemiological studies have suggested a positive association with antioxidant compounds in foods and beverages such as polyphenols. From a chemical point of view polyphenols are classified in two groups: the flavonoids and the nonflavonoids. The flavonoid family >>>