VALORISATION OF WILD EDIBLE AND MEDICINAL PLANTS THROUGH PHYTOCHEMICAL ANALYSES AND EVALUATION OF THEIR POTENTIAL BIOLOGICAL PROPERTIES

THE AIM OF THIS PHD PROJECT WAS THE VALORISATION OF WILD FOOD AND MEDICINAL PLANTS SELECTED BY ETHNOBOTANICAL RESEARCH AND ECOLOGICAL DATA THROUGH PHYTOCHEMICAL INVESTIGATIONS AND STUDIES OF THEIR POTENTIAL BIOLOGICAL PROPERTIES. DURING THE FIRST YEAR, WE FOCUSED THE ATTENTION ON THE FLOWERS EXTRACT OF CRATAEGUS LACINIATA UCRIA (ROSACEAE), WILD-GROWING IN WESTERN SICILY. LC-MS ANALYSES SHOWED 41 COMPOUNDS IN THE FLOWER EXTRACT (CLF), MAINLY C- AND O-FLAVONOID DERIVATIVES. THE FLOWER EXTRACT INDICATED STRONG ANTIOXIDANT POTENTIAL IN DPPH, ABTS, AND FRAP ASSAYS. IN ADDITION, CLF EXHIBITED ANTI-MELANOGENIC EFFECTS IN DANIO RERIO (ZEBRAFISH) AND SIGNIFICANT INHIBITORY ACTIVITY AGAINST TYROSINASE, Α-AMYLASE, AND Α-GLUCOSIDASE ENZYMES. THESE RESULTS REVEALED C. LACINIATA AS A VALUABLE SOURCE OF BIOACTIVE COMPOUNDS WITH POTENTIAL PHARMACEUTICAL AND COSMECEUTICAL APPLICATIONS. THE FINDINGS IMPLY THAT CLF CAN BE A PROMISING SOURCE OF BIOACTIVE COMPOUNDS FOR APPLICATION IN PHARMACEUTICAL AND COSMECEUTICAL INDUSTRIES. THEN, THE SECOND YEAR, FRUIT EXTRACTS OF DIFFERENT CRATAEGUS SPECIES WERE STUDIED. THE LC-MS ANALYSIS OF CRATAEGUS FRUIT EXTRACTS EXHIBITED 25 MAJOR COMPONENTS, MAINLY FLAVONOIDS, PHENOLIC ACIDS, AND FATTY ACIDS. QUANTITATIVE ANALYSIS USING UHPLC-MS SHOWED SPECIES-SPECIFIC DIFFERENCES: C. LAEVIGATA AND C. ZICHICHIANUS WERE RICH IN HYPEROSIDE, C. AZAROLUS CONTAINED THE HIGHEST LEVELS OF CYANIDIN-O-GLUCOSIDE, WHILE C. AZAROLUS SUB. ARONICA SHOWED THE HIGHEST VITEXIN CONTENT. THE EXTRACTS EXHIBITED STRONG ANTIOXIDANT ACTIVITY IN DPPH, ABTS, AND FRAP ASSAYS, AND DEMONSTRATED POTENT INHIBITION OF Α-GLUCOSIDASE, SUGGESTING POTENTIAL ANTIDIABETIC PROPERTIES. MOREOVER, DURING THE SAME YEAR THE PHYTOCHEMICAL INVESTIGATION OF STEM BARK EXTRACTS OF CEDRELA ODORATA (MELIACEAE) AIMED AT IDENTIFYING NEW LIGNAN AND NEOLIGNAN DERIVATIVES WITH POTENTIAL ANTIANGIOGENIC PROPERTIES, WAS CARRIED OUT. FROM THE, TWO PREVIOUSLY UNDESCRIBED 8’,9’-BIS-NOR-NEOLIGNANS—9-ACETYLTOONIN C AND THREO-GUAIACYLGLYCEROL-Β-METHYL VANILLATE ETHER—WERE ISOLATED AND STRUCTURALLY ELUCIDATED BY 1D/2D NMR AND HRESIMS ANALYSES. TOGETHER WITH RELATED LIGNANS FROM OUR CHEMICAL LIBRARY, THESE COMPOUNDS WERE EVALUATED FOR ANTIANGIOGENIC ACTIVITY USING THE DANIO RERIO (ZEBRAFISH) EMBRYO MODEL. COMPOUNDS 1–3 SHOWED THE ST RONGEST INHIBITION OF BLOOD VESSEL FORMATION, WITH COMPOUND 2 DISPLAYING AN EFFECT COMPARABLE TO THE REFERENCE COMPOUND 2-METHOXYESTRADIOL. THESE FINDINGS CONTRIBUTE TO THE UNDERSTANDING OF NEOLIGNANS AS PROMISING SCAFFOLDS FOR THE DEVELOPMENT OF NATURAL ANTIANGIOGENIC AGENTS. IN ADDITION, THE PHYTOCHEMICAL STUDY OF EXUDATE AND ARIAL PARTS EXTRACTS OF LAVANDULA PUBESCENS, A SPECIES TRADITIONALLY USED IN SAUDI ARABIA FOR ITS ANTIBACTERIAL AND ANTI-INFLAMMATORY PROPERTIES, LED TO THE ISOLATION OF SEVEN NEW DITERPENOIDS ALONG WITH FOUR KNOWN PIMARANES AND THREE KNOWN FLAVONOIDS FROM ITS EXUDATES AND THE SURFACE EXTRACT, FRACTIONS AND PURE COMPOUNDS OF L. PUBESCENS WERE STUDIED FOR THEIR ANTI-INFLAMMATORY ACTIVITY AGAINST THP-1 CELLS. BASED ON THE STUDY CARRIED OUT IN THE SECOND YEAR ON THE L. PUBESCENS, DURING THE THIRD YEAR A CHEMICAL THE INVESTIGATION OF ARIAL PART EXTRACT OF L. PUBESCENS WAS PERFORMED AND LED TO THE ISOLATION OF DITERPENOIDS, INCLUDING NINE NEW DITERPENS (1-9) AND SIX KNOWN MONOTERPENES (15-20), TOGETHER WITH THE KNOWN ENT-PIMAR-8(14)-15,16DIOL (HANG ET AL 2005), 15(S)-ISOPIMAR-7-EN-15,16 DIOL. THEIR STRUCTURES WERE DETERMINED BY 1D AND 2D NMR SPECTROSCOPY, HRESIMS ANALYSES. FURTHERMORE, ANTIMICROBIAL ACTIVITY OF THE EXTRACTS AND SUBSEQUENTLY FRACTIONS, AND MOLECULES WAS EVALUATED.