Sustainable use and practical application in the industrial sector of permanent crops biomass: Orange tree (C. sinensis L.), Apricot tree (P. armeniaca L.) and Olive tree (O. europea L.).

Of the Earth's surface the 30% is occupied by forest and almost 50% is occupied by agricultural crops. Both the forest and agricultural besides producing food, feed, fiber, and a wide range of necessary products like shelter, packaging, clothing, and communications, produce a huge quantity of biomass about 956 Mt of dry matter for agriculture and the forest 18,600 Mt dry weight. Much of forest biomass is used to produce energy and heat while most of the agriculture biomass remains in the field or is burned. The recent EU Directives have encouraged state members to follow circular economy guidelines on waste reuse, especially for waste originating from wood agro-forest biomass. The biorefinery that used the lignocellulosic material has increased the production of biobased material, due to the composition of the biomass. Within the biomass are present lignin, polysaccharides, and extractives. The extractives have a huge potential in the industrial sectors. Orange trees, apricot trees, and olive trees are typical Mediterranean crops and a major feature of the heritage in the Mediterranean basin, where they play an important environmental and economic role. Given the potential of biomass in the different industrial sectors, the research was focused on the valorization of biomass of orange trees, apricot trees, and olive trees. The biomass coming of these trees was selected and bark was separated from the wood. After that different extraction techniques were applied, including maceration, ultrasound-assisted extraction, accelerated solvent extraction, and autoclaving. The extractives obtained were evaluated of the antioxidant capacity with the measurement of total polyphenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), β-Carotene bleaching assay (BCB). Integrating the antioxidant capacity values generated from the different in vitro methods above mentioned was determined the relative antioxidant capacity index (RACI). Results demonstrated the potential antioxidant activity of the bark and wood, not investigated before. Then it is moved on to analyze the molecular compound present in these extract through the LC-MS analyses and GC-MS analyses. The chemical characterization showed the presence of different natural compounds, including polyphenols, alkaloids, and flavonoids. These analyses were necessary to build an industrial product. The extract with the best antioxidant activity and the antioxidant compound was the apricot bark extract through the maceration. Studying the market of cosmetic products it was chosen to make a prototype of face cream. It was necessary to make a cytotoxicity assay both for the extract and for the cream plus the extract. These preliminary assays have demonstrated the possibility of using the extracts from orchards and olive grove in the industrial fields. Therefore, the development of innovative applications that use biomass derivatives could lead to their possible use in the market as a commodity for the chemical or cosmetic industries, giving new added value to the current use of biomass from agricultural practice. Through multi-criteria analysis, it was possible to recognize the sustainability of these cropping models and their ecological function, turning into the preservation of environmental resources, environmental quality, and quality of life.