Extraction and characterization of volatile compounds and fatty acids from red and green macroalgae from the Romanian Black Sea in order to obtain valuable bioadditives and biopreservatives

Three species of macroalgae, Ceramium virgatum (Rhodophyta), Ulva intestinalis, and Cladophora vagabunda (Chlorophyta), harvested from the Romanian Black Sea coast, were studied as sources of valuable compounds that could be used as additives and biopreservatives. Volatile compounds including hexanal (11.2 %), octane (9.8 %), nonanal (7.0 %), octanal (6.7 %), 2,5,5-trimethyl-2-hexene (4.7 %), 3-hexen-2-one (4 %), and o-cymene (3.6 %) were identified as the major components in the biomass extract of C. vagabunda. In C. virgatum, the major volatile components were 3-hexen-2-one (27.9 %), acetone (12.4 %), hexanal (3.4 %), and o-cymene (2.7 %). The major volatile compounds of U. intestinalis were hexanal (14.6 %), trichloromethane (7.3 %), nonanal (5.6 %), 3-hexen-2-one (5.3 %), and octanal (3.1 %). Some of these compounds have industrial applications as additives in the food, pharmaceutical, or cosmetics industries. The U. intestinalis extract had a greater content of mono- and polyunsaturated fatty acids around 46.0 % as compared with 42.0 % for C. vagabunda and 31.9 % for C. virgatum. The most abundant fatty acids were palmitic acid (C16:0), arachidonic acid (C20:4n-6), and oleic acid (C18:1ω-9cis). The antimicrobial effect of fatty acid extracts was tested against four pathogenic bacteria. The minimum inhibitory concentrations of C. vagabunda, C. virgatum, and U. intestinalis fatty acids extracts were 1.8, 3.8, and 3.8 mg mL^?1, respectively, for all bacterial strains. This study can help the efforts of finding new, value-added uses for natural marine resources.