Avicennia marina biomass characterization towards bioproducts

Avicennia marina is the only naturally occurring mangrove specie in the arid Arabian Gulf coast of the United Arab Emirates (UAE). Due to the water scarcity of this arid-region, A. marina is a precious biomass resource for the UAE that does not require fresh water for growing, and is able to grow in the Arabian Gulf high salinity conditions, over 40g/kg. This non-fresh water lignocellulosic arid-region bioresource may be used for the production of high valuable chemicals. The objective of the present manuscript is to characterize the lignocellulosic composition of Arabian Gulf A. marina, as a first attempt to highlight its importance in a biobased economy in arid regions. Avicennia marina stem, leaves and pneumatophors samples were collected from two locations in the United Arab Emirates. A. marina samples were chemically characterized for sugar composition, ash content and byproducts using standardized protocols. The analysis revealed that A. marina arabinan, xylan, glucan and lignin composition ranges, in g/100g_TS (TS: total solids), between 1-22, 5-18, 10-31, and 21-48, respectively. The highest composition of xylan and glucan (g/100g_TS) was obtained for stems and pneumatophors, 45 and 38, respectively. Xylan and glucan are the polymeric precursors for the production of high value chemicals, e.g. furfural and hydroxymethylfurfural (HMF), respectively. Under the characterization conditions, it was obtained furfural and HMF (g/100g_TS) in the ranges of 0.05-0.42, and 0.45-2.1, respectively.