Biological activities of Indonesian mangroves obtained by subcritical water extraction

Abstract

Mangroves are still considered as underexploited marine resources in Indonesia, and functional materials from Indonesian mangroves are not characterized yet. In this study, different part of mangroves (Sonneratia alba leaves - SAL, Sonneratia alba roots - SAR, Sonneratia alba fruit - SAF, Rhizhopora mucronata - RMF, Rhizhopora lamarckii - RLF) were hydrolyzed using the subcritical water extraction (SCWE) system at 120 ºC. Mangroves hydrolysates (SAL, SAR, SAF, RMF and RLF) were further analyzed for total protein, sugar, reducing sugar, saponin and flavonoid content. The antioxidant capacity and functional material contents including total sugar, reducing sugar, protein, flavonoid and saponin contents. The highest flavonoid and saponin contents were obtained from RLF with the value of 20.13±0.17 mg/g and 31.83±0.18 mg/g, respectively. The antioxidant capacity and antibacterial properties of mangroves hydrolysates varied significantly based on the sample materials, with RLF showing the highest total antioxidant activity and antibacterial activity. The results of our study suggest that tropical mangroves especially R. lamarckii could be valorized efficiently, as a source of bioactive material using subcritical water extraction