Application of subcritical water method in extraction from frankincense gum and evaluation of antioxidant and antibacterial ability of extracts.

Extraction by the subcritical water method was studied as an efficient, economical, green, and environmentally friendly method to extract effective compounds of frankincense gum. For this purpose, subcritical water was used at temperatures of 120 and 160 ° C for 5 and 15 minutes. The amount of total phenolic compounds, radical scavenging ability, and antimicrobial properties of the extracts were investigated. The encapsulated powder of the extract obtained from the optimal conditions was also prepared by spray drying method and the particle size distribution and anti-aspergillus properties of that were also investigated. The results showed that the subcritical water extraction method significantly increased the extraction efficiency of frankincense gum extract. The amount of phenolic compounds extracted at 160 °C and time of 15 minutes was the highest among the extracts with 130.83 mg of gallic acid per 100g dry matter. The radical scavenging ability of the extracts from the subcritical water method was similar to that of the natural antioxidant ascorbic acid, and the extract from the maceration method as a traditional was less efficient at absorbing DPPH free radicals. Microbial results showed that the effects of extracts from maceration and subcritical water methods on Staphylococcus aureus were more than Escherichia coli. Encapsulated frankincense powder had no anti-aspergillus potency at concentrations less than 600,000 μg / ml.