Plantago major seed gum: Ultrasound-assisted extraction, purification and optimization

Gums are polysaccharides that mostly originated from plant and microbial sources and they are widely used in food and pharmaceutical industries as thickening, gelling, stabilizer and emulsifier. Plantago major L. is a plant that sorted in Plantaginaceae family which have been used for a long time as an antiinfective, immune-modulating, antioxidant and also wound-curing purposes. Response Surface Methodology (RSM) and Box-Behnken design was used to optimize the ultrasound-assisted extraction of Plantago major seed gum process. Optimization was done at two stages: Ultrasound stage with three variables: ultrasonic power (200 – 400W), ultrasonic temperature (25 - 40°C) and ultrasonic time (15 – 30 min) and Extraction stage with three variables: seed:water ratio (1:10 – 1:20), extraction temperature (55 - 75°C) and extraction time (20 – 40 min). The results indicated that ultrasonic power of 400W, ultrasonic temperature of 35°C and ultrasonic time of 30 min, seed:water ratio of 1:20, extraction temperature of 75°C and extraction time of 40 min were the optimum conditions for extraction process. After extraction, purification and optimization, the chemical composition of the resulted gum including moisture, ash, protein and carbohydrate were evaluated. The results demonstrated that the gum consisted of 6.20% moisture, 3.23% ash, 2.03% protein and 88.47% carbohydrate. The monosaccharide composition analysis of this gum by HPLC indicated that the main monosaccharide constituents were arabinose (56.72%) and rhamnose (21.84%).