title: Isolation, structure, and surfactant properties of polysaccharides from Ulva lactuca L. from South China Sea.
abstract: Two polysaccharides (ULP1 and ULP2) were isolated through ultrasonic-assisted extraction from green seaweed Ulva lactuca L. which was collected from the South China Sea. The highest yield of 17.57% was obtained under the conditions of 2% NaOH, 90 °C, material/water mass ratio 1:80, liquid extraction 5h and subsequent ultrasound-assisted extraction 1h. The structure of ULPs were characterized with periodate oxidation followed by Smith degradation, (1)H NMR, (13)C NMR spectroscopy, FTIR, and GPC. The molecular weights of ULP1 and ULP2 were 189 kDa and 230 kDa, respectively. The structural characteristics of ULP1 and ULP2 were quite similar. They were composed of rhamnose, xylose, glucose, and glucuronic acid. The content of rhamnose, xylose, glucose, glucuronic acid, sulfate was 51.2%, 12.3%, 20.1%, 16.4%, 12.0% for ULP1, respectively, and 60.8%, 14.2%, 8.2%, 16.8%, 26.8%, respectively, for ULP2. Both ULP1 and ULP2 showed good surface activity. 5 mg/mL ULP1 (2.62×10(-2) mmol/L) decreased the water surface tension to 51.63 mN/m. The critical micellar concentration of ULP1 and ULP2 was 1.01 mg/mL (5.3×10(-3) mmol/L) and 1.14 mg/mL (5.0×10(-3) mmol/L), respectively.
authors.affiliation: Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan 570228, PR China; Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Haikou, Hainan 570228, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Tian
authors.affiliation: Key Laboratory of Tropical Biological Resources of Ministry of Education, Hainan University, Haikou, Hainan 570228, PR China; Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Haikou, Hainan 570228, PR China. Electronic address: yxq88@hotmail.com.
authors.forename: Xueqiong
authors.initials: X
authors.lastname: Yin
authors.affiliation: Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Haikou, Hainan 570228, PR China.
authors.forename: Qinghuan
authors.initials: Q
authors.lastname: Zeng
authors.affiliation: Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Haikou, Hainan 570228, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Hainan Provincial Fine Chemical Engineering Research Center, Hainan University, Haikou, Hainan 570228, PR China.
authors.forename: Junhua
authors.initials: J
authors.lastname: Chen
mesh_terms: D002240:Carbohydrate Sequence; D002681:China; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D009792:Oceans and Seas; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D017550:Spectroscopy, Fourier Transform Infrared; D044445:Ulva / Q000737:chemistry*
chemical_list: D011134:Polysaccharides
keywords: Structure; Surface property; Ulva lactuca L. polysaccharide