黄芩抗内毒素活性物质的分离提取与活性研究

目的 从黄芩中提取具有拮抗内毒素(LPS)活性的物质.方法 采用大孔吸附树脂和高效液相色谱(HPLC)等技术将黄芩水提物分离成若干组分,应用生物传感器技术检测各组分与LPS的活性中心Lipid A的结合活性,动态比浊法鲎试验检测各组分(2.0 mg/L)对LPS(02 μg/L)的中和作用,籍此筛选出活性组分;逆转录聚合酶链式反应(RT-PCR)检测所筛组分对LPS诱导的RAW264.7细胞的Toll样受体4(TLR4)mRNA表达的影响,ELISA法检测所筛组分对LPS(100 μg/L)刺激的RAW264.7细胞释放肿瘤坏死因子的影响.结果 获得5种HPLC产物S3K1～5,其中S3K1与Lipid A结合活性最高,S3K1(2.0 mg/L)可显著抑制LPS(0.2 μg/L)介导的鲎试剂的凝结反应(P<0.05);以LPS(100 μg/L)刺激RAW264.7细胞,其TLR4 mRNA表达增强,给予40、80、160 mg/L的S3K1预处理后能减弱LPS诱导RAW264.7细胞的TLR4 mRNA表达(P<0.05);单纯LPS刺激RAW264.7细胞释放的TNF-α为(1 757.61±207.25)ng/L(对照组),给予40、80、160 mg/L的S3K1预处理后TNF-α浓度依次为(1324.53±149.73)、(893.87±140.77)、(799.97±124.21) ng/L,随S3K1剂量递增而减低,均显著低于对照组(P<0.05).结论 从黄芩中提取到具有拮抗LPS活性的组分S3K1,S3K1在体外对LPS具有一定的中和作用,可抑制LPS诱导的RAW264.7细胞的,TLR4 mRNA表达,进而抑制LPS诱导的RAW264.7细胞活化.

Extraction and biologic activities of active anti-lipopolysaccharide compound from Scutellaria baicalensis Georgi

Objective To isolate and extract the anti-lipopolysaccharide (LPS) active compounds from Scutellaria baicalensis Georgi. Methods A series of fractions was prepared by macroporous adsorptive resins and HPLC from the aqueous extract of the herb. Their binding activity to lipid A and the neutralization to LPS were detected by the biosensor technology and kinetic turbidimetric limulus test. The active compounds against LPS were screened. RT-PCR and ELISA was used respectively to detect the expression of TLR4 mR...