| 摘要 |
Heteropolysaccharide S-657, which is obtainable by fermentaion of a culture of Xanthomonas campestris, ATCC 53159, which contains no mannose or pyruvate in its structure, and which comprises principally carbonhydrate, about 12% protein and about 7% (calculated as 0- accetyl) acyl groups, the carbohydrate portion containing about 19% glucuronic acid, and the neutral sugars rhamnose and glucose in the approximate molar ratio of 2:1. S-657 has thickening, suspending and stabilising properties and its aq. solns. of 0.01-1 wt.% content are particularly useful as oil-well treating fluids. |
