摘要
采用量子化学MOPAC -AM 1法计算了 2 3种有机物的生成热ΔHf、分子最高占有轨道能EHOMO、分子最低空轨道能ELUMO、分子总表面积STSA及偶极矩 μ .结合辛醇 -水分配系数logKOW对生物降解速率常数lnK进行了定量结构 -生物降解性关系 (QSBR)分析 .对 1 1种取代苯和 1 2种脂肪族化合物分别做出如下多元回归方程 :-lnK =1 .82 + 0 .0 1 53STSA+ 1 2 4× 1 0 - 3ΔHf+ 0 .0 981 μ ,n =1 1 ,R2 =0 .73 9,s=0 .1 45,F =6.62 ,p =0 .0 1 9;-lnK =3 .0 6+ 0 .0 2 64STSA+ 3 0 8× 1 0 - 3ΔHf-0 .1 1 9μ ,n =1 2 ,R2 =0 .867,s=0 .2 1 2 ,F =1 7.3 8,p =0 .0 0 1 .应用所得QSBR模式预测了 2 3种有机物的生物降解性 ,方程对大多数化合物拟和很好 .结果表明 ,所研究有机物的生物降解性主要与分子大小、稳定性及分子极性有关 ,化合物与酶的活性点结合或反应是影响微生物降解的主要因素 .
The heat of formation (Δ H f ), energy of the highest occupied molecular orbital ( E HOMO ), energy of the lowest unoccupied molecular orbital ( E LUMO ), total surface area ( S TSA ), and dipole moment( μ ) of 23 organic chemicals were calculated by quantum chemical method MOPAC 6.0-AM 1. The quantitative structure-biodegradability relationship studies were performed with biodegradation kinetic constant ln K . Through multiple regression, 2 equations were obtained as follows: -ln K =1.82+0.0153 S TSA +1 24×10 -3 Δ H f +0.0981 μ, n=11,R 2=0.739,s=0.145,F=6.62,p=0.019; -ln K =3.06+0.0264 S TSA +3 08×10 -3 Δ H f -0.119 μ, n=12,R 2=0.867,s=0.212,F=17.38,p=0.001. The QSBR equations were used to calculate biodegradability and most compounds fit well. It has shown that the biodegradability of studied compounds is related mainly to the size, stability and polartiy of molecular. The rate-limiting step within the overall biodegradation process is the rates of binding with the active site of an enzyme and enzymatic reaction instead of the rates of uptake and transport.
出处
《东北师大学报（自然科学版）》
CAS
CSCD
北大核心
2001年第2期60-64,共5页
Journal of Northeast Normal University(Natural Science Edition)
基金
国家自然科学基金资助项目 ( 2 98770 0 4 )
