基于MSPD-HPLC法的食用植物油中苯并[a]芘含量测定

建立了食用植物油中痕量苯并[a]芘的基质固相分散萃取-高效液相色谱（MSPD—HPLC）检测方法。以C18和Florisil硅土作分散剂,乙腈为洗脱剂,洗脱液氮吹浓缩后HPLC测定,结果表明,方法检出限为2μg／kg,加标回收率在92％-102％,相对标准偏差RSD在3．1％～3．8％。     

芘胁迫对菠菜生长、叶片叶绿素和抗氧化酶活性的影响

采用盆栽试验研究土壤中不同施芘水平对菠菜(Spinacia oleracea L.)生长、叶片叶绿素和抗氧化酶活性的影响.结果表明:50～200 mg·kg-1施芘水平下菠菜幼苗叶片的各项叶绿体色素含量、不同时期的根长与对照均无显著差异;施芘浓度大于50 mg·kg-1,菠菜苗期的株高、根和茎叶的鲜重显著降低;芘大于100 mg·kg-1时,菠菜收获期的根和茎叶干重显著受到抑制;芘胁迫导致菠菜幼苗叶片的丙二醛累积量提高,可溶性糖含量增加;同时叶片的APX、CAT、POD活性和非酶抗氧化剂AsA含量均随芘浓度增加而显著增加.     

Interaction of Thalassia testudinum Metabolites with Cytochrome P450 Enzymes and Its Effects on Benzo(a)pyrene-Induced Mutagenicity

The aim of the present work was to evaluate the effects of Thalassia testudinum hydroethanolic extract, its polyphenolic fraction and thalassiolin B on the activity of phase I metabolizing enzymes as well as their antimutagenic effects. Spectrofluorometric techniques were used to evaluate the effect of tested products on rat and human CYP1A and CYP2B activity. The antimutagenic effect of tested products was evaluated in benzo[a]pyrene (BP)-induced mutagenicity assay by an Ames test. Finally, the antimutagenic effect of Thalassia testudinum (100 mg/kg) was assessed in BP-induced mutagenesis in mice. The tested products significantly (p < 0.05) inhibit rat CYP1A1 activity, acting as mixed-type inhibitors of rat CYP1A1 (Ki = 54.16 ± 9.09 μg/mL, 5.96 ± 1.55 μg/mL and 3.05 ± 0.89 μg/mL, respectively). Inhibition of human CYP1A1 was also observed (Ki = 197.1 ± 63.40 μg/mL and 203.10 ± 17.29 μg/mL for the polyphenolic fraction and for thalassiolin B, respectively). In addition, the evaluated products significantly inhibit (p < 0.05) BP-induced mutagenicity in vitro. Furthermore, oral doses of Thalassia testudinum (100 mg/kg) significantly reduced (p < 0.05) the BP-induced micronuclei and oxidative damage, together with an increase of reduced glutathione, in mice. In summary, Thalassia testudinum metabolites exhibit antigenotoxic activity mediated, at least, by the inhibition of CYP1A1-mediated BP biotransformation, arresting the oxidative and mutagenic damage. Thus, the metabolites of T. testudinum may represent a potential source of chemopreventive compounds for the adjuvant therapy of cancer.     

高效液相色谱法测定熟肉制品中的苯并(α)芘

采用匀浆、超声波提取,改进的液一液分配净化,用高效液相色谱仪-荧光检测器检测,建立了熟肉制品中苯并（α）芘的测定方法。对样品前处理过程中的提取、净化条件进行了优化。所得线性方程为Y=8．69×10^5X-1．59×10^4（r=0．9999）。当样品中苯并（α）芘的浓度为1．0—30．0μg/kg时,加标平均回收率在84．6％～90．8％,其5次测定的日内相对标准偏差在2．88％～5．40％之间,日问相对标准偏差在1．47％～3．04％之间,检出限小于0．5μg／kg。该方法有机溶剂用量少,方法简单快速,灵敏度高,适合于熟肉制品中苯并（α）芘的测定。     

芘在土壤中的吸附和解吸行为研究

研究了芘在6种有机质和黏粒含量不同的土壤中吸附和解吸行为。结果表明,各土壤对芘的吸附速率很快,2d即可达到稳态,而芘的解吸速率却很缓慢,出现了解吸滞后现象。Freund lich方程能够很好的拟合6种土壤的吸附等温线,芘在土壤中的吸附自由能变化量为7.02~14.43 kJ.mol-1,表明芘在土壤中的吸附以物理吸附为主。芘在土壤中的吸附常数在0.059~30.966之间,当土壤有机质含量高于1%时,吸附常数与土壤有机质含量成正比,而解吸速率与有机质含量成反比,解吸进行30 d,只有9.84%~54.59%吸附的芘从土壤中解吸;有机质含量低于1%时,黏粒和有机质含量都对土壤的吸附/解吸能力有重要影响。     

一种新的抗多环芳烃多克隆抗体的制备（英文）

为实现环境中多环芳烃(PAHs)污染物的快速检测,制备了抗多环芳烃多克隆抗体,用于多环芳烃免疫学检测试剂盒的研制。采用活性酯法将半抗原芘丁酸(1-PBA)分别于牛血清白蛋白(BSA)和卵清白蛋白(OVA)进行偶联,获得PBA-BSA和PBA-OVA偶联物,以PBA-BSA偶联物免疫新西兰大白兔,获得针对多环芳烃的抗血清。以PBA-OVA偶联物为包被原,间接ELISA法检测抗血清,效价为102 400,经纯化后得到多克隆抗体。采用间接竞争ELISA法绘制了针对芘的标准曲线,得到该方法的IC50值为0.06 mg/L,检出限为0.01 mg/L。与16种多环芳烃的交叉反应实验结果表明该抗体对高环PAHs的亲和力较高。反应体系中添加低于40%的甲醇对ELISA结果无影响。该抗体的制备及特性鉴定对后续多环芳烃酶联免疫试剂盒的开发奠定了技术基础。     

气-质联用法测定干槟榔中苯并(α)芘含量

提出一种测定干槟榔中痕量苯并(α)芘的方法,试样经氢氧化钾皂化,弗洛里硅土固相柱净化,正已烷二氯甲烷液洗脱,浓缩,用标准加入法和GC-MS(气相色谱-质谱)定量测定。试验证明,测定结果平均回收率达到80%以上,相对标准偏差RSD为0.97%～1.2%,方法线性、精密、准确度均良好,可以满足分析的要求。     

nTiO2与菲、芘对日本虎斑猛水蚤联合毒性的研究

以日本虎斑猛水蚤为实验生物,研究了纳米二氧化钛（nTiO2）及与菲、芘联合的急性毒性效应.实验结果表明：当ρ（nTiO2）≤5 mg/L时对日本虎斑猛水蚤的存活率无显著性的影响,而当ρ（nTiO2）≥20 mg/L时则有显著性影响;菲、芘都可与纳米二氧化钛（1 mg/L）联合表现出比单一污染物更大的毒性效应,其中芘与纳米二氧化钛存在显著的联合协同效应.研究表明,纳米材料会与环境中其他的污染物相互作用,从而对水生生物表现出间接的毒性作用,因此在海洋环境中纳米材料的潜在危害不容忽视.     

Changes of biomarkers with oral exposure to benzo(a)pyrene, phenanthrene and pyrene in rats

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants present in air and food. Among PAHs, benzo(a)pyrene(BaP), phenanthrene (PH) and pyrene (PY) are considered to be important for their toxicity or abundance. To investigate the changes of biomarkers after PAH exposure, rats were treated with BaP (150 µg/kg) alone or with PH (4,300 µg/kg) and PY (2,700 µg/kg) (BPP group) by oral gavage once per day for 30 days. 7-ethoxyresorufin-O-deethylase activity in liver microsomal fraction was increased in only BaP groups. The highest concentration (34.5 ng/g) of BaP, was found in muscle of rats treated with BaP alone at 20 days of treatment; it was 23.6 ng/g in BPP treated rats at 30 days of treatment. The highest PH concentration was 47.1 ng/g in muscle and 118.8 ng/g in fat, and for PY it was 29.7 ng/g in muscle and 219.9 ng/g in fat, in BPP groups. In urine, 114-161 ng/ml 3-OH-PH was found, while PH was 41-69 ng/ml during treatment. 201-263 ng/ml 1-OH-PY was found, while PH was 9-17 ng/ml in urine. The level of PY, PH and their metabolites in urine was rapidly decreased after withdrawal of treatment. This study suggest that 1-OH-PY in urine is a sensitive biomarker for PAHs; it was the most highly detected marker among the three PAHs and their metabolites evaluated during the exposure period and for 14 days after withdrawal.     

Effects of amifostine on formation of abdominal aortic aneurysm in mice induced by benzo[a] pyrene

AIM: To study the role of amifostine on the formation of benzo[a]pyrene (BaP)-induced abdominal aortic aneurysm (AAA) in C57BL/6J mice and the underlying mechanism. METHODS: RAW246.7 mononuclear macrophage in vitro were divided into control group, DMSO group, BaP group, low dose (1 μmol/L) amfostine treated group, middle dose (5 μmol/L) amfostine treated group and high dose (25μmol/L) amfostine treated group. The influence of BaP on the expression of matrix metalloproteinase (MMP)-9, MMP-12, TNF-α, NF-κB in the RAW246.7 mononuclear macrophages in vitro was determined by Western blot. Male C57BL/6J mice (8 months old) were divided into control group, model group (AngII+BaP group), low dose (50 mg/kg) amfostine treated group and high dose (100 mg/kg) amfostine treated group. After 6 weeks, the abdominal aorta were isolated. The aortic tissues were subjected to HE and Masson staining. The vascular wall structure, infiltration of macrophage, the expression of MMP-9, MMP-12, TNF-α, NF-κB were evaluated by Western blot and immunochemistry staining. RESULTS: Amifostine attenuated BaP-induced expression of TNF-α, MMP-9, MMP-12, NF-κB in the RAW246.7 mononuclear macrophages (P<0.05). The results of animal experiments showed that the incidence of AAA in high dose amifostine treated group were significantly lower than that in low dose amifostine treated group and model group (P<0.05). Immunohistochemistry staining observation showed that amifostine inhibited the aortic macrophage infiltration more obviously in high amifostine treated group compared with model group and low dose amifostine treated group (P<0.05). Compared with model group and low dose amifostine treated group, the MMP-9, MMP-12, TNF-α and NF-κB expression of abdominal aorta in high amifostine treated group was reduced significantly (P<0.05). CONCLUSION: Amifostine inhibits BaP-induced activation of macrophages, and also prevents the formation of abdominal aortic aneurysm in C57BL/6J mice induced by BaP by inhibition of the NF-κB pathway, macrophage infiltration and the expression of TNF-α and MMPs.