Genetic Differentiation between Natural and Hatchery Stocks of Japanese Scallop (Mizuhopecten yessoensis) as Revealed by AFLP Analysis

Japanese scallop (Mizuhopecten yessoensis) is a cold-tolerant bivalve that was introduced to China for aquaculture in 1982. In this study, amplified fragment length polymorphism (AFLP) markers were used to investigate levels of genetic diversity within M. yessoensis cultured stocks and compare them with wild populations. Six pairs of primer combinations generated 368 loci among 332 individuals, in four cultured and three wild populations. High polymorphism at AFLP markers was found within both cultured and wild M. yessoensis populations. The percentage of polymorphic loci ranged from 61.04% to 72.08%, while the mean heterozygosity ranged from 0.2116 to 0.2596. Compared with wild populations, the four hatchery populations showed significant genetic changes, such as lower expected heterozygosity and percentage of polymorphic loci, and smaller frequency of private alleles, all indicative of a reduction in genetic diversity. Some genetic structures were associated with the geographical distribution of samples; with all samples from Dalian and Japan being closely related, while the population from Russia fell into a distinct clade in the phylogenetic analysis. The genetic information derived from this study indicated that intentional or accidental release of selected Japanese scallops into natural sea areas might result in disturbance of local gene pools and loss of genetic variability. We recommend monitoring the genetic variability of selected hatchery populations to enhance conservation of natural Japanese scallop resources.     

Physical measures of sensory texture in thawed sea scallop meat

An instrumental method of texture measurement for scallop (Placopecten magellanicus) meats after frozen storage has been developed to replace the sensory method. Non-destructive and destructive compressive forces at 50 and 80% deformation respectively and shear peak force gave significant correlation coefficients of 0.89, 0.78 and 0.82 respectively with sensory evaluation of the cooked meats. The coefficient of variation associated with the compression method was smaller, however, than with the shear method.     

扇形中深孔爆破块度预测的神经网络法

针对现有爆破块度预测模型存在的不足,应用神经网络理论,研究了具体矿岩条件下的扇形中深孔爆破块度预测的神经网络方法.构建了三层前馈型神经网络结构,并根据扇形中深孔爆破实例,采用BP 算法对网络进行了训练,建立了具体矿岩条件下的扇形中深孔爆破块度分布与其影响因素间的非线性映射关系.采用测试样本对模型进行了测试,结果表明,所建立的模型用于扇形中深孔爆破块度的预测是可行的,模型精度是可靠的.     

栉孔扇贝内脏、裙边油中脂肪酸组成分析

采用索氏提取法对栉孔扇贝内脏和裙边中的油脂进行提取,用气相色谱对其油的脂肪酸组成进行分析测定.结果表明:扇贝内脏油脂含量远远高于扇贝裙边,扇贝内脏油脂含量占70℃烘干样品的14％以上;扇贝内脏和裙边油中不饱和脂肪酸分别为68.10％和55.29％,尤其是(EPA+DHA)含量高,内脏油为44.12％,裙边油为39.77％;扇贝内脏油中(EPA+DHA)含量高于目前报道的各种鱼油的( EPA+ DHA)含量(12％～42％).从扇贝内脏中提取油脂将有较大的市场潜力.     

贮存过程中即食贝柱风味成分分析

采用定量描述分析法及其顶空固相微萃取(HS-SPME)与气相色谱-质谱联用(GC-MS)法分析即食贝柱贮存初期和末期的风味成分及相对含量。结果:定量描述分析法评价即食贝柱得到9种气味描述词:甜味、煮玉米味、海风味、酸味、刺鼻味、干鱼味、煮鸡蛋味、Kamaboko、即食贝柱味;从贮存初期和末期的即食贝柱中分别鉴定出44和55种主要风味成分;即食贝柱的风味成分主要为硫醚类、烷烃类、酮类、醇类、呋喃类、吡嗪类及其他类;二甲硫醚是即食贝柱的主要风味化合物;真空包装的即食贝柱在37℃±1℃贮存3个月时已经变质,Maillard反应是引起即食贝柱变质的主要原因,3-甲基-吡嗪、2,4,6-三甲基癸烷是贮存期间即食扇贝褐变后产生不良风味的主要组分。     

扇贝裙边酱发酵工艺及营养成分分析的研究

为了降低扇贝酱产品成本,增加贝类产品的附加值,以扇贝裙边为主要原料,经米曲霉和豆粕制曲,扇贝裙边与豆曲的质量比为4∶1,加入中性蛋白酶2000U/g,添加12%食盐,在40℃恒温培养箱中发酵8d后以1%接种量接种耐盐四联球菌,在30℃恒温培养箱中发酵7d,25℃恒温培养箱中后熟30d,磨细后真空包装、灭菌制成扇贝裙边酱。对其营养成分、理化指标及游离氨基酸分析结果表明：蛋白质含量为20.04g/100g,脂肪含量为0.82g/100g,氨基酸态氮为1.76g/100g,19种游离氨基酸总量为9.82g/100g,游离的必需氨基酸总量为4.16g/100g。以上5个指标除脂肪含量外均显著高于由贝柱和豆粕、贝柱和面粉发酵生产的扇贝豆酱和扇贝面酱。该研究为降低扇贝酱产品成本提供了实验依据。     

鑫达黄金矿业急倾斜薄矿体中深孔采矿方法的研究与优化

近年来，随着开采技术的发展，急倾斜薄矿脉采用中深孔采矿越来越多。为了降低生产成本，提高经济效益和安全系数。通过在矿房对扇形中深孔和平行中深孔进行现场试验，得到扇形中深孔比平行中深孔工程量少、千吨采切比小的结论。将扇形中深孔采矿方法在急倾斜薄矿脉中进行推广应用，取得了一定经济效益。     

海鲜酱油的研究与开发现状

介绍新型调味品的发展现状,开发与研究海鲜酱油的意义及市场前景,国内外以低值鱼、扇贝裙边为主要原料,经过科学的加工酿造的各种营养丰富、海鲜风味浓郁的海鲜酱油。     

海湾扇贝多肽混合物对人肝癌HepG2细胞增殖和凋亡的影响

采用CCK-8（Cell Counting Kit-8）法检测海湾扇贝多肽混合物对体外培养的人肝癌HepG2细胞增殖的抑制作用,利用倒置显微镜及流式细胞仪观察、分析其对HepG2细胞的形态和细胞凋亡的影响。结果表明：不同质量浓度海湾扇贝多肽混合物（4、6、8、10、12 mg/mL）能够抑制人肝癌HepG2细胞的生长,且抑制率随海湾扇贝多肽混合物质量浓度的增加而升高。经12 mg/mL海湾扇贝多肽混合物处理后,HepG2细胞的形态发生了明显改变,表现为细胞皱缩、透明度降低、细胞核固缩等,并出现了凋亡小体。海湾扇贝多肽混合物可诱导HepG2细胞凋亡。