根霉Rhizopus sp.TC1产酶条件的研究

根据要因实验原则,选择影响因子较大的因素进行实验,初步研究了根霉Rhizopussp.TC1的产酶条件.经实验确定优化产酶条件为:稻草∶麸皮=1∶1;固液比=1∶3;接种量9 mL种子液/100 g湿基;温度28℃,在此条件下发酵96 h,FPA和CMC酶活分别达到17.8 IU/g、187.0 IU/g,较优化前的12.3 IU/g、131.6 IU/g分别提高了45%和42%.     

2,3-Dihydroxybiphenyl dioxygenase gene was first discovered in Arthrobacter sp. strain PJ3

Bacterium strain PJ3,isolated from wastewater and identified as Arthrobacter sp. bacterium based on its 16S rDNA gene,could use carbazole as the sole carbon,nitrogen and energy source. The genomic library of strain PJ3 was constructed and a positive clone JM109(pUCW402) was screened out for the expression of dioxygenase by the ability to form yellow ring-fission product. A 2,3-dihydroxybiphenyl dioxygenase(23DHBD) gene of 933 bp was found in the 3360 bp exogenous fragment of pUCW402 by GenSCAN software and BLAST analysis. The phylogenetic analysis showed that 23DHBD from strain PJ3 formed a deep branch separate from a cluster containing most known 23DHBD in GenBank. Southern hybridization confirmed for the first time that the 23DHBD gene was from the genomic DNA of Arthrobacter sp. PJ3. In order to test the gene function,recombinant bacterium BL21(pETW-8) was constructed to express 23DHBD. The expression level in BL21(pETW-8) was highest compared with the recombinant bacteria JM109(pUCW402) and strain PJ3. We observed that 23DHBD was not absolute specific. The enzyme activity was higher with 2,3-dihydroxybiphenyl as a substrate than with catechol. The substrate specificity assay suggested that 23DHBD was essential for cleavage of bi-cyclic aromatic compounds during the course of aromatic compound biodegradation in Arthrobacter sp. strain PJ3.     

松树两种病原菌拮抗微生物的筛选

采用组织分离法从健康的和感染松枯梢病的松树针叶上分离了叶栖微生物1 862株.选取有代表性的菌株通过室内平皿对峙培养,初步筛选出对松枯梢病菌和松赤枯病菌具有较好生防潜力的菌株12株.其中,拮抗细菌菌株6株、酵母菌3株、丝状真菌木霉(Trichoderma sp.)3株,拮抗效果由强到弱依次为细菌、木霉、酵母菌,细菌无菌滤液的拮抗效果明显好于菌体本身.拮抗菌的筛选以相对抑菌效果为准,同时应考虑被抑制率和菌种本身具有的致病性.     

低温解烃菌T7-2分类鉴定及治理海洋石油污染的条件优化

从渤海油船泄漏区域的海底泥中筛选到一株能降解柴油的低温解烃菌T7-2,初步鉴定为红平红球菌(Rhodococcus erythropolis).该菌在接种到以柴油为碳源的海水中,通过补加少量氮、磷盐及微量酵母粉,15℃振荡培养7 d,降解率达到60.14%.采用响应面法(RSM)对补加营养进行了优化.方差分析表明二阶多项式模型是适合的,回归分析得到了相应的参数.T检验证明(NH4)2SO4、Na2HPO4.和酵母粉均是影响柴油降解的显著性因素.优化的补加营养条件为(NH4)2SO4为2.53 g/L、Na2HPO4为2.75 g/L和酵母粉为10.19 mg/L,验证实验和预期一致,优化后降解率达到75.09%,比优化前提高了25%.     

A new species of Munromyia Bezzi (Diptera: Tephritidae) reared from Chionanthus battiscombei (Oleaceae) in northern Kenya

Munromyia marsabitensis sp. nov. is described from the isolated mountains of Marsabit in northern Kenya. It can be distinguished from the two known congeners by the thoracic and abdominal colour patterns, structure of the male and female terminalia, and host plants. Larvae are seed predators, developing within the green, aborted fruits of Chionanthus battiscombei. Over 70% of sampled fruits (n?=?74) were infested with larvae, but nearly all of the individually infested fruits (96.1%) produced only one adult tephritid. Bactrocera biguttula, but not M. marsabitensis, was reared from ripe fruits of the same plant.     

Structure assignments of two new C-18-oxygenated steroidal ketals isolated from a pacific soft coral of the genusSinularia

Summary Two new C-18-oxygenated sterols possessing a spiroketal function (1 and2) have been isolated from a soft coral of the genusSinularia. The proposed structures are based on spectral data.     

A new species of the genus Liopeltis Fitzinger, 1843 from Vietnam (Squamata: Colubridae)

ABSTRACT

A new species of Liopeltis from central Vietnam is described based on morphological and molecular differences. Liopeltis pallidonuchalis sp. nov. is distinguished from its congeners by a combination of the following characters: one single (or missing) loreal; one single nasal shield; dorsal scales in 15–15-15 rows, all smooth; 1 preocular, 2 postoculars and 1 + 2 temporals; 7 supralabials, of which 3^rd and 4^th in contact with the eye; 8 infralabials; nasal contacting internasal; prefrontal touching or separated from supralabials; ventral scales 126–138; subcaudal scales 67–73, paired; relative tail length about 0.274–0.301; an uniform bronze body colouration; a thin postocular stripe extending from eye to end of the neck becoming indistinct posteriorly. The new species differs from the morphologically closest species Liopeltis frenata by the lower number of ventrals and subcaudals, by characteristic colouration and significant divergence in cytochrome b mtDNA gene sequences (p = 15.3–15.6%). The new species is currently known from northen and central parts of the Annamite (Truong Son) Mountains, central Vietnam, and was recorded from montane evergreen tropical forests of Kon Tum–Gia Lai Plateau (Gia Lai and Thua Thien–Hue provinces, Da Nang City) at elevations of 950–1010 m asl to karst tropical forests in Quang Binh Province in the north at elevation 150 asl. We suggest the new species should be considered as Vulnerable (VU) following the IUCN’s Red List categories. An updated taxonomic key to the Liopeltis species is provided.     

A new shield-bug species Piezodorus grossi (Het.: Pentatomidae) from the Australasian region previously confused with P. hybneri (Gmelin)

Material previously identified as Piezodorus hybneri (Gmelin) from the Australasian region is here described as a new species, P. grossi sp. nov. The two species can be distinguished on the basis of the aedeagus in the male and spermathecal proximal duct in the female.     

南靖亚热带雨林美刺亮大蚊栖息

在南靖和溪亚热带雨林中分布有数种大蚊,美刺亮大蚊(Limonia (Euglochina) sp.)是雨林中唯一观察到在圆蛛科蜘蛛网上栖息的大蚊.因此我们对美刺亮大蚊和圆蛛科蜘蛛在蜘蛛网上的同现行为进行了观察研究.借助扫描电镜技术,在比较了其他大蚊、蜘蛛等节肢动物前跗节超微结构的基础上,对美刺亮大蚊栖息于蜘蛛网行为学的形态学机制进行了初步解析.文中也对美刺亮大蚊的聚集行为与雨林温湿度的关系进行了记录.     

苯酚处理海洋微藻生物学效应的研究

主要探讨了在培养液中添加不同质量浓度(0、10、20、30、40、50、60 mg/L)的苯酚后,培养单细胞微藻(塔胞藻)产生的生物学效应.结果发现,苯酚对细胞繁殖有明显的抑制作用,特别是当苯酚质量浓度达到40 mg/L以上时,在前2轮培养的微藻的繁殖能力与对照相比均表现显著差异,个别处理甚至出现极显著差异.另外,苯酚处理后还降低藻细胞内的多种内含物(如蛋白质、叶绿素、多糖等)含量.但是,当连续培养多代后,藻细胞对不良环境就产生了一定的适应能力.