无机磷分解菌BL-11的鉴定及其解磷能力研究

研究了解磷菌株BL-11的菌体形态、生理生化特性,结合该菌的16SrDNA序列分析结果,将菌株BL-11鉴定为侧孢短芽孢杆菌。菌株BL-11在以Ca3(PO4)2为唯一磷源的培养液中的可溶性磷得率为10.91%;在以砂子为唯一磷源的培养液中,可溶性磷得率为1.56%。分解Ca3(PO4)2的最佳条件为30℃,180r/min,pH7-8;最佳培养基配方为蔗糖20g/L,(NH4)2HCO30.3g/L,MgSO4.7H2O0.5g/L,NaCl0.3g/L,KCl0.5g/L,FeSO40.03g/L,MnSO4.H2O0.03g/L。     

几种营养物质对烟草细胞生长和CoQ_(10)含量的影响

研究了蔗糖、KH2PO4、NH 4/NO3比对烟草细胞生长和CoQ10含量的影响,结果表明,当蔗糖浓度为30g/L时,CoQ10总量最高,此时细胞产量、CoQ10含量和总量分别为198g/L、4147μg/g(dwt)、8212μg/L。在上述蔗糖浓度下,当KH2PO4起始浓度为340mg/L、NH 4/NO-3为12时,细胞产量、CoQ10含量和总量分别最高,高于此比例时有利于CoQ10形成,但不利于细胞生长。     

响应面法优化解淀粉芽孢杆菌C101发酵培养基

采用响应面法对解淀粉芽孢杆菌C101菌株产芽孢发酵培养基进行了优化。利用Plackett-Burman试验设计筛选出影响产孢的3个主要因素:MnSO4、KH2PO4和(NH4)2SO4。在此基础上运用最陡爬坡路径法逼近最大响应值区域,最后利用响应面分析法确定主要因子之间的交互作用及最佳条件。结果表明,蔗糖20 g/L,尿素4.0 g/L,豆粕4.0 g/L,KNO3 2.0 g/L,Na2HPO4 2.4 g/L,KH2PO4 0.52 g/L,(NH4)2SO4 0.55 g/L,NaCl 1.0 g/L,MgSO4·7H2O 0.50 g/L,FeSO4 0.005 0 g/L,MnSO4 0.005 4 g/L,C101最大理论芽孢含量为14.67×108个/mL。经3次平行试验验证,实际平均芽孢含量与预测芽孢含量相近,比之前的芽孢含量提高了188%。     

均匀设计法优化烟管菌产漆酶培养基

应用均匀设计、二次多项式逐步回归分析对烟管菌(Bjerkandera adusta)WZFF.W-Y11产漆酶液态发酵培养基进行优化。结果表明,培养基组成为麸皮水解液1%、淀粉24.0g/L、葡萄糖24.0g/L、豆饼粉4.8g/L、NH4Cl3.2g/L、KH2PO43.2g/L、MgSO4.7H2O0.2g/L、CuSO4.5H2O0.006g/L,起始pH6.5,在28℃、150r/min、250mL的摇瓶培养条件下可以稳定地获得9672U/L的漆酶活力。     

β-葡萄糖苷酶新型高产菌株筛选及其液态发酵培养基的优化

从腐败的玉米秸秆上分离得到一株能够发酵生产β-葡萄糖苷酶的弯颈霉属的柱孢弯颈霉菌株syzx4, 使用统计学方法对其发酵培养基进行优化。在单因子实验的基础上使用Plackett-Burman法对碳源、氮源和无机盐进行产酶显著性分析, 培养基组分对β-葡萄糖苷酶生产影响的排序为: 气爆秸秆粉(TCS)>KH2PO4>黄豆饼粉(SM)=(NH4)2SO4。响应面模型结果表明最优培养基为: TCS 25.72 g/L, SM 6.82 g/L, KH2PO4 1.90 g/L, (NH4)2SO4 3.21 g/L, 其余成分保持原始浓度。在30 °C发酵8 d, β-葡萄糖苷酶的活性可以达到2.21 U/mL。     

谷氨酸棒状杆菌发酵生产L-瓜氨酸及发酵条件优化

以代谢控制发酵理论为指导,重点对C.glutamicum 366菌株进行摇瓶发酵条件的优化。应用响应面法优化发酵培养基的配比,优化后的发酵培养基:葡萄糖63.33 g/L、精氨酸196.96 mg/L、(NH4)2SO445.79 g/L、生物素35.72μg/L、K2HPO4·3H2O 1.0 g/L、KH2PO41.0 g/L、Mg SO4·7H2O、0.25 g/L、Mn SO4·H2O 0.02 g/L、Fe SO4·7H2O 0.02g/L、Zn Cl21 mg/L、Cu SO40.2 mg/L、VB1200μg/L、Ca CO330 g/L。摇瓶发酵培养条件:温度30℃、摇床转速200r/min、初始p H 7.0。在此发酵条件下,菌株进行摇瓶发酵72 h,产L-瓜氨酸14.96 g/L,相比优化之前提高了75.8%。     

L-色氨酸基因工程菌发酵培养基配方优化研究

[目的]对L-色氨酸基因工程菌液态发酵的培养基进行优化。[方法]通过P-B试验,筛选出对基础发酵培养基的发酵液中L-色氨酸浓度影响显著的因素,进一步通过最陡爬坡试验、B-B试验对影响显著的因素进行优化。在此基础上,确定最佳的发酵培养基配方。[结果]酵母粉、Fe SO4·7H2O、KH2PO4对发酵液中L-色氨酸浓度的影响显著;最佳培养基配方为:Glucose 25.0 g/L,酵母粉4.5 g/L,(NH4)2SO49.0 g/L,Mg SO44.5 g/L,柠檬酸钠2.0 g/L,Fe SO4·7H2O 96.1 m g/L,KH2PO41.2 g/L。[结论]根据此配方进行验证实验,发酵液中L-色氨酸浓度可达2.25 g/L。     

固定化微绿球藻去除NH4+-N、PO43——P效果的研究

为了探究固定化微绿球藻（Nannochloropsis oculata）去除污水中NH4+-N、PO43--P的效果,采用海藻酸钠固定化包埋技术进行实验。开展了固定化藻球大小、藻细胞包埋密度、藻球投放质量及充气培养条件对NH4+-N、PO43--P去除效果的单因子试验研究。结果表明,固定化藻球大小、藻细胞包埋密度、藻球投放质量和充气培养条件对NH4+-N、PO43--P的去除效果影响显著（P0.05）。藻球直径3.5 mm时生长速率（K）值最大（0.3320.002）,同时NH4+-N、PO43--P去除率效果最佳,分别为（75.083.83）%和（80.803.81）%;藻细胞包埋密度100104 cells/ball时K值最大（0.3300.033）,而NH4+-N、PO43--P去除率则以藻细胞包埋密度300104 cells/ball组为佳,分别达（87.200.43）%和（82.581.72）%,但考虑单位藻细胞去除率,包埋密度以100104 cells/ball为宜;随着藻球用量的增加K值下降,10 g/L组K值最大（0.3010.02）、50 g/L组K值最小（0.1930.01）,投放量30和50 g/L时NH4+-N去除率较高分别为（84.120.78）%和（84.630.45）%,30 g/L组PO43--P去除率最高达（77.131.43）%。综合考虑,藻球投放量选用30 g/L为宜;充气条件培养K值、NH4+-N和PO43--P去除率显著（P0.05）高于不充气,K值分别为（0.3060.006）和（0.1770.010）;NH4+-N去除率分别为（85.930.45）%和（49.320.45）%;PO43--P去除率分别为（66.665.00）%和（46.292.12）%。研究优化了微绿球藻固定化条件:固定化微绿球藻应进行充气培养,藻球规格3.5 mm、藻细胞包埋密度100104 cells/ball、藻球投放量30 g/L。     

黄芩愈伤组织培养条件的研究

在暗培养条件下,黄芩愈伤组织生长和次级代谢物合成的最佳培养条件:在基本培养基MS中氮源浓度为60mmol/L(NH4 ∶NO3-为1∶1),KH2PO41.5mmol/L,附加80g/L蔗糖,0.3mg/LIAA、2mg/L6-BA和200mg/L蛋白胨,(25±1)℃。培养40d后收获愈伤组织生物量达28.7g/L,总黄酮的含量为354.6mg/g,黄芩苷的含量为167.4mg/g。并发现蔗糖作为一种最佳碳源,在黄芩次级代谢物合成过程中起着至关重要的作用。     

L-缬氨酸发酵条件的研究

报道了L 缬氨酸高产菌XQ 6(Leu1AHVrα ABhr2 TAhr)摇瓶发酵条件的研究结果。试验结果表明 ,当发酵培养基中葡萄糖、(NH4 ) 2 SO4 、KH2 PO4 、MgSO4 ·H2 O、玉米浆和生物素的最适用量分别为 1 4 %、5 %、0 .1 %、0 .0 5 %、0 .5 %和2 5 μg/L时 ,经发酵培养 72h ,L 缬氨酸积累可达 5 8g/L ,最高为 62g/L。     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418