Purification, Immobilization and Characterization of Lipase Isoenzyme from <i>Aspergillus niger</i>with C8 Magnetic Particles

The purification of a lipase isoenzyme from an Aspergillus niger lipase A is reported in this manuscript. Purification was carried out in a simple adsorption step, in which the lipase was offered at low ionic strength to the commercially available C8 modified magnetic particles, MaKProt C8. When the isoenzyme was desorbed with a 0.2% solution of Triton X-100, the SDS-PAGE gel showed a single pure band with a molecular weight of 35 KDa. The purified fraction showed 66.75-fold purification compared with the crude extract. The pure fraction was characterized along with the crude extract and the lipase adsorbed on the MaKProt C8. The purified and the adsorbed lipase showed better activity for the tested substrates (p-nitrophenyl acetate, decanoate, myristate and palmitate) than the crude extract, the preferred substrates being myristate (26.7 μmol·min-1·mg-1) and decanoate (17.4 μmol·min-1·mg-1), respectively. The temperature and pH profiles showed no change for the three enzymes, the optimum temperature being 37°C and the best pH 7.0.

Partial purification,immobilization and preliminary biochemical characterization of lipases from Rhizomucor pusillus

Lipases have important applications in biotechnological processes, motivating us to produce, purify, immobilize and perform a biochemical characterization of the lipase from Rhizomucor pusillus. The fungus was cultivated by solid state fermentation producing lipolytic activity of about 0.5 U/mL(4U/g). A partial purification by gel filtration chromatography in Se-phacryl S-100 allowed obtaining a yield of about 85% and a purification factor of 5.7. Our results revealed that the purified enzyme is very stable with some significant differences in its properties when compared to crude extract. The crude enzyme extract has an optimum pH and temperature of 7.5 ° C and 40 ° C, respectively. After purification, a shift of the optimum pH from 7 to 8 was observed, as well as a rise in optimumtemperature to 60 ° C and an increase in stability. The enzyme was immobilized on CNBr-Agarose and Octyl-Agarose supports, having the highest immobilization yield of 94% in the second resin. The major advantage of immobilization in hydrophobic media such as Octyl is in its hyper activation, which in this case was over 200%, a very interesting finding. Another advantage of this type of immobilization is the possibility of using the derivatives in biotechnological applications, such as in oil enriched with omega-3 as the results obtained in this study display the hydrolysis of 40% EPA and 7% DHA from sardine oil, promising results compared to the literature.

Direct Ethylene Purification from Cracking Gas via a Metal–Organic Framework Through Pore Geometry Fitting

The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied for precise regulation of the pore geometry of four tailor-made metal–organic frameworks(MOFs)with pillar-layered structures,dubbed TYUT-10/11/12/13.Based on its pore geometry design and functional group regulation,TYUT-12 exhibits exceptional selective adsorption selectivity toward C_(3)H_(8),C_(3)H_(6),C_(2)H_(6),C_(2)H_(2),and CO_(2) over C_(2)H_(4);its C_(2)H_(6)/C_(2)H_(4) adsorption selectivity reaches 4.56,surpassing the record value of 4.4 by Fe_(2)(O_(2))(dobdc)(dobdc^(4-)=2,5-dioxido-1,4-benzenedicarboxylate).The weak p–p stacking binding affinity toward C_(2)H_(4) in TYUT-12 is clearly demonstrated through a combination of neutron powder diffraction measurements and theoretical calculations.Breakthrough experiments demonstrate that C_(2)H_(4) can be directly obtained from binary,ternary,quaternary,and six-component light hydrocarbon mixtures with over 99.95%purity.

Mathematical Simulation of Blood Purification for Leukemia by Immobilized L-asparaginase

Plasma was purified in an immobilized L-asparaginase column. The predicted results are in good agreement with experimental data. It is indicated that the mathematical model is suitable for the mass transfer and reaction of blood purification.

LC-MS/MS method for the quantitation of serum tocilizumab in rheumatoid arthritis patients using rapid tryptic digestion without IgG purification

The quantitation of serum tocilizumab using liquid chromatography tandem-mass spectrometry(LC-MS/MS)method has not been widely applied in clinical settings because of its time-consuming and costly sample pretreatments.The present study aimed to develop a validated LC-MS/MS method for detecting serum tocilizumab by utilizing immobilized trypsin without an immunoglobulin G purification step and evaluate its applicability in the treatment of rheumatoid arthritis(RA)patients administered intravenously or subcutaneously with tocilizumab.The tocilizumab-derived signature peptide was deciphered using a nano-LC system coupled to a hybrid quadrupole-orbitrap mass spectrometer.The serum tocilizumab was rapidly digested by immobilized trypsin for 30 min.The chromatographic peak of the signature peptide and that of the internal standard were separated from the serum digests for a total run time of 15 min.The calibration curve of serum tocilizumab concentration was linear with a range of 2-200 μg/mL.The intra-and inter-day accuracy and relative standard deviation(RSD)were 90.7%-109.4%and<10%,respectively.The serum tocilizumab concentrations in the RA patients receiving intravenous and subcutaneous injections were 5.8-28.9 and 2.4-63.5 μg/mL,respectively.The serum tocilizumab concentrations using the current method positively correlated with those using the enzyme-linked immunosorbent assay,although a systematic error was observed between these methods.In conclusion,a validated LC-MS/MS method with minimal sample pretreatments for monitoring serum tocilizumab concentrations in RA patients was developed.

Purification and Characterisation of a Coffee Pulp Tannase Produced by Penicillium verrucosum

Tannase was extracted from a new fungal strain Penicillium verrucosum using coffee pulp as a substrate by solid state fermentation. The extracellular tannase was purified using Sephadex G-100 to 86.02 folds with 34.3% yield and a single band corresponding to 81 kDa was observed in SDS-PAGE. Tannase was immobilized on alginate by entrapment method. The graphical analysis of the effect of the substrate concentration on the tannase activity yielded a Km of 48.88 mM and a Vmax of 169.49 U/mL. The optimum temperature and pH of the enzyme were 30 ℃ and pH 5. The thermal stability, as well as stability over a wide range ofpH, was significantly improved by the immobilization process. The activity was enhanced by Mg^2＋ （23.5%） and K^＋ （5.3%）, whereas Zn^2＋, Cu^2＋, Ca^2＋, NH^4＋ and Hg^2＋ inhibited tannase activity. Maximum substrate bioconversion （58.94%） from tannic acid to gallic acid and tea cream solubilisation （32.82%） was achieved using immobilized tannase. The extracellular tannase produced by P. verrucosum showed distinctive characteristics such as monomeric structure and activation by Mg^2＋, suggesting a new kind of fungal tannase with biotechnological potential.

One-step ethylene separation from ternary C_(2) hydrocarbon mixture with a robust zirconium metal-organic framework

One-step separation of high-purity ethylene(C_(2)H_(4))from C_(2) hydrocarbon mixture is critical but challenging because of the very similar molecular sizes and physical properties of C_(2)H_(4),ethane(C_(2)H_(6)),and acetylene(C_(2)H_(2)).Herein,we report a robust zirconium metal-organic framework(MOF)Zr-TCA(H3TCA=4,4',4"-tricarboxytriphenylamine)with suitable pore size(0.6 nm×0.7 nm)and pore environment for direct C_(2)H_(4) purification from C_(2)H_(4)/C_(2)H_(2)/C_(2)H_(6) gas-mixture.Computational studies indicate that the abundant oxygen atoms and non-polar phenyl rings created favorable pore environments for the preferential binding of C_(2)H_(2) and C_(2)H_(6) over C_(2)H_(4).As a result,Zr-TCA exhibits not only high C_(2)H_(6)(2.28 mmol·g^(-1))and C_(2)H_(2)(2.78 mmol·g^(-1))adsorption capacity but also excellent C_(2)H_(6)/C_(2)H_(4)(2.72)and C_(2)H_(2)/C_(2)H_(4)(5.64)selectivity,surpassing most of one-step C_(2)H_(4) purification MOF materials.Dynamic breakthrough experiments confirm that Zr-TCA can produce high-purity C_(2)H_(4)(>99.9%)from a ternary gas mixture(1/9/90 C_(2)H_(2)/C_(2)H_(6)/C_(2)H_(4))in a single step with a high C_(2)H_(4) productivity of 5.61 L·kg^(-1).

净水污泥固定化硫氧化菌去除河道中AVS污染的试验研究

目的 研究净水污泥固定化硫氧化菌去除河道中的酸可挥发性硫化物污染方法,为净水污泥资源化利用提供一种新的思路。方法 通过高温焙烧的方法制备净水污泥固定化载体,采用XRD、SEM、BET对载体进行表征,使用净水污泥、绿沸石、活性炭3种载体对硫氧化菌进行固定化,分析其对底泥中AVS的去除效果以及固定化效果的影响,并通过高通量测序技术分析其对微生物种群变化的影响。结果 净水污泥固定化载体的最佳焙烧温度为600℃,无论是单一载体,还是固定化硫氧化菌,净水污泥组对于AVS的去除效果均要优于绿沸石和活性炭;同时硫氧化菌在温度为30℃、pH=6、固定化时间为24 h条件下的固定化效果最好;净水污泥固定化硫氧化菌的加入有利于降解硫化物优势菌种的群居,抑制了硫酸盐还原菌的生长繁殖。结论 净水污泥固定化硫氧化菌能有效去除河道中的AVS污染,降低底泥生物种群的多样性,有利于去除AVS优势菌种的群聚,抑制硫酸盐还原菌的繁殖,促进水体黑臭环境的改善。

新型微生物包埋颗粒固定化技术降解甲醛的研究

传统的甲醛去除方法效率低、易致二次污染,微生物法则操作复杂、易受环境影响。固定化微生物技术有生物量浓度高、处理效率高、条件简易等诸多优点。本实验对以甲醛为唯一碳源的微生物进行培养和鉴定,采用反复冻融聚乙烯醇和海藻酸钠制作包埋颗粒,评估其降解效果。在9天的降解后,经筛选培养的微生物包埋颗粒使甲醛含量降至初始值的52.1%。本研究通过固定化生物技术降解室内甲醛,在兼顾环保的同时提高了甲醛降解的效率和稳定性。

固定化栅藻对污水的净化及其生理特征的变化

将斜生栅藻包埋固定在褐藻酸钙凝胶胶珠中。对人工配制的污水进行净化，研究其对污水中氨氮和正磷酸盐的净化效率以及净化过程中藻类的生长，叶绿素α含量、光合强度和过氧化物酶活性的变化。并与未固定的斜生栅藻（悬浮藻）进行对照比较，结果表明，由于固定化提高了斜生栅藻的合成代谢生理活性，延迟衰老。

利用微生物净水研究进展

近年来中国近海渔业水域环境污染和生物栖息生境破坏现象日益严重,海水富营养化程度趋势加剧,严重影响了海洋生态平衡,据调查,氮、磷(N、P)污染是造成海水富营养化的主要因素。微生物作为水域生态系统中的分解者,可对富营养化物质进行分解、吸收,驱动着水体中氮、磷等元素的生物化学循环。利用微生物净水技术和其他技术相结合的新型技术在研究和实践中被广泛应用,将微生物净水技术广泛应用于富营养化海域,是一种有效的防止海水富营养化措施。对国内外微生物净水的研究进展进行综述,以期为近海富营养化渔业水域的微生物净化、海洋生态修复和近海渔业发展提供参考。

烟草多酚氧化酶的分离与固定化技术研究

Polyphenol oxidase was purified from leaves of Nicotiana tobaccum and the needle shape crystals were formed. The enzyme was immobilized on nylon membrane with glutaraldehyde as the cross linking agent. The appropriate conditions for immobilization were as follows: (1) The concentration of enzyme, 13 5 U/ml (concentration of protein: 0 03 mg/ml); (2) The optimum time for cross linking by glutaraldehyde was 20 minutes; (3)The optimum time for immobilization was 7 hours; (4) The optimum concentration of glutaraldehyde was 0 25%; (5) The optimum temperature was 4℃. The activity of immobilized enzyme reached 35—40 U/g matrix, and the activity recovery was 76 2% and the coupling efficiency was 76 3%. The stability of immobilized enzyme under acid, basic and high temperature conditions were enhanced and shifted toward basic pH range. It will be beneficial for industrial utilization.

固定化小球藻净化污水的初步研究

采用褐藻酸钙凝胶包埋固定普通小球藻，对人工配制的污水进行静态模拟净化实验，研究了普通小球藻在固定和悬浮状态下，对污水中氨氮、正磷酸盐及重金属汞的净化效率。结果表明，固定化小球藻的净化效率比悬浮态要高得多，固定化小球藻对汞毒性的抗性亦较悬浮态强，在对悬浮藻有致死作用的汞浓度条件下仍具较高净化效率，同时分析了不同浓度的汞对其净化效率的影响。

Hg^（2＋）对固定化小球藻污水净化及生理特征的影响

利用褐藻酸钙凝胶包埋固定普通小球藻，对人工配制的含汞污水进行静态净化实验。研究了不同浓度Ｈｇ（２＋）对固定化小球藻净化污水中氨氮、正磷酸盐的效率及其４个生理指标（叶绿素ａ、光合强度、生长和过氧化物酶）的影响，并与悬浮藻对照比较。结果表明；由于小球藻的固定化增加了对Ｈｇ（２＋）毒性的抗性，０．２×１０（－６）浓度的Ｈｇ（２＋）对其净化效率无多大影响，而悬浮藻的净化效率明显下降。随着Ｈｇ（２＋）浓度的增加，；固定藻的净化效率逐渐下降，但其净化效率仍高于不含Ｈｇ（２＋）污水中悬浮藻的净化效率、且固定藻的生长、叶绿素ａ含量、光合强度和过氧化物酶活性与悬浮藻一样随Ｈｇ（２＋）浓度的增加而降低，但较悬浮藻高。

纳米TiO_2光催化剂负载技术研究

纳米TiO2 光催化剂在废水处理、空气净化等环保领域具有诱人的应用前景 ,将其负载于一定的载体上 ,并设计出高效的光反应器是其实用化的关键之一。本文对纳米TiO2 光催化剂负载所用载体、固定方法及其效果。

固定化微生物-水生生物强化系统在前置库示范工程中的应用

在前置库中构建固定化微生物-水生生物强化系统处理太湖入湖河道污水，以减少入湖污染负荷．在驯化期加入复合微生物菌剂30mg／kg，驯化期后每月投加1次（20mg／kg），强化微生物的活性．监测期间（5-11月）库水进水ρ（TN）为0．54～1．59mg／L，ρ（TP）为0．079～0．172mg／L，ρ（CODMn）为5．41—13．40mg／L，前置库水力停留时间约为9d，TN，TP和CODMn平均去除率分别为45．0％，42．2％和50．8％．固定化微生物区域微生物数量高于水生植物根际区1—2个数量级，反硝化菌数量达到10^9，水生植物根区微生物数量也高于示范区自然水体2～3个数量级以上．试验结果表明，固定化微生物-水生生物强化系统具有良好的环境适应能力，治理水体富营养化效果明显，但其在前置库中的长效运行，有待于进一步验证．

洋葱伯克霍尔德菌脂肪酶:一种应用前景广阔的生物催化剂

洋葱伯克霍尔德菌脂肪酶对有机溶剂(醇)、热、氧化剂、表面活性剂、去污剂、蛋白酶等具有良好的抗性,在有机合成、对映体拆分、非水相催化等领域应用十分广泛。综述了洋葱伯克霍尔德菌脂肪酶的发酵生产、分离纯化、基因克隆与表达、固定化与生物印迹、蛋白质结构解析及应用研究等,并展望了其未来发展方向,以期为该工业酶的研发与广泛应用提供参考。

固定化光合细菌净化养鱼水质试验

净化模拟养殖水质试验表明，固定化光合细菌可显著提高ＮＨ＋４ － Ｎ 和ＣＯＤ 的去除率，并能增加溶解氧。经１ 个月的鱼种饲养试验，固定化光合细菌（ Ⅲ组） 和游离光合细菌（ Ⅱ组） 鱼体重显著大于对照（ Ⅰ组） ，成活率也高于Ⅰ组。Ⅲ组效果最佳，不仅鱼体质好，活泼，个体较大且整齐，而且体色鲜艳。从水质分析结果看，Ⅲ组明显优于其它各组。

固定化微生物菌剂与蕹菜对中华鳖养殖污水的净化效果研究

为解决中华鳖(Trionyx sinensis)养殖所造成的水环境污染问题,研究利用海藻酸钠、沸石对复合光合菌剂和枯草芽孢杆菌菌剂分别进行固定化,并研究了不同固定化微生物菌剂与蕹菜对中华鳖养殖污水的净化效果。结果表明:净化处理15d后,利用固定化微生物菌剂与蕹菜共同处理组对中华鳖养殖污水的净化处理效果最好,养殖污水的CODMn、NH 4+-N、NO3-N、NO 2-N、PO34的去除率分别为88.7%、87.3%、90.8%、98.3%、74.9%。蕹菜处理组对于NO3-N、NO 2-N、NH 4+-N的去除率显著高于固定化复合光合菌剂处理组和固定化枯草芽孢杆菌处理组。固定化复合光合菌剂处理组对于NO3-N、NO 2-N、NH 4+-N的去除率显著高于固定化枯草芽孢杆菌菌剂处理组,但固定化枯草芽孢杆菌处理组对于污水的CODMn的去除率最高,可达90.6%。

单宁酶的性质与应用研究进展

单宁酶,又称单宁酯酰水解酶(Tannase,EC 3.1.1.20),可水解没食子酸单宁中的酯键和缩酚羧键,生成没食子酸和葡萄糖,单宁酶在自然界中分布广泛,主要用于食品工业、精细化工等领域。并综述了单宁酶研究与应用的最新进展。