摘要:

Abstractβ‐Amylase (EC 3.2.1.2), obtained from barley, was chemically attached to a crosslinked copolymer of acrylamide‐acrylic acid using a water‐soluble carbodiimide. The derivative showed 23% β‐amylase activity in relation to that of free enzyme with a coupling yield of 40% based on the amount of added β‐amylase. In order to find optimal coupling conditions, the effect of pH and different carbodiimide concentrations was investigated. The enzymic activity associated with different β‐amylase concentrations was further outlined. A slightly increased operational stability for the enzyme upon immobilization was observed. Markedly improved operational stability has been obtained by coupling in the presence of reduced glutathione of bovin

ISSN:0006-3592    

DOI:10.1002/bit.260160502

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

Abstractβ‐Amylase (EC 3.2.1.2) and pullulanase (EC 3.2.1.9) have been covalently bound in a two‐enzyme system to a crosslinked copolymer of acrylarmide‐acrylic acid by using a water‐soluble carbodiimide. The coupling yields based on the amounts of added β‐amylase and pullulanase were 40% and 38%, respectively, with residual enzymic activities of 22% and 32% of those of free enzymes. A markedly increased operational stability was observed for the immobilized two‐enzyme system compared to the free enzymes in solution. In order to find optimal operational conditions the influence of different pH values and temperatures on the conversion process was investigated. The action of the immobilized β‐amylase‐pullulanase derivative on partially hydrolyzed starch (DE 3.4–10.7) in a packed bed column was studied. Analysis of the product was performed using gas

ISSN:0006-3592    

DOI:10.1002/bit.260160503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractAn immunoadsorbent process has been devised for removing serum hepatitis antigen (HAA), from blood, blood plasma, and plasma products.The immunoadsorbent complexes specifically with HAA and the complex is removed from the plasma by filtration. The complex is dissociated with 0.23MNH4OH. The immunoadsorbant is regenerated for further processing, while the purified HAA by‐product my be used to produce more antibody in animals.The rate of complexing is such that HAA is reduced one log cycle each 2hr. Since available tests can only detect HAA to about 109particles per ml, it is proposed that HAA negative plasma and plasma products can be processed to reduce HAA to a probability of less than one HAA particle per plasma pool.A gibbon injected with infectious commercial Factor IX that was subjected to the immunoadsorbent process showed no sign of infection after 8 months. However 14 weeks after injection with unprocessed Factor IX, the gibbon showed signs of infectio

ISSN:0006-3592    

DOI:10.1002/bit.260160504

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractA new and simple method for immobilization of enzymes by the aerobic radio‐polymerization of acrylamide was developed. Irradiation treatment of acrylamide in the frozen state produces a spongy immobilized enzyme membrane without the addition of carriers. Aerobic polymerization yields of acrylamide in the frozen state were increased by the addition of starch and also by lyophilization.Glucose oxidase (activity recovery was 12.3–33.7%), invertase (69.2%),D‐amono acid oxidase (25.0–70.5%), aminoacylase (39.2–43.7%), mold α‐amylase (18.0%), malt β‐amylase (4.1%), glucoamylase (6.5%), alkaline protease (5.3%), and neutral protease (10.5%) were immobilized by this method. Invertase entrapped by this method had a wider optium pH range and was active at high

ISSN:0006-3592    

DOI:10.1002/bit.260160505

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractMaltase, phosphatase, malate dehydrogenase, glucose‐6‐phosphate dehydrogenase, and 6‐phosphogluconate dehydrogenase activities were determined in the supernatant of brewer's yeast cells from samples taken at various intervals during a 90 min treatment in a Dyno‐Mill disintegrator.In an attempt to find optimum operating conditions, the following parameters were varied: speed of rotation of the agitator, flow rate, yeast concentration in the slurry and bead diameter, and the specific rate of extraction was determined for each such variation. Analysis of the data showed that, superimposed upon extraction, there was a progressive but slow loss of total activities. Enzyme release could be expressed as an approximately first‐order chemical reaction. The results compared well with those of Follows et al. (Biotechnol. Bioeng.),13, 549 (1971) and showed that the Dyno‐Mill can be operated under proper conditions without significant loss of enzyme activity and with

ISSN:0006-3592    

DOI:10.1002/bit.260160506

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractCandida tropicaliswas cultured in a chemostat‐type fermentor withn‐hexadecane, dispersed in water as submicron droplets, as the only carbon substrate. The emulsion as well as the aqueous medium were fed continuously into the fermentor. A Monod‐type equation can correlate the specific group rate in the continuous fermentor with the concentration of submicron droplets. The same equation can also be fitted to the data for the conventional‐type batch culture in the same fermentor in which an oil phase as well as an aqueous phase existed, if the hydrocarbon concentration in the aqueous phase excluding oil drops is employed as the substrate concentration. This demonstrates thatCandida tropicalistakes up only submicron droplets ofn‐hexadecane as the carbon

ISSN:0006-3592    

DOI:10.1002/bit.260160507

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractThe time course of release of intact labile material from cells by cavitating ultrasound is examined. Curves are presented which show the yield of intact subcellular components obtainable from cells as a function of sonication time for various values of the ratio of inactivation rate to release rate. The general cases where inactivation of released product is concentration dependent (chemical) and concentration independent (mechanical) are considered.For a flow system the time of attainment of equilibrium concentration of active product is analyzed as a function of flow rate, release rate, inactivation rate, and volume of chamber. Curves of optimal yields to be expected for batch and flow systems are presented. It is shown that sonochemical inactivation can be made negligible by sonication of high cell concentration suspensions.

ISSN:0006-3592    

DOI:10.1002/bit.260160508

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractAmong the methods used for the rupture of cells by means of solid shear, the Hughes press is best known. It operates by forcing an aqueous suspension of cells previously frozen at −27°C under pressure through a narrow circumferential gap. The mode of action requires a knowledge of the isentropic compression of the solid phase and its possible involvement with a phase change from ice I to ice III. It is shown that the mechanical properties of the solid mixture are relevant. A model is proposed of the plastic flow for the geometry of the press and it is shown that cell breakage is proportional to the velocity of the plunger and inversely proportional to gap wid

ISSN:0006-3592    

DOI:10.1002/bit.260160509

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

摘要:

AbstractA soluble fungal lactase (lactase‐W) of greater activity that the previously available fungal lactase (lactase‐M) has been covalently coupled to ZrO2‐coated porous glass particles and 1 mm diameter porous TiO2particles. The immobilized lactase‐W appears to give results similar to the lactase‐M except for the operational half‐life. At 30°C the half‐life of the lactase‐M appears to exceed that of the lactase‐W by approximately 100 days under oper

ISSN:0006-3592    

DOI:10.1002/bit.260160510

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY

ISSN:0006-3592    

DOI:10.1002/bit.260160511

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1974

数据来源: WILEY