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SOFTWARE AND FILE STRUCTURES FOR COMPUTER-COUPLED PILOT FERMENTATION PLANTS
No full textSoftware and file structures are discussed which were successfully used to couple
six fermentation vessels to a process computer in a research pilot plant. Computer
program functions are described which performed the data processing, process operator
service, and communications in this installation. Also discussed are extensions
to the FORTRAN language which were used for process operator graphics and for communication
between the process computer and a time-sharing computer
Novel 2,4-disubstituted quinazoline analogs as antibacterial agents with improved cytotoxicity profile: Modification of the benzenoid part.
No full textBacterial resistance to currently used antibiotics demands the development of novel antibacterial agents with good safety margins and sufficient efficacy against multi-drug resistant isolates. We have previously described the synthesis of N-butyl-2-(butylthio)quinazolin-4-amine (I) as an optimized hit with broad-spectrum antibacterial activity and low cytotoxicity. In addition, we have identified a potential growing vector for this series of compounds. Herein, we describe further hit optimization which includes systematic diversifications of both the benzenoid part and the substituents at position 6 and 7 of compound I. Growing of the molecule beside the core modifications yielded several compounds with remarkable anti(myco)bacterial activity against a panel of pathogenic bacteria, including drug-resistant strains. Compound 12 showed a 2-4 fold improvement in activity than I against S. aureus Newman, S. pneumoniae DSM-20566 and E. faecalis DSM-20478. The compounds also showed a good safety profile towards human HepG2 cells
Towards the total synthesis of chondrochloren A: synthesis of the (Z)-enamide fragment.
No full textThe stereoselective synthesis of the (Z)-enamide fragment of chondrochloren (1) is described. A Buchwald-type coupling between amide 3 and (Z)-bromide 4 was used to generate the required fragment. The employed amide 3 comprising three chiral centers was obtained through a seven-step sequence starting from ᴅ-ribonic acid-1,4-lactone. The (Z)-vinyl bromide 4 is accessible in four steps from 4-hydroxybenzaldehyde. The pivotal cross coupling between both fragments was achieved after extensive experimentation with copper(I) iodide, K2CO3 and N,N'-dimethylethane-1,2-diamine
EINFACHPROZESS ZUR VERHEFUNG VON ULTRAFILTRATIONSPERMEAT VON MILCH UND MOLKE
No full textUpgrading of ultrafiltration permeate was carried out with the yeast
Trichosporon cutaneum, a strictly respiratory organism. The mineral
salts medium with urea as N-source was optimized taking into account
the content of minerals of the permeate. The optimization was done by
performing a X-S-diagram in continuous culture using permeate of
different dilution as substrate. The growth kinetics of T. cutaneum
on permeate were determined in batch cultures in a 30 1 bioreactor
at unsterile conditions. The upgrading process was further tested in
a 300 1 pilot plant with respect to yield, duration of growth and
stability of the culture. The costs of the process were evaluated and
compared to those arising from sewage disposal of the ultrafiltration
permeate
VERFAHRENSTECHNISCHE GRUNDLAGEN - EINFUHRUNG
No full textDie industrielle Erzeugung von Protein mittels Mikroorganismen steht
wie alle technischen Prozesse unter dem Zwang zur Wirtschaftlichkeit.
Unabhängig davon, ob es für die menschliche Ernährung oder als Viehfutter
verwendet werden soll, stellt Protein ein Veredelungsprodukt
dar; unter dem Gesichtspunkt der Wirtschaftlichkeit müssen die Ausgangsprodukte
billig und in hinreichender Menge verfügbar sein
PROTEINQUALITÄTSUNTERSUCHUNGEN MIT RATTEN AN EINEM BAKTERIELLEN SCP (METHYLOMONAS CLARA)
No full textEvaluation of protein quality with rats on a bacterial Sep!
Two samples of the single cell biomass and two extracted preparations
hereof were tested in digestibility trials, N-balance experiments and
growth studies with rats.
The digestibility of the nitrogen and the amino acids was comparable to
that in plant proteins of good quality but 5-10% lower than in casein.
The nucleic acid fraction, although highly digestible itself (calculated
from the difference between crude-and true-protein digestibility),
seemed to interfere with the digestibility of the true protein fraction.
The biological value was in spite of the dilution of the N-intake by the
nucleic acids considerably high (about 85) in the methionine supplemented
SCP.
In growth studies with young rats the SCP yielded relatively low weight
gains. Methionine supplementation improved the growth rate up to 80% of
the casein fed rats. A principal reason for the reduced development of
the animals however was a depression of the food intake which seemed
partially to be connected with the fine and dusty structure of the SCP
material.
In experiments with a granulated SCP a better food consumption and a
better performance were found but there were still differences compared
with the casein group namely in younger animals. The lower palatability
even of the granulated SCP could be eliminated by using an adaptation
period 4 days before the beginning of the experiment itself
DESIGN OF THE MAN-MACHINE INTERFACE FOR COMPUTER COUPLED FERMENTATION
No full textThree interfaces are identified in an industrial process computer system: the process/
instrumentation-computer interface, the power interface, and the man-machine interface.
The man-machine interface is further divided into three sub-interfaces: The plant operatorprocess
interface, the control room operator-automation system interface, and the process
engineer interface. The problems in designing man-machine interfaces and the results
from research work and practical experiments in human engineering are briefly discussed.
In chapters 4 and 5, the design of the man-machine interface is visualized by a short
introduction of the concepts realized in the pilot fermentor control system (PFCS), developed
by Rintekno Oy
EINFLUSS DER KONSTRUKTION UND PROZESSFÜHRUNG AUF DAS BETRIEBSVERHALTEN VON BLASENSÄULENREAKTOREN MIT ÄUSSERER SCHLAUFE
No full textCell growth and product formation as well as productivity of aerobic
cultivations are strongly influenced by the oxygen transfer rate.
Strategies for construction of effective tower reactors with an outer
loop and their operation were developed by means of measurements with
model media and cultivations of Hansenula polymorpha. The coalescence
behavior strongly influences this strategy.
For media with strong coalescence suppressing character a high energy
dissipation rate should be used in a limited volume near the aerator.
In coalescence promoting media, the energy dissipation rate should be
uniformly distributed along the column. When employing columns with
proper stage heights this strategy can be realized.
Antifoam additives significantly reduce the oxygen transfer rate. This
reduction can be overcompensated by using multistage columns with low
stage heights. Biomass productivity can be increased and specific power
input can be reduced in these reactors with regard to single-stage reactors
which are operated without antifoam agents
UNTERSUCHUNGEN ZUR SCHMACKHAFTIGKEIT SCP-HALTIGER DIÄTEN
No full textStudies on Palatability of SCP Diets.
In short-term two-choice preference tests with adult rats the palatability
of a diet containing 30 % SCP (Methylomonas clara, Hoechst AG,
Frankfurt) was compared with that of diets containing casein (24 %) as
protein source. Two casein diets were used. The palatability of one
casein diet had been reduced by addition of 4 % saccharoseoctaacetate
= SO).
Naive rats preferred the casein diet (without SO) against the SCP-diet
and the SCP-diet against the SO-diet. After feeding the SCP-diet for 3
days, the animals ate about the same amount of SCP- and casein-diet in
the short-term preference test. An analogous observation was made in
rats fed the SO-diet for 3 days. Unlike the naive rats these animals
also ate about the same amount of SO- and SCP-diet.
In a 2 week feeding trial with adult rats food intake and weight gain
did not differ markedly between the animals fed one of the three diets.
The results indicate that after a short period of adaptation rats accept
relatively unpalatable diets well