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1.
Gentle alternatives to existing sterilization methods are called for by rapid advances in biomedical technologies. Supercritical fluid technologies have found applications in a wide range of areas and have been explored for use in the inactivation of medical contaminants. In particular, supercritical CO(2) is appealing for sterilization due to the ease at which the supercritical state is attained, the non-reactive nature, and the ability to readily penetrate substrates. However, rapid inactivation of bacterial endospores has proven a barrier to the use of this technology for effective terminal sterilization. We report the development of a supercritical CO(2) based sterilization process capable of achieving rapid inactivation of bacterial endospores while in terminal packaging. Moreover, this process is gentle; as the morphology, ultrastructure, and protein profiles of inactivated microbes are maintained. These properties of the sterilization process suit it for possible use on a wide range of biomedical products including: materials derived from animal tissues, protein based therapies, and other sensitive medical products requiring gentle terminal sterilization. 相似文献
2.
Supercritical carbon dioxide (SC-CO2) was used to inactivate fungal spores of Alternaria brassicicola. The inactivation conditions were optimized using response surface methodology (RSM). When the SC-CO2-entrainer (ethanol) system was applied to fungal spores, the treatment time required for the complete inactivation of fungal spores was substantially reduced. 相似文献
3.
Hyun-Song Lee Woo Gi Lee Sang-Woo Park Huen Lee Ho Nam Chang 《Biotechnology Techniques》1993,7(4):267-270
Summary The enzymatic hydrolysis reaction with supercritical carbon dioxide(SC-CO2) as a reaction medium to make glucose from starch was investigated. The reaction rate was enhanced at higher temperature and pressure, especially near the critical point of the CO2. The -amylase and glucoamylase were found to be active in a SC-CO2. 相似文献
4.
Resistance and recovery studies on ultraviolet-irradiated spores of Bacillus pumilus. 总被引:1,自引:1,他引:0
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A spore suspension model and a procedure for recovering ultraviolet (UV)-irradiated spores of Bacillus pumilus were investigated. A most-probable-number tube dilution method using double-strength Trypticase soy broth was found to be superior to the agar plate method for recovering optimal numbers of spores irradiated with sublethal doses of UV energy. Aqueous suspensions of B. pumilus survived UV doses up to 108,000 ergs/mm2 as determined by a most-probable-number recovery and estimation procedure. Resistance and stability data were consistent and reproducible, indicating the dependability of this method for recovering UV-damaged spores. The procedures used to collect information concerning resistance characteristics for two strains of B. pumilus are discussed. 相似文献
5.
In-Il Jung Seoungjoo Haam Giobin Lim Jong-Hoon Ryu 《Biotechnology and Bioprocess Engineering》2012,17(1):185-194
In this study, peptide-loaded microparticles were prepared using an aerosol solvent extraction system (ASES) by employing
supercritical carbon dioxide as an antisolvent. The effects of the molecular weight of poly(Llactide) (PLLA), poly(ethylene
glycol) (PEG), the block length of methoxy poly(ethylene glycol)-b-poly(L-lactide) (mPEG-PLLA), the blending of PLLA and PEG, and the drug-to-polymer feed ratio on the formation of leuprolide
acetate (LA)-loaded microparticles and their release characteristics were investigated. Scanning electron microscope observations
showed that the LA-loaded polymer particles had a spherical morphology with a smooth surface. The entrapment efficiency of
LA in the ASES-processed microparticles was found to be extremely high (about 99%), whereas the initial release rate of the
LA-loaded microparticles was very low for PLLA. The release rate of LA was observed to increase as the PEG block length of
mPEG-PLLA and/or the drug content in the microparticles increased. When PLLA was blended with PEG, the release rate of LA
from the PLLA/PEG microparticles was significantly faster compared with the corresponding mPEG-PLLA copolymer. 相似文献
6.
D-values of Bacillus pumilus spores on irradiated devices (inoculated product). 总被引:1,自引:1,他引:0
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H N Prince 《Applied microbiology》1978,36(2):392-393
The D-values of Bacillus pumilus spores on various devices ranged from 0.14 to 0.23 Mrads. The majority of devices displayed D-values equal to or less than the value obtained on filter paper. Increased resistivity was also encountered. 相似文献
7.
Summary Subtilisin Carlsberg was found to catalyze transesterification between N-acetyl-L-phenylalanine chloroethyl ester and ethanol in supercritical carbon dioxide. The effects of different temperatures and carbon dioxide/ethanol ratios on the reaction rate were investigated. A comparative study showed that enzymatic transesterification is faster in supercritical carbon dioxide than in anhydrous organic solvents. 相似文献
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9.
Production of micronic particles of biocompatible polymer using supercritical carbon dioxide 总被引:6,自引:0,他引:6
Three micronization techniques, based on the use of supercritical carbon dioxide, were investigated to produce microspheres of a natural biocompatible polysaccharide. Particles smaller than 20 mum were obtained by means of the rapid expansion of a supercritical solution method (RESS), both with and without cosolvents. The mean diameter of the particles was reduced to about 0.5 mum when a solution of the polymer in an organic solvent was expanded by using carbon dioxide as a supercritical antisolvent (SAS). The SAS process was operated both in a continuous and in a batch mode. The former leads to aggregated structures and fibers, and the latter to the formation of micronic spherical particles. It was found that the experimental temperature did not substantially affect the shape and dimension of the particles. A stronger dependence is shown with respect to the solute concentration in the starting solution. The proposed method is attractive as the basis of a new process for the preparation of drug delivery systems. (c) 1997 John Wiley & Sons, Inc. 相似文献
10.
Huen Lee Won-Hi Hong Ji-Ho Yoon Kyu-Min Song Sang-Soo Kwak Jang-Ryol Liu 《Biotechnology Techniques》1992,6(2):127-130
Summary Indole alkaloids, particularly vindoline and catharanthine, were extracted from the leaves ofCatharanthus roseus by supercritical extraction with CO2. The contents of vindoline and catharanthine in the extracts were determined by HPLC and identified by LC/MS. About 52 %(w/w)
of the initial vindoline content, 1.5 mg vindoline/g dry wt leaves, was recovered after extracting this material for 10 h
with the CO2 flow rate of 400 ml/min at 40°C and 150 bar. Vindoline concentration in the extract was 67 %(w/w). 相似文献
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12.
Investigations of enzymatic reactions in supercritical CO(2) are often hindered by the high pressure involved in these processes, making reaction monitoring extremely difficult. This paper describes the implementation of a fiber optic based oxygen sensor into a high pressure reactor for supercritical carbon dioxide. The sensor is pressure resistant, working in supercritical carbon dioxide and reusable after depressurisation. The sensor signal is found to be affected by pressure changes, but stable at constant pressure. Oxygen concentration in supercritical CO(2) is monitored using the disproportionation of hydrogen peroxide as a simple oxygen producing reaction. 相似文献
13.
The survival of Bacillus pumilus SAFR-032 spores to standard industrial clean room sterilization practices necessitates the development of rapid molecular diagnostic tool(s) for detection and enumeration of viable bacterial spores in industrial clean room environments. This is of importance to maintaining the sterility of clean room processing products. This paper describes the effect of propidium monoazide (PMA) on fluorescence in situ hybridization (FISH) for detecting and enumerating B. pumilus SAFR-032 viable spores having been artificially encapsulated within poly(methylmethacrylate) (Lucite, Plexiglas) and released via an organic solvent (PolyGone-500). The results of the PMA-FISH experiments discussed herein indicate that PMA was able to permeate only the compromised coat layers of non-viable spores, identifying PMA treatment of bacterial spores prior to FISH analysis as a novel method for selecting out the fraction of the spore population that is non-viable from fluorescence detection. The ability of novel PMA-FISH to selectively distinguish and enumerate only the living spores present in a sample is of potential significance for development of improved strategies to minimize spore-specific microbial burden in a given environment. 相似文献
14.
Monocrotaline, a pyrrolizidine alkaloid of chemotherapeutic interest, was successfully extracted from the crushed seeds of Crotalaria spectabilis using supercritical carbon dioxide and ethanol mixtures. Overall solubilities of the plant material in the supercritical fluid phase were as high as 1.1 mass percent, and monocrotaline solubilities were as high as 0.07 mass percent. The solubility of monocrotaline in the presence of other plant material was smaller by 50 to 98% compared with the solubility of pure monocrotaline in the supercritical fluid. Also, it was found that the extraction of the complex plant material was time-dependent after approximately one percent of the original mass of the material had been extracted. 相似文献
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Hyung-Seob Roh Ji-Yeon Park Sun-Young Park Byung-Soo Chun 《Biotechnology and Bioprocess Engineering》2006,11(6):496-502
Off-flavors and unfavorable odors in tuna fish oil were successfully removed and identified using supercritical carbon dioxide
extraction, while retaining variable compounds, polyunsaturated fatty acids such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic
acid). Samples of oil were extracted in a 100 mL semi-batch stainless steel vessel under conditions which ranged from 8 to
20 MPa and 20 to 60°C with solvent (CO2) flows from 10 g/min. GC-MS was used to identify the main volatile components contributing to the off-flavors and odors which
included 2-methyl-1-propanol, 2,4-hexadienal, cyclopropane, and octadiene. Analyses of oil extracted at 40°C, 20 MPa showed
a 99.8% reduction in dimethyl disulfide. Other significant off-flavors identified were 2-methyl-butene, 3-hydroxy butanal
and ethylbenzene. 相似文献
17.
Kil-Yoon Kang Dong-Hyun Ahn Sun-Mi Jung Dong-Hun Kim Byung-Soo Chun 《Biotechnology and Bioprocess Engineering》2005,10(4):315-321
Supercritical carbon dioxide extraction was investigated as a method for removing lipids and bad flavor from tuna viscera.
To find the optimum conditions, different experimental variables, such as pressure, temperature, flow rate of solvent and
sample size, were evaluated for the effective removal of lipids and the undesirable smell. Ethanol was used as the entrainer,
with a 3% by vol CO2 flow rate. By increasing the pressure at constant temperature, the efficiency of the lipid removal was improved and the protein
was concentrated without denaturalization. The main fatty acids extracted from the tuna viscera were palmitic acid (16∶0),
heptadecanoic acid (17∶1), oleic acid (18∶1) and docosahexaenoic acid (22∶6). The major amino acids in the tuna viscera treated
by supercritical carbon dioxide were glutamic acid, leucine and lysine, and the free amino acids werel-proline, taurine andl-α-aminoadipic acid. 相似文献
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19.
Dickinson DN La Duc MT Satomi M Winefordner JD Powell DH Venkateswaran K 《Journal of microbiological methods》2004,58(1):1-12
To verify the efficacy of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) protein profiling for identifying and differentiating bacterial species, several strains of Bacillus pumilus were examined in a thorough taxonomic study incorporating a polyphasic approach. Sixteen isolates of putative B. pumilus isolated from spacecraft assembly facilities, the Mars Odyssey spacecraft, and the International Space Station, were characterized for their biochemical and molecular profiles using the Biolog system, DNA techniques, and MALDI-TOFMS protein profiling. MALDI-TOFMS protein profiling was more accurate than Biolog metabolic profiling, more discriminating than 16S rDNA sequence analysis, and complemented the results of gyrB sequence analysis and DNA-DNA hybridization for the identification of the B. pumilus spores. This is the first report whereby MALDI-TOFMS generated protein profiles from a set of microbes is compared directly with DNA-DNA hybridization yielding a positive correlation. Unique, cluster-specific biomarker peaks have been identified in the spores of the B. pumilus examined in this study. MALDI-TOFMS protein profiling is a rapid and simple analysis and has been demonstrated as a useful taxonomic tool for differentiating spores of the genus Bacillus. For practical purposes, it would be ideal (and necessary) to have a publicly available, standardized MALDI profile database, to facilitate the use of the technique as a diagnostic method to differentiate bacterial species. 相似文献
20.
《Journal of liposome research》2013,23(4):334-346
AbstractA novel method for the production of non-ionic surfactant vesicles (niosomes) using an rapid expansion of supercritical solution (RESS)-based process coupled with a gas ejector is presented along with an investigation of parameters affecting niosome morphology, size and encapsulation efficiency of a 0.2?M d-glucose solution in Tris buffer at physiological pH. The solubility of the non-ionic surfactant polyoxyethylene(4) sorbitan monostearate in SC-CO2 was determined at three pressures (10, 15 and 20?MPa) and three temperatures (40, 50 and 60?°C). Mole fraction of Tween61 in the vapor phase increased with pressure at 40?°C, but did not change with pressure at 50 or 60?°C. Solubility data were correlated using the Peng–Robinson equation of state (PREOS) with the Panagiotopoulos and Reid mixing rule. Vesicles were either multilamellar or unilamellar, depending on the degree of precipitation of the lipid formulation at the point of aqueous cargo introduction. Vesicle particle size distributions were bimodal, with the 80–99% of the liposomal volume contributed niosomes ranging in size from 3 to 7?μm and the remaining niosomes ranging from 239 to 969?nm, depending on the system configuration. Encapsulation efficiency as high as 28% using the gas ejector to introduce the glucose cargo solution was achieved. Vesicle particle size and encapsulation efficiency were shown to be dependent on cargo droplet formation. 相似文献