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1.
N. Čeřovská H. Hoffmeisterová T. Moravec H. Plchová J. Folwarczna R. Hadámková 《Biologia Plantarum》2008,52(1):184-186
We describe the optimized storage conditions of recombinant Potato virus A coat protein (ACP) carrying two different epitopes from Human papillomavirus type 16 (HPV-16). Epitope derived from minor capsid protein L2 was expressed as N-terminal fusion with ACP while an epitope
derived from E7 oncoprotein was fused to its C-termini. The construct was cloned into Potato X potexvirus (PVX) based vector and transiently expressed in plants using Agrobacterium tumefaciens mediated inoculation. The effect of storage conditions on the serological activity of L2ACPE7 was studied by ELISA using
IgG anti PVX, PVA and L2. Purified L2ACPE7 stored freeze-dried (at −20 °C), frozen at various temperatures (−20 °C, −70 °C)
and at +4 °C were tested. Purified L2ACPE7 was most stable as lyophilized material stored at −20 °C. Our study demonstrates
suitable way for the storage of plant material containing foreign viral epitopes for the purposes of edible vaccination. 相似文献
2.
Malcolm R. Brown 《Journal of applied phycology》1995,7(5):495-500
Microalgae concentrates, prepared by centrifuging axenic (bacteria-free) cultures of Chaetoceros calcitrans (Paulsen) Takano, were processed and stored under different experimental conditions. The content of ascorbic acid was examined
in the concentrates, to assess potential changes in their nutritional properties. In algae pastes stored at 4 °C, it reduced
by 29% after 4 weeks storage. As most of the ascorbic acid was retained intracellularly (92%) after resuspension, most of
the cells had remained intact. In frozen and dried paste preparations, the losses of ascorbic acid ranged from minor (11%
after liquid nitrogen storage for 4 weeks) to major (≥94% after drying at 100 °C for 2 h or at 60 °C overnight). However,
most of the remaining ascorbic acid (>85%) in these preparations was rapidly leached from cells upon resuspension. Therefore,
pastes stored at 4 °C may have the best potential as an ‘off-the-shelf’ microalgal food product for mariculture. Pastes should
now be assessed in animal feeding trials, before being recommended for widespread use in the industry. 相似文献
3.
Two temperate mushroom cultures namely Agaricus bisporus (U-3) and Pleurotus florida (PAU-5) were evaluated for their physiological (linear growth and biomass production), biochemical (β-1,4 endoglucanase production)
and fruiting behaviour after preservation in 10% (v/v) glycerol and storage at room temperature (25–35°C), −20°C and −196°C
for 6 months with the objective of establishing the recovery/changes in these fungi after storage. Studies indicated that
the viability and recovery of A. bisporus and P. florida is affected by the storage conditions. Both the fungi could be best stored in liquid nitrogen for longer durations but for
regular use, conventional sub-culturing was appropriate. 相似文献
4.
Fifteen species of marine invertebrate commonly occurring in the near-shore environment of Rothera base, Antarctica, were
used to test tissue sample storage protocols with regard to preservation of RNA integrity. After animal collection, the tissues
were either immediately extracted for RNA or stored at −80°C after having been, either directly flash frozen in liquid nitrogen
or preserved in a commercial RNA storage solution, for extraction in the UK. In four cases, direct flash freezing produced
enhanced RNA integrity compared with samples in the commercial storage solution. A subset of samples were further tested for
the preferred temperature of storage in the commercial reagent. RNA integrity was well preserved at both +4 and −20°C over
periods of 2 months, but degradation was rapid in tissues stored at room temperature. Eight out of the fifteen species only
produced a single ribosomal band on gel electrophoresis. This survey provides a guide for tissue transport of Polar cold water
marine invertebrates. 相似文献
5.
Objective: The most important factors of long term clinical performance of biological heart valve prostheses are methods of processing
and cryopreservation. That is why we decided to evaluate the impact of current Allograft Heart Valves (AHV) Bank protocol
on valve tissue morphology. Scanning electron microscope (SEM) is a valuable tool for investigation of biological surfaces.
In case of cardiac valves it is especially suitable for detection of fine changes in endothelial covering and underlying layers.
Material and methods: “Fresh” aortic and pulmonary AHV samples, harvested from “heart-beating” cadaveric donors, were compared with (1) tissue
from AHV obtained from non heart-beating donors, (2) samples stored in 4 °C saline for 24 h, (3) antibiotic treated tissue
for 24 h at 37 °C and finally (4) cryopreserved valves, stored in liquid nitrogen (−196 °C) for 6–38 months. All samples were
dissected, dried with hexamethyldisilazane (HMDS), gold coated, studied and photographed by SEM (Tesla BS 301). Results: Our alternative method of drying samples by the HMDS method proved to be suitable for thin membranes of human semilunar
valves. We were able to detect early changes in the endothelium after harvesting, and denudation of the endothelial covering
during preservation with and without freezing. Conclusion: SEM (using HMDS drying) along with other methods may be helpful for the morphological control of processing, cryopreservation
and liquid nitrogen storage of AHV. According to the current findings we have to avoid washing of AHV in saline after harvesting. 相似文献
6.
Influence of culture conditions such as light, temperature and C/N ratio was studied on growth of Haematococcus pluvialis and astaxanthin production. Light had significant effect on astaxanthin production and it varied with its intensity and direction
of illumination and effective culture ratio (ECR, volume of culture medium/volume of flask). A 6-fold increase in astaxanthin
production (37 mg/L) was achieved with 5.1468·107 erg·m−2·s−1 light intensity (high light, HL) at effective culture ratio of 0.13 compared to that at 0.52 ECR, while the difference in
the astaxanthin production was less than 2 — fold between the effective culture ratios at 1.6175·107 erg·m−2·s−1 light intensity (low light, LL). Multidirectional (three-directional) light illumination considerably enhanced the astaxanthin
production (4-fold) compared to unidirectional illumination. Cell count was high at low temperature (25 °C) while astaxanthin
content was high at 35 °C in both autotrophic and heterotrophic media. In a heterotrophic medium at low C/N ratio H. pluvialis growth was higher with prolonged vegetative phase, while high C/N ratio favoured early encystment and higher astaxanthin
formation. 相似文献
7.
B. J. O. Efiuvwevwere L. G. M. Gorris E. J. Smid E. P. W. Kets 《Applied microbiology and biotechnology》1999,51(1):100-104
Survival of Lactococcus lactis subjected to different drying conditions was investigated. Mannitol most remarkably enhanced the survival of dried cells
to a level almost equalling that of viable cells [log10 (cfu ml−1) = 9.42] as was found prior to the drying process (log10 = 9.6). In the absence of mannitol, a survival was reduced by a factor of 104. Drying of cells at 20 °C led to higher survival rates than drying at 30 °C. Mannitol enhanced the survival rate at both
temperatures, and at both 20 °C and 30 °C the highest reduction in survival occurred when cells were dried at a water activity
of 0.76. In the presence of mannitol, differences in survival after drying at different water activities were less pronounced.
Rehydration of cells dried in the presence of mannitol resulted in an extended lag phase of 4 h compared to fresh cells. No
growth or acidification of the culture medium was observed for 12 h in the case of rehydrated cells dried in the absence of
mannitol. It was hypothesized that a radical scavenging activity of mannitol could partly explain these observations.
Received: 28 August 1998 / Accepted: 2 October 1998 相似文献
8.
Powders of Dunaliella salina biomass were obtained by spray drying a cell concentrate under different drying regimes. A three-factor, two-level experimental
design was employed to investigate the influence of inlet temperature, outlet temperature and feed solids on β-carotene recovery. The effect of microencapsulation in a polymer matrix of maltodextrin and gum arabic was also studied.
All powders were stored under specific conditions to assess the stability of the native β-carotene. There was a trend indicating that lower outlet temperature yielded higher carotenoid recoveries, β-carotene recovery varying between 57% and 91%. Microencapsulated biomass yielded 100% recoveries. All non-microencapsulated
powders were unstable in terms of β-carotene content in the presence of natural light and oxygen showing 90% degradation over a 7-day period. The incorporation
of a microencapsulating agent had a significant increase in the storage stability. Results indicated a first-order degradation
of the β-carotene in microencapsulated powders with kinetic constants of 0.06 day−1 and 0.10 day−1. HPLC analysis showed no effect of drying processes on isomer composition (9-cis-β-carotene and all-trans-β-carotene ratio). This behaviour was also observed during storage of the microencapsulated powders.
Received 16 October 1996/ Accepted in revised form 13 November 1997 相似文献
9.
The multicolored Asian ladybird beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is considered an important generalist predator that can be used as a biological control
agent against Hemiptera Sternorrhyncha, Thysanoptera, and the eggs and larvae of Lepidoptera, Coleoptera and Diptera. There
are currently abundant natural resources of overwintering H. axyridis in Asia and North America. Given its potential as a biological control agent, methods can be developed to increase its effectiveness
for pest control. The availability of an adequate cold storage method would enable the use of field-collected pre-wintering
ladybirds for pest suppression in the following season. We studied the effect of cold storage (30, 60, 90, 120 and 150 days
stored at −3, 0, 3 and 6°C) on survival, fecundity and predation in field-collected populations. The survival of both female
and male ladybirds decreased significantly as storage duration increased at −3°C and 0°C. The ladybirds showed more than 80%
survival when they were stored for 150 days at 3°C and 6°C. Long-term cold storage had different effects on the fecundity
of H. axyridis at different temperatures. Prolonged cold storage at both 3°C and 6°C shortened pre-oviposition duration and had no adverse
effect on reproductive capacity as compared to that of unstored individuals. The adults that experienced 90-day storage at
0°C had the shortest pre-oviposition duration and the largest reproductive capacity. The individuals that were stored for
150 days at 3°C consumed significantly more aphids than the unstored ones. Generally, 3–6°C is a suitable temperature for
cold storage of the ladybird without any reduction in fitness. This study will help the exploitation and application of pre-wintering
H. axyridis for the biological control of insect pests. 相似文献
10.
M A Jackson J S Frymier B J Wilkinson P Zorner S Evans 《Journal of industrial microbiology & biotechnology》1998,21(4-5):237-241
Xanthomonas campestris MB245, a specific pathogen of the weedy grass Poa annua (annual bluegrass), is being developed as a bioherbicide to control this pest in turf. Nutritional and environmental factors
were evaluated based on their ability to support rapid submerged culture growth and high cell yield. Temperature optima for
the growth of X. campestris cells in submerged culture were between 27 and 30°C. At 30°C, optimal nutritional conditions for X. campestris growth supported generation times of 150–175 min and cell yields after 24 h growth of 1–2 × 1010 cells ml−1. Media containing sucrose or glucose as the carbon source and various organic nitrogen sources supported optimal X. campestris growth and cell yield. The addition of vitamin mixtures to complex and defined media had no significant effect on growth
or cell yield. The age of X. campestris cultures had a significant impact on cell survival after freeze drying. Following freeze drying, log phase cell survival
(44%) was significantly lower than early and late stationary phase cell survival, 62% and 68%, respectively. Cells harvested
in stationary phase, freeze dried and stored under vacuum at 4°C, showed no significant loss in viability after 6 months.
Thus, high cell concentrations of the bioherbicide X. campestris can be rapidly produced in submerged culture and stabilized as freeze-dried preparations.
Received 14 August 1998/ Accepted in revised form 8 October 1998 相似文献
11.
Seeds with ‘intermediate’ storage physiology store poorly under cold and dry conditions. We tested whether the poor shelf
life can be attributed to triacylglycerol phase changes using Cuphea carthagenensis (Jacq.) seeds. Viability remained high when seeds were stored at 25°C, but was lost quickly when seeds were stored at 5°C.
Deterioration was fastest in seeds with high (≥0.10 g g−1) and low (0.01 g g−1) water contents (g H2O g dry mass−1), and slowest in seeds containing 0.04 g g−1. A 45°C treatment before imbibition restored germination of dry seeds by melting crystallized triacylglycerols. Here, we
show that the rate of deterioration in C. carthagenensis seeds stored at 5°C correlated with the rate that triacylglycerols crystallized within the seeds. Lipid crystallization,
measured using differential scanning calorimetry, occurred at 6°C for this species and was fastest for seeds stored at 5°C
that had high and very low water contents, and slowest for seeds containing 0.04 g g−1. Germination decreased to 50% (P50) when between 16 and 38% of the triacylglycerols crystallized; complete crystallization
took from 10 to over 200 days depending on water content. Our results demonstrate interactions between water and triacylglycerols
in seeds: (1) water content affects the propensity of triacylglycerols to crystallize and (2) hydration of seed containing
crystallized triacylglycerols is lethal. We suggest that these interactions form the basis of the syndrome of damage experienced
when seeds with intermediate storage physiologies are placed in long-term storage. 相似文献
12.
《Cryobiology》2020
Flow cytometry is a valuable tool in biomedical and animal sciences. However, equipment used for such analysis presents limitations at field conditions, suggesting then preservation procedures for future analysis at laboratory conditions. In this study, freezing at low (−20 °C), ultra-low (−80 °C) and cryogenic temperatures (−196 °C, i.e. liquid nitrogen) were used as preservation procedures of fish tissue. Samples were maintained in 0.9% NaCl or lysing solution, and stored at the temperatures above for 0 (fresh control), 60, 120 and 180 days of storage. After storage, the samples were thawed and proceeded to flow cytometric analysis. Storage at low temperatures (−20 °C), both in lysing and 0.9% NaCl, exhibited poor results when analyzed after 60, 120 and 180 days, showing noisy peaks, deviation in the DNA content and absence of peaks. Ultralow (−80 °C) and cryogenic (−196 °C) temperatures, both in lysing solution and 0.9% NaCl, showed good results and high quality of histograms. Both storage procedures gave similar histograms and DNA content in comparison with control group (fresh) even after 60, 120 and 180 days of storage, exhibiting the main peak at 2C content from diploid cells and a secondary peak at 4C derived from dividing cells. In conclusion, samples may be stored for 180 days at −80 °C and −196 °C in both, 0.9% NaCl or lysing solution. As cryogenic temperatures in liquid nitrogen permits indefinite storage, this procedure should be used for long-term preservation. 相似文献
13.
We investigated the effect of carbon/nitrogen (C/N) ratio on astaxanthin synthesis in Haematococcus pluvialis during photoautotrophic induction by continuous input of both CO2–air mixture and intense light. When H. pluvialis was induced by constant irradiance induction at 200 μmol photon m−2 s−1, there was a positive correlation with astaxanthin content and C/N ratio, which was similar to the case for heterotrophic
induction. Lower C/N ratios did not retard Haematococcus encystment, but did increase culture biomass, resulting in a decrease in astaxanthin production because of light limitation.
However, induction using variable irradiance showed that reduction of astaxanthin production at low C/N ratios was successfully
overcome by simply increasing the light intensity from 200 to 300 μmol photon m−2 s−1 to overcome the light limitation. This resulted in a greatly enhanced astaxanthin synthesis in proportion to cell density
in cultures with low C/N ratios. Our results indicate that light intensity is more critical than C/N ratio in astaxanthin
production by H. pluvialis during photoautotrophic induction. 相似文献
14.
Settled zoospores of the green macroalga Enteromorpha intestinalis were subjected to several different freezing and storing
treatments at both cryogenic and non-cryogenic temperatures after which their viability was assessed using a spore germination
bioassay. Three different cooling rates were tested: slow cooling at –1°C min−1 and –0.5°C min−1 to end temperatures in the range –20°C to –40°C, and a two-step procedure whereby the spores were frozen to –30°C at a rate
of –1°C min−1 prior to immersion in liquid nitrogen at –196°C. Spore viability was also investigated using the cryoprotectants glycerol
and dimethyl suphoxide (DMSO), a reduced saline medium and various storage times. In the majority of experiments, the use
of a cryoprotectant during the freezing process significantly increased the viability of the spores, with DMSO affording slightly
greater protection than glycerol. All treatments produced high viabilities (ranging from 75.3–100.0%) after 5-min storage
at the different end temperatures. However, progressively longer storage up to 7 days generally resulted in a marked reduction
in viability. This was with the exception of spores frozen in a reduced saline medium; a medium of 75% seawater and either
5 or 10% DMSO greatly increased spore viability, with values of > 40% recorded for spores stored at –20°C for up to 5 weeks.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
Calli obtained from a shoot-tip of garlic,Allium sativum L., were encapsulated using a calcium alginate gel. Some of the encapsulated calli were cultured on a 1/2 MS medium supplemented
with 3% sucrose, 10−5 M kinetin, and 5×10−6 M NAA, whereas the remainder was stored for 40 days at 4°C. All the naked calli regenerated on the solid medium, while 95%
of the encapsulated calli regenerated, and 88% of the encapsulated calli regenerated after 40 days of storage at 4°C. The
capsule matrix delayed the germination time of the encapsulated calli, yet activated the shoot formation of the artificial
garlic seeds. The shoot length of the encapsulated garlic calli was much longer than that of the naked garlic calli. The encapsulated
garlic calli were dried in a laminar airflow cabinet and the conversion frequency of the dried artificial garlic seeds on
a 1/2 MS medium remained at 93% with a water loss of less than 50%. 相似文献
16.
The encapsulated shoot tips and nodal segments of Eclipta alba were stored at 4, 12 and 20 °C under irradiance of 1.5 gmmol m−2 s−1 and high conversion was observed in synseeds stored at 4 °C for 8 weeks. Duration of storage was extended up to 12 weeks
by decreasing sucrose concentration in the alginate matrix from 3 to 1 or 2 % and conversion frequency was 71.2–76.1 %. Synseed-derived
plantlets survived by 100 % in ex vitro conditions. RAPD analysis revealed uniform amplification profile in donor and synseed derived plantlets. 相似文献
17.
Woo-Sik Jo So-Deuk Park Seung-Chun Park Zhi-Qiang Chang Geon-Sik Seo Jae-Youl Uhm Hee-Young Jung 《Mycoscience》2009,50(1):70-73
This study was conducted to investigate the changes in characteristics of the Phellinus gilvus mushroom as influenced by drying methods after harvest. The lowest weight loss rate of P. gilvus mushroom was 75.8% with drying in the shade and 80% by dryer (60°C). The size loss rate of pileus was 19.3% of that in a
hot air dryer (60°C). The hardness of dried material context using a hot air dryer (60°C) was the lowest (20 kg/cm2), and that by a dry oven (60°C) was the highest (457 kg/m2). For ΔE value, 4.9 of context and 2.6 of tubes using drying in the shade (20°C) were found to be the lowest. The survival
rate of sarcoma 180 treated with P. gilvus dried in the sun was the lowest (51.8%), and this was considered the most effective method for antitumor activity against
sarcoma 180. 相似文献
18.
Marine, pelagic prokaryotes commonly are visualized and enumerated by epifluorescence microscopy after staining with fluorescent,
DNA-binding dyes and sample preparation and storage has a major influence on obtaining reliable estimates. However, sampling
often takes place in remote locations and the recommended continuous sample storage at −20°C until further sample evaluation
is often logistically challenging or infeasible. We investigated the effect of storage temperature on fixed and filtered seawater
samples for subsequent enumeration of total prokaryotic cells and community composition analysis by fluorescence in situ hybridization
(FISH). Prokaryotic abundance in surface seawater was not significantly different after 99 days when filters were stored either
at room temperature (RT) or at −20°C. Furthermore, there was no loss in detection rates of phylotypes by FISH from filters
stored at RT or −20°C for 28–30 days. We conclude that fixed and filtered seawater samples intended for total prokaryote counts
or for FISH may be maintained long-term at room temperature, and this should logistically facilitate diverse studies of prokaryote
ecology, biogeography, and the occurrence of human and fish/shellfish pathogens. 相似文献
19.
Irina Kovalchuk Yelena Lyudvikova Mariam Volgina Barbara M. Reed 《Plant Cell, Tissue and Organ Culture》2009,96(2):127-136
The goal of this study was to evaluate the in vitro storage of apple germplasm by screening a range of genotypes followed
by more comprehensive testing of multiple parameters on two genotypes of differing species, Malus domestica cultivar Grushovka Vernenskaya and wild Malus sieversii selection TM-6. Stored plants were rated on a 6 point scale (0 low to 5 high) for plant appearance at 3 month intervals after
storage at 4°C. Combinations of carbon source (sucrose and/or mannitol), nitrate nitrogen content (25, 50 or 100%) and plant
growth regulators (ABA, BAP, IBA) were studied in three types of containers (tissue culture bags, test tubes or jars). An
initial screen of 16 genotypes stored in tissue culture bags indicated that plantlets could be stored at 4°C for 9–14 months
without subculture on standard 3% sucrose Murashige and Skoog (1962) (MS) medium with no plant growth regulators (PGRs). In subsequent in-depth studies on the two genotypes, ANOVA indicated
highly significant interactions of medium, container and genotype. ‘Grushovka Vernenskaya’ shoots with no PGRs and 3% sucrose
remained viable (ratings of ≥1) for 21 months of storage in bags. Storage on reduced nitrogen (MS with 25% nitrogen), PGRs,
and 3% sucrose kept ‘Grushovka Vernenskaya’ shoot condition rated >2 at 21 months. Addition of 0.5 or 1 mg−1 abscisic acid (ABA) also improved plant ratings at 21 months. The longest storage for ‘Grushovka Vernenskaya’ was 33–39 months
with PGRs and 3% sucrose in either tubes or jars. Addition of abscisic acid (ABA) to the medium did not improve storage of
plantlets in jars and tubes at 15 months. TM-6 stored best in tubes on 3% sucrose with PGRs or in jars on 2% mannitol and
2% sucrose. Overall it appears that cold storage of apple shoot cultures can be successful for 21 months in tissue culture
bags with 25% MS nitrate nitrogen, 3% sucrose, and no PGRs or for 33 months in jars or tubes on MS with 3% sucrose and PGRs.
Preliminary RAPD analysis found no significant differences between plants stored for 39 months and non-stored controls. 相似文献
20.
Meana A Martinez R Cañal P Arriaga MJ Román FS Llames S Orós C Moreno A Fernandez C 《Cell and tissue banking》2006,7(3):203-206
In order to transport and cryopreserve human tissues, it is essential to have an easy-to-use recipient where tissues can be
kept in sterile conditions. Here we show the results obtained by using Macopharma’s tissue freezing bags, an aluminium-polyethylene
multilayer bag, in our tissue bank of the Centro Comunitario de Sangre y Tejidos de Asturias. Five hundred and twenty-seven
cancellous bone homografts were obtained from hospitals located 120 km around our Bank. The homografts were submitted to bacteriological
controls and sent to our bank in these bags. They were stored at −70 °C and sent in dry ice to about 50 hospitals, where the
tissue was bacteriologically controlled and grafted. Furthermore, the behaviour of these bags at −140 °C (vapour nitrogen)
or −196 °C (liquid nitrogen) was tested. Our results indicate that Macopharma aluminium-polyethylene bags are suitable for
the transporting and cryopreserving of cancellous bone homografts. These bags could also be used for keeping tissues in nitrogen
containers. 相似文献