scholarly journals Effect of suspending media on freeze-drying and preservation of vaccinia virus

1970 ◽  
Vol 68 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Masatoshi Suzuki
Keyword(s):  
Protective Effect ◽  
Vaccinia Virus ◽  
Carboxymethyl Cellulose ◽  
Freeze Drying ◽  
Chorioallantoic Membrane ◽  
Soluble Starch ◽  
Sodium Glutamate ◽  
Freeze Dried ◽  
Different Temperatures ◽  
Subsequent Storage

SummaryUnpurified and purified smallpox vaccines were prepared from calf dermal pulp, or chorioallantoic membrane (CAM) of hen eggs infected with vaccinia virus, and freeze-dried. The protective effect of various suspending media was investigated both in the course of the freeze-drying and in the period of subsequent storage of the dried product at different temperatures, including 100° C.Single media consisting of either sodium glutamate or peptone were effective in the preservation of both unpurified and purified vaccines prepared from calf dermal pulp or CAM. It was shown that there was an optimal concentration of sodium glutamate for the preservation of the vaccine preparations, especially of the purified vaccine.Combined media, consisting of soluble starch, polyvinylpyrrolidone or sodium carboxymethyl cellulose with sodium glutamate, were effective with the purified vaccine when the concentration of sodium glutamate exceeded the optimum necessary for preservation.

scholarly journals Some factors affecting preservability of freeze-dried bacteria

1961 ◽  
Vol 59 (1) ◽  
pp. 77-91 ◽  
Author(s):  
Yoji Obayashi ◽  
Sunao Ota ◽  
Shiro Arai
Keyword(s):  
Freeze Drying ◽  
Survival Rates ◽  
Heat Stability ◽  
Soluble Starch ◽  
Optimal Concentration ◽  
Sodium Glutamate ◽  
Sublimation Rate ◽  
Factors Affecting ◽  
Freeze Dried ◽  
Significant Difference

1. The use of sodium glutamate as a medium for freeze-drying Lact. bifidus significantly enhanced the stability of the dried product, especially the heat stability.2. The optimal concentration of sodium glutamate, as a drying medium, was found to depend on the bacilliary concentration; the higher the concentration of the bacilliary suspension used the higher was found to be the optimal concentration of the sodium glutamate.3. It was possible to classify various drying media according to the degree of sublimation of the product during the process of freeze-drying. Two types were observed; in the first, which included sodium glutamate and glucose, the sublimation rate diminished with the increasing concentration of the medium, whereas in the second group, which included polyvinyl pyrrolidon K 90 (PVP), soluble starch and dextran, no such diminution was observed when the concentration of the medium was increased.4. By the combination of sodium glutamate or glucose with a medium belonging to the second group sublimation was found to be promoted.5. The stabifity-conferring effect of sodium glutamate on dried Lact. bifidus was markedly enhanced when the glutamate was combined with a drying medium belonging to the second group. This effect is attributed to a desiccation-promoting property of the latter medium.6. Lact. bifidus as a freeze-dried preparation showed a somewhat better survival rate when sealed in air than when sealed in vacuo. In the case of other anaerobic organisms tested there was no significant difference in the survival rates under the two methods of storage.

scholarly journals The effect of drying temperature on the properties of gelatin from carps (Cyprinus carpio) skin

2019 ◽  
Vol 37 (No. 4) ◽  
pp. 246-251 ◽  
Author(s):  
Joanna Tkaczewska ◽  
Maciej Wielgosz ◽  
Piotr Kulawik ◽  
Marzena Zajac
Keyword(s):  
Cyprinus Carpio ◽  
Freeze Drying ◽  
Treatment Method ◽  
Thermal Hydrolysis ◽  
Gel Properties ◽  
Drying Temperature ◽  
Freeze Dried ◽  
Different Temperatures ◽  
Pre Treatment ◽  
Hydrolysis Of

The influence of drying temperature on the characteristics and gel properties of gelatine from Cyprinus carpio L. skin was studied. Gelatine was extracted from the carp skin using NaOH and ethanol pre-treatment method, extracted in water in 45°C and then dried in 4 different temperatures: 50, 70, 80°C and freeze-dried. The  electrophoresis and functional properties of gelatines were investigated. Freeze drying allowed to obtain a high gelling force, and all other methods did not give satisfactory results. The proteins in gelatines dried at higher temperatures separated by electrophoresis gave severely blurred bands. It may be explained by thermal hydrolysis of collagen fibrils. Freeze drying is the only effective method for drying this product, which can be used in industry.

scholarly journals Stability of pseudorabies virus during freeze-drying and storage: effect of suspending media

1976 ◽  
Vol 4 (1) ◽  
pp. 1-5
Author(s):  
E M Scott ◽  
W Woodside
Keyword(s):  
Freeze Drying ◽  
Pseudorabies Virus ◽  
Storage Effect ◽  
Drying Process ◽  
Sodium Glutamate ◽  
Degree Of Protection ◽  
The Stability ◽  
Subsequent Storage ◽  
And Storage ◽  
Lactalbumin Hydrolysate

The effect of suspending media on the stability of pseudorabies virus upon freeze-drying and subsequent storage was studied. A variety of media was tested, including: sodium glutamate; sucrose; lactose; lactalbumin hydrolysate; peptone; a combination of sucrose, dextran, and glutamate; and various combinations of sucrose, glutamate, and potassium phosphates. Suspending media containing glutamate, either alone or in combination with sucrose and either dextran or phosphates, afforded the greatest degree of protection during the freeze-drying process and upon storage. Some possible functions of these additives in preventing injury to the virus during freezing and drying have been suggested.

scholarly journals Viability of L. casei during fermentation in soymilk and freeze-dried soymilk; effect of cryoprotectant, rehydration and storage temperature

2006 ◽  
Vol 52 ◽  
pp. 17-24
Author(s):  
Lela Acevska ◽  
Kristina Mladenovska ◽  
Tanja Petreska Ivanovska ◽  
Maja Jurhar Pavlova ◽  
Milena Petrovska ◽  
...  
Keyword(s):  
Freeze Drying ◽  
Storage Temperature ◽  
Acid Stress ◽  
Titratable Acidity ◽  
Therapeutic Level ◽  
Freeze Dried ◽  
Different Temperatures ◽  
And Storage

Viability of L. casei during fermentation in soymilk and freeze-dried soymilk; effect of cryoprotectant, rehydration and storage temperature The aim of the work was to investigate the behaviour of L. casei and the effect of sorbitol on its viability during fermentation in soymilk drink. Values for pH, ranging from 6.82 to 3.42 in the soymilk drink without sorbitol and from 6.74 to 3.41 in the drink with sorbitol were noted during 72 h of fermentation at 25oC. The corresponding values for titratable acidity ranged from 0.071% to 0.758% and from 0.073% to 0.761%, respectively. Soymilk was found to support the growth of L. casei with improvement in viability for 0.24 log at the end of fermentation when sorbitol was added. Survival of L. casei and the effectiveness of sorbitol in improving viability during freeze-drying, subsequent rehydration and during a 5-week period of storage under different temperatures were also investigated. After freeze-drying, L. casei exhibited a survival percent of approximately 46%. Sorbitol improved the viability of L. casei by 0.51 log immediately after freeze-drying and by 1.30 log and 0.47 log during five weeks of storage at 25oC and 4oC, respectively. Further study revealed that the freeze-dried fermented soymilk rehydrated at 45oC was optimum for the recovery of L. casei with improvement in recovery for 0.68 log when sorbitol was added. A higher percent of survival was noted when the dried soymilk was stored at 4oC than at 25oC with improved viability at the end of 5 weeks storage for approximately 6 log for drinks with and without sorbitol. Fermented dried soymilk with sorbitol afforded significant tolerance of L. casei to acid stress. Generally, a stable probiotic diary product was prepared in which the concentration of L. casei remained above therapeutic level of 107 cfu/ml.

scholarly journals Effects of Carbohydrates, Prebiotics and Salts on Survival of Saccharomyces boulardii During Freeze-Drying

2018 ◽  
Vol 22 (2) ◽  
pp. 59-66
Author(s):  
Guowei Shu ◽  
Xin Yang ◽  
Zhangteng Lei ◽  
Dan Huang ◽  
Yaling ZHAI
Keyword(s):  
Survival Rate ◽  
Phosphate Buffer ◽  
Freeze Drying ◽  
Saccharomyces Boulardii ◽  
Sodium Ascorbate ◽  
Sodium Glutamate ◽  
Viable Cells ◽  
Freeze Dried ◽  
Probiotic Yeast ◽  
Addition Amount

Abstract Saccharomyces boulardii, as a probiotic yeast, had been commonly used in food, medicine and feed to treat diarrhea in humans or livestock. However, there are few researches focusing on the preparation of its freeze-drying S.boulardii powder. In this study, the effect of carbohydrates (glucose, sucrose, maltose, fructose, lactose, mannose and trehalose), prebiotics (isomalto-oligosaccharide, xylo-oligosaccharide, raffinose, stachyose, inulin, galacto-oligosaccharide and fructo-oligosaccharide) and salts (NaHCO3, MgSO4, sodium glutamate, sodium ascorbate, and phosphate buffer) on the freeze-dried survival of S. boulardii were investigated to screen the cryoprotectant by using single factor experiments. As the result, trehalose and XOS had better protective effect, the survival rate was 23.72% and 20.70% respectively, the number of viable cells reached 0.91×1010 CFU/g and 0.85×1010 CFU/g respectively; the addition amount of NaHCO3 was 0.3%, the freeze-dried survival rate reached the maximum value of 12.92%. The phosphate buffer additive amount and the bacterial sludge weight were 0.8:1, the freeze-dried survival rate reached a maximum of 14.14%, the freeze-dried survival rate of sodium glutamate, sodium ascorbate and MgSO4 groups was increasing, reaching a maximum of 20.26%, 16.47% and 6.29% when the addition amount was 2%, 10%, 0.5%.

scholarly journals Shelf-Life Evaluation and Lyophilization of PBCA-Based Polymeric Microbubbles

Pharmaceutics ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 433 ◽  
Author(s):  
Tarun Ojha ◽  
Vertika Pathak ◽  
Natascha Drude ◽  
Marek Weiler ◽  
Dirk Rommel ◽  
...  
Keyword(s):  
Shelf Life ◽  
Rhodamine B ◽  
Freeze Drying ◽  
Pharmaceutical Products ◽  
Acoustic Properties ◽  
Signal Generation ◽  
Freeze Dried ◽  
Different Temperatures ◽  
The Stability ◽  
Commercial Platform

Poly(n-butyl cyanoacrylate) microbubbles (PBCA-MB) are extensively employed for functional and molecular ultrasound (US) imaging, as well as for US-mediated drug delivery. To facilitate the use of PBCA-MB as a commercial platform for biomedical applications, it is important to systematically study and improve their stability and shelf-life. In this context, lyophilization (freeze drying) is widely used to increase shelf-life and promote product development. Here, we set out to analyze the stability of standard and rhodamine-B loaded PBCA-MB at three different temperatures (4 °C, 25 °C, and 37 °C), for a period of time of up to 20 weeks. In addition, using sucrose, glucose, polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG) as cryoprotectants, we investigated if PBCA-MB can be lyophilized without affecting their size, concentration, US signal generation properties, and dye retention. Stability assessment showed that PBCA-MB remain largely intact for three and four weeks at 4 °C and 25 °C, respectively, while they disintegrate within one to two weeks at 37 °C, thereby compromising their acoustic properties. Lyophilization analyses demonstrated that PBCA-MB can be efficiently freeze-dried with 5% sucrose and 5% PVP, without changing their size, concentration, and US signal generation properties. Experiments involving rhodamine-B loaded MB indicated that significant dye leakage from the polymeric shell takes place within two to four weeks in case of non-lyophilized PBCA-MB. Lyophilization of rhodamine-loaded PBCA-MB with sucrose and PVP showed that the presence of the dye does not affect the efficiency of freeze-drying, and that the dye is efficiently retained upon MB lyophilization. These findings contribute to the development of PBCA-MB as pharmaceutical products for preclinical and clinical applications.

Suitability of tritiated inulin for determination of glomerular filtration rate

1991 ◽  
Vol 260 (2) ◽  
pp. F283-F289 ◽  
Author(s):  
M. Shalmi ◽  
H. E. Lunau ◽  
J. S. Petersen ◽  
M. Bak ◽  
S. Christensen
Keyword(s):  
Aqueous Solution ◽  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Filtration Rate ◽  
Freeze Drying ◽  
Chromatographic Method ◽  
Freeze Dried ◽  
Chromatographic Profile ◽  
Subsequent Storage

Purity of different batches of [3H]inulin delivered from leading manufacturers was elevated with a chromatographic method (Sephadex G-25 column) that allowed simultaneous analysis of cold inulin, [3H]inulin, and [14C]inulin in the same run. Among four batches of [3H]inulin received within 5 mo, two were found relatively pure, whereas two were partly decomposed to lower-molecular-weight fragments. The chromatographic profile of pure isotopes was not significantly affected by redistribution and freeze drying, nor by subsequent storage in the freeze-dried state at -20 degrees C for up to 5 mo, nor by incubation in aqueous solution at 37 degrees C for 24 h. Three batches of [3H]inulin with different grades of decomposition (noninulin percentages 13%, 38%, and 61%, respectively) were selected for clearance experiments and infused simultaneously with cold and undecomposed [14C]inulin to conscious rats. [14C]inulin had a significantly higher clearance than cold inulin (+7.6 +/- 0.6%) and relatively pure [3H]inulin (+12.4 +/- 0.4%). Decomposed [3H]inulin isotopes progressively underestimated clearance of cold inulin to an extent related to the degree of decomposition. Thus at the end of the 5-h clearance experiment, ratios between clearance of tracer and of cold inulin were 0.92, 0.71, and 0.60 for the three 3H isotopes, respectively. This study indicates that [3H]inulin delivered from leading manufacturers may be decomposed to an extent that invalidates its use as a marker for glomerular filtration rate (GFR). It is thus necessary to check the purity routinely before use. Within the same rat, clearance of undecomposed [3H]inulin and [14C]inulin may differ by 12%, and for this reason they should not be used interchangeably as GFR markers.

scholarly journals Optimization of compatible solutes for improving survival of freeze-dried Lactobacillus delbrueckii subsp. bulgaricus using Box-Behnken design

2021 ◽  
Vol 25 (2) ◽  
pp. 301-306
Author(s):  
Guowei Shu ◽  
Bohao Li ◽  
Meng Zhang ◽  
Jie Huang ◽  
Li Chen ◽  
...  
Keyword(s):  
Survival Rate ◽  
Industrial Development ◽  
Freeze Drying ◽  
Compatible Solutes ◽  
Lactobacillus Delbrueckii ◽  
Drying Process ◽  
Sodium Glutamate ◽  
Box Behnken Design ◽  
Freeze Dried ◽  
Lactobacillus Delbrueckii Subsp

Abstract Lactobacillus delbrueckii subsp. bulgaricus is widely used in yogurt as a starter. The freeze-drying process may cause bacteria death. In the present work, the effect of three solutes (NaCl, sorbitol, and sodium glutamate) in MRS on viability of L.bulgaricus during freeze-drying was investigated. The optimal combination of adequate solutes was chosen by Box-Behnken Design. The survival rate and viable counts in freeze-dried powder, as well as the viable counts in broth, were used as responses. The results revealed that the optimum combination of solutes in MRS broth were 0.50% NaCl, 0.19% sorbitol, and 0.06% sodium glutamate. Under these optimal conditions, the survival rate was 53.2±0.14%, the viable counts in freeze-dried powder was 8.51±0.23×1010 CFU/g, and the viable counts in broth was 6.05±0.19 ×108 CFU/mL, which were increased by 17.18%, 15.94%, and 17.31%, respectively, compared to the control. This research demonstrated the possibility of viability improvement of L.bulgaricus, which may provide a feasible reference for industrial development.

scholarly journals Storage stability of freeze-dried Lactobacillus plantarum S20 starter culture as affected by various formulations of drying medium, and its fermentation characteristics in mung bean (Vigna radiata L.) slurry was studied by Sulabo et al.

Food Research ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 964-975
Author(s):  
A.S.L. Sulabo ◽  
M.E.L. Villasanta ◽  
K.G. Hermo ◽  
R.A. Lascano ◽  
L.S. Collado ◽  
...  
Keyword(s):  
Mung Bean ◽  
Freeze Drying ◽  
Starter Culture ◽  
Cell Immobilization ◽  
Starter Cultures ◽  
Fermented Foods ◽  
Viability Loss ◽  
Long Term Storage ◽  
Freeze Dried ◽  
Subsequent Storage

Development of an active starter culture is essential in the production of safe and highquality fermented foods. Freeze-drying is an effective microbial cell immobilization technology intended to produce active and stable starter cultures for long-term storage. To determine the influence of various drying medium formulations with mung bean powder and disaccharides on the viability of L. plantarum S20 during freeze-drying and subsequent storage at 6±2°C and 30±1°C, three treatments of drying medium consisting of mung bean powder without disaccharides (MBP), MBP with 5% (w/v) trehalose (MBP+T), and MBP with 5% (w/v) sucrose (MBP+T) were evaluated. Results showed that L. plantarum S20 viability after freeze-drying ranged from 9.56 to 10.03 log (CFU/g) with viability loss ranging from 0.20 to 0.51 log (CFU/g), with MBP being the least effective (p<0.05) in minimizing viability loss. Supplementing MBP with either 5% sucrose or 5% trehalose improved (p<0.05) survival of freeze-dried L. plantarum S20; and both disaccharides exhibit similar (p>0.05) cryoprotective effects on L. plantarum S20 during freeze-drying and subsequent storage. Storage at 6±2°C for 180 days resulted in significant decreases of 2.15, 2.17, and 3.27 log (CFU/g) in L. plantarum S20 population in MBP+T, MBP+S, and MBP, respectively. A more drastic decline [>6.0 Log (CFU/g)] in L. plantarum S20 population was observed in freeze-dried culture stored at 30±1°C for 60 days. Fermentation characteristics of freeze-dried L. plantarum S20 in mung bean slurry were also determined. Freeze-dried L. plantarum S20 in MBP with 5% (w/v) sucrose was able to acidify mung bean slurry from pH 6.8 to pH 3.8 after 8 hrs with maximum LAB population of 9.2 log (CFU/mL). Acidification of mung bean slurry by fresh culture (non-freeze-dried) on the other hand was relatively slower where pH dropped from 6.8 to pH 3.72 after 24 hrs. Current work suggested that lyophilized L. plantarum S20 could be used as a starter culture for mung bean-based fermentations but further research on this area is needed.

Scanning Electron Microscopy-cuticular Lesions on the Roundworm Ascaris Suum

1970 ◽  
Vol 28 ◽  
pp. 114-115
Author(s):  
P. A. Madden ◽  
W. R. Anderson
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Freeze Drying ◽  
Room Temperature ◽  
Secondary Electron ◽  
Distilled Water ◽  
Freeze Dried ◽  
Silver Paint ◽  
To Come ◽  
Scanning Electron

The intestinal roundworm of swine is pinkish in color and about the diameter of a lead pencil. Adult worms, taken from parasitized swine, frequently were observed with macroscopic lesions on their cuticule. Those possessing such lesions were rinsed in distilled water, and cylindrical segments of the affected areas were removed. Some of the segments were fixed in buffered formalin before freeze-drying; others were freeze-dried immediately. Initially, specimens were quenched in liquid freon followed by immersion in liquid nitrogen. They were then placed in ampuoles in a freezer at −45C and sublimated by vacuum until dry. After the specimens appeared dry, the freezer was allowed to come to room temperature slowly while the vacuum was maintained. The dried specimens were attached to metal pegs with conductive silver paint and placed in a vacuum evaporator on a rotating tilting stage. They were then coated by evaporating an alloy of 20% palladium and 80% gold to a thickness of approximately 300 A°. The specimens were examined by secondary electron emmission in a scanning electron microscope.

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