Expression of clpL1 and clpL2 genes in Lactobacillus rhamnosus VTT E-97800 after exposure to acid and heat stress treatments or to freeze-drying

2010 ◽  
Vol 1 (3) ◽  
pp. 253-257 ◽  
Author(s):  
C. Simões ◽  
H. Alakomi ◽  
J. Maukonen ◽  
M. Saarela
Keyword(s):  
Freeze Drying ◽  
Lactobacillus Rhamnosus ◽  
Rna Isolation ◽  
Laboratory Scale ◽  
Quality Analysis ◽  
Stress Genes ◽  
Freeze Dried ◽  
Related Stress ◽  
Harsh Conditions

The aim of the study was to evaluate the potential of utilising the information on expression levels of selected stress genes in assessing the quality of probiotic products. For this purpose RT-qPCR methods were developed to study the expression of clpL1 and clpL2 stress genes in Lactobacillus rhamnosus VTT E-97800 (E800) cells after exposure to processing-related stress conditions or to freeze-drying. Heat treatments in laboratory scale were performed with E800 cells incubated at 47 °C or 50 °C for 60 min. Acid treatments were performed both at laboratory and fermenter scale. At laboratory scale E800 cells were inoculated into General Edible Medium (GEM) adjusted to pH 4.0 and pH 3.5 and incubated at 37 °C for 180 min, whereas fermenter-grown cells were exposed to pH 4.0 for 60 min at the end of the fermentation. RNA from fresh cells and freeze-dried powders was reverse transcribed after isolation, quantification and standardisation. clpL1 and clpL2 transcripts were analysed by RT-qPCR with SYBR Green I. clpL1 was induced in L. rhamnosus E800 cells exposed to 50 °C and to a much lesser extent to 47 °C. No induction was observed for clpL2 in E800 cells during either acid or heat treatment, in any of the conditions applied. RNA isolation from freeze-dried powders was unsuccessful although several attempts were made with high quality products. In conclusion, our results suggest that developing quality indicators for probiotic products based on differences in the expression of stress genes is a challenging task for several reasons: at least with some genes (like in the present study with clpL) quite harsh conditions are needed to detect differences in the gene expression; mRNA isolation from freeze-dried powders was unsuccessful which hampers the quality analysis of large proportion of probiotic products; and furthermore RT-qPCR proved to be a too laborious procedure for routine use.

scholarly journals The Quality of Red Bell Pepper Subjected to Freeze-Drying Preceded by Traditional and Novel Pretreatment

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 226
Author(s):  
Katarzyna Rybak ◽  
Artur Wiktor ◽  
Dorota Witrowa-Rajchert ◽  
Oleksii Parniakov ◽  
Małgorzata Nowacka
Keyword(s):  
Freeze Drying ◽  
Bell Pepper ◽  
Total Phenolic ◽  
Thermal Methods ◽  
Drying Time ◽  
Freeze Dried ◽  
Dehydration Processes ◽  
Vacuum Freezing ◽  
Better Than

It has been demonstrated previously in the literature that utilization of PEF or a combination of a pulsed electric field (PEF) and ultrasounds (US) can facilitate dehydration processes and improve the quality of dried products even better than the application of thermal methods such as blanching. The aim of the study was to evaluate the quality of red bell pepper subjected to freeze-drying preceded by blanching or PEF or US treatment applied in a single and combined mode. Furthermore, the freeze-drying was preceded by shock freezing or vacuum freezing performed inside the freeze-dryer as a result of pressure drop during the first stage of freeze-drying. All of the analyzed technological variants enhanced the drying kinetics when compared to the intact material. Freeze-dried bell pepper subjected to non-thermal pretreatment exhibited higher vitamin C, total phenolic and carotenoids content than blanched material despite the fact that blanching reduced drying time the most compared to all other analyzed methods.

scholarly journals Effect of Supplementation of Dried Bioflocs Produced by Freeze-Drying and Oven-Drying Methods on Water Quality, Growth Performance and Proximate Composition of Red Hybrid Tilapia

2022 ◽  
Vol 10 (1) ◽  
pp. 61
Author(s):  
Tarq Binalshikh-Abubkr ◽  
Marlia Mohd Hanafiah
Keyword(s):  
Water Quality ◽  
Body Composition ◽  
Growth Performance ◽  
Freeze Drying ◽  
Energy Levels ◽  
Fish Growth ◽  
Drying Methods ◽  
Oven Drying ◽  
Freeze Dried

Supplementation of dried bioflocs for red hybrid tilapia (Oreochromis sp.) was examined during 57 days of feeding trials. Five experimental treatments; T1 (the control; without bioflocs), T2 (4% freeze-dried bioflocs), T3 (16% freeze-dried bioflocs), T4 (4% oven-dried bioflocs), and T5 (16% oven-dried bioflocs) were prepared to examine the water quality, growth performance and body composition of red hybrid tilapia. T2 and T4 treatments resulted in a higher growth rate and survival similar to the control, while T3 and T5 treatments showed the lowest values of growth performance among all treatments. T1 treatment showed the best quality of culture water followed by T2 and T4 treatments, while T3 treatment resulted in poor water quality followed by T5 treatment. Based on these results, the ratios of bioflocs (4% and 16%) had more effect on fish growth and water quality than the drying methods (freeze-drying and oven-drying). The ratio of 4% freeze-dried or oven-dried bioflocs provided higher growth rates and better water quality parameters similar to the control, while the ratio of 16% showed the worst growth performance and water quality in the present study. In addition, body compositions of tilapia fed 4% dried bioflocs showed better nutritional value than tilapia fed 16% dried bioflocs. Protein and energy levels showed an increasing trend with decreasing supplement levels of bioflocs. Moisture content was significantly higher when supplementation of 16% bioflocs was used. Overall, supplementation of 4% freeze-dried or oven-dried bioflocs can be successively included in red hybrid tilapia diets without any effects on growth or body composition and can result in a good quality of culture water for red hybrid tilapia.

scholarly journals Effect of lacto-fermentation and freeze-drying on the quality of beetroot evaluated using machine vision and sensory analysis

2021 ◽  
Author(s):  
Ewa Ropelewska ◽  
Anna Wrzodak ◽  
Kadir Sabanci ◽  
Muhammet Fatih Aslan
Keyword(s):  
Freeze Drying ◽  
Sensory Quality ◽  
Bitter Taste ◽  
Sensory Attributes ◽  
Discrimination Accuracy ◽  
Flatbed Scanner ◽  
Color Channel ◽  
Texture Parameters ◽  
Freeze Dried

AbstractThis study was aimed at evaluating the effect of freeze-drying and lacto-fermentation on the texture parameters of images and sensory attributes of beetroots. The samples were imaged using a flatbed scanner, and textures from images converted to color channels L, a, b, R, G, B, X, Y, Z were computed. The discrimination of raw and processed beetroots was performed using models based on textures selected for each color channel. The sensory quality of processed samples was determined using the attributes related to smell, color, texture and taste. The highest discrimination accuracy of 97.25% was obtained for the model built for color channel b. The accuracies for other channels were equal to 96.25% for channel a, 95.25% for channel R, 95% for channel Y, 94.75% for channel B, 94.5% for channel X, 94% for channel L, 92.5% for channel G, 88.25% for channel Z. In the case of some models, the raw and lacto-fermented beetroots were discriminated with 100% correctness. The freeze-dried and freeze-dried lacto-fermented samples were also the most similar in terms of sensory attributes, such as off-odor, attractiveness color, beetroot color, crunchiness, hardness, bitter taste, overall quality. The results indicated that the image parameters and sensory attributes may be related.

Effect of Freeze-Drying and Cooking on Shrimp Quality

1970 ◽  
Vol 53 (5) ◽  
pp. 899-902 ◽  
Author(s):  
Barbara R Moorhouse ◽  
Harold Salwin
Keyword(s):  
Freeze Drying ◽  
Starting Material ◽  
White Shrimp ◽  
Chemical Analyses ◽  
Decomposition Products ◽  
Organoleptic Quality ◽  
Freeze Dried ◽  
Plate Counts ◽  
Crushed Ice

Abstract Approximately 500 pounds of white shrimp were stored in crushed ice until they decomposed. Portions were withdrawn at intervals and processed. Based on judgments of odor, shrimp that reached a stage of incipient decomposition before processing were rated as passable after they were freeze-dried or cooked. The organoleptic quality of samples that reached a stage of advanced decomposition was also improved by processing, but not to the extent of their being classified as passable. Aerobic plate counts increased during storage but they were reduced significantly by freezedrying or cooking. Although there were changes in composition during storage, the classical chemical tests used were of limited value for assessing the degree of decomposition. Also, many volatile decomposition products were lost during processing. Computing the results of chemical analyses on a moisturefree basis offered distinct advantages. Inasmuch as organoleptic, bacteriological, and chemical tests on the finished products failed to reveal the decomposed condition of the starting material, there is need for additional investigation of methods for that purpose.

scholarly journals THE DIFFERENCE OF TENSILE STRENGTH AND YIELD FIBRINOGEN ON FIBRIN GLUE PREPARATIVE BY CRYOPRESIPITATE WITH AND WITHOUT FREEZE DRYING METHODS

2019 ◽  
Vol 25 (3) ◽  
pp. 349
Author(s):  
Brilliant Margalin ◽  
S. P. Edijanto ◽  
Paulus B. Notopuro
Keyword(s):  
Tensile Strength ◽  
Fibrin Glue ◽  
Freeze Drying ◽  
Drying Methods ◽  
Drying Process ◽  
Freeze Dried ◽  
Significant Difference ◽  
Fibrinogen Content

Fibrin glue is a useful biological product to stop bleeding, adhesive tissue and accelerate wound healing. Preparation of Fibrin Glue requires fibrinogen and thrombin components. The routine cryoprecipitation method performed at the Blood Bank can be used to improve the quality of the fibrinogen component. The Freeze Drying process can increase the retention time of plasma products at room temperature. Yield Fibrinogen and Tensile Strength is a quantitative and qualitative parameter of preparation quality of fibrin glue. This study focused on finding differences between Tensile Strength and Yield Fibrinogen on fibrin glue preparative by cryoprecipitate with and without freeze drying methods.This study is in vitro laboratory experiments design by comparing the Yield Fibrinogen and Tensile Strength of fibrin glue preparation from cryoprecipitic plasma with and without freeze dried process. The results were analyzed comparatively using paired T test.The plasma fibrinogen content of the sample was 237.66 ± 67.10 mg / dL. The fibrinogen content of the cryoprecipitate component without freeze drying process was 327.74 ± 103.42 mg / dL with a yield fibrinogen of 1.38 ± 0.25. The fibrinogen content of the cryoprecipitate component with freeze drying process was 251.20 ± 103.91 mg / dL with yield fibrinogen 1.04 ± 0.25. Tensile strength of fibrin glue from cryoprecipitate without freeze drying process was found to average 0.52 ± 0.18. Tensile strength of fibrin glue from cryoprecipitate with freeze drying process was found to average 0.33 ± 0.12. There was a significant difference between yield fibrinogen and tensile strength of fibrin glue preparation of cryoprecipitation method with and without freeze dried process.There is a significant difference on yields fibrinogen and tensile strength in the preparation of fibrin glue by the freeze drying process which is probably due to changes in the structure and function of fibrinogen proteins.

scholarly journals Lyophilization biologicals products. Equipment. Technology. Validation.

2021 ◽  
Author(s):  
E.S. Serbis ◽  
I.N., Matveeva ◽  
V. I. Eremets
Keyword(s):  
Industrial Production ◽  
Freeze Drying ◽  
Heating Temperature ◽  
Liquid Product ◽  
Integrated Approach ◽  
Maximum Temperature ◽  
Drying Process ◽  
Entire Volume ◽  
Freeze Dried

Тhe aseptic process of industrial production of sterile lyophilized biological products is completed by one of the critical stages of the technological process, the freeze-drying. GOST R ISO 13408-3-2011 defines the term lyophilization as a synonym for the sublimation. Sublimation - the physical process on which the freeze-drying method is based. This paper discusses the issues of freeze drying that engineers and biologists, production technologist, designers of dry preparations, and quality specialists face with. Freeze-drying consists of three stages: freezing, freeze-drying and drying. Each stage has its own critical points, input and output parameters. The task of the developer of freeze-drying technology is to determine the need for each parameter and the sufficiency of their quantity. Equipment, technology and regulatory documents are considered as interdependent elements that make up freeze drying as a system. An integrated approach to the freeze-drying process includes the development of modes, equipment control, and internal documentation. The key parameters of the process are the qualitative and quantitative characteristics (reference values, measurement procedures, acceptable range of values) of the semi-finished liquid product and the finished freeze-dried product. Characteristics of the semi-finished liquid product are the temperature of complete crystallization; upper and lower eutectic temperatures; maximum permissible heating temperature (thermo-lability); density; specific (biological) activity. Freeze-drying process characteristics are: at the freezing stage - reaching the temperature of complete crystallization in the entire volume of the material received for drying; at the sublimation stage - maintaining the temperature in the dried material in the range between the lower and upper eutectic temperatures (without going beyond the upper); at the drying stage - reaching the maximum temperature in the material. The duration of each stage depends on the vial in which the dried material is packed, the volume of packaging, and the features of heat, mass, and energy exchange in the sublimation plant. Standard operating procedures (SOPs) should be designed with these features in mind. For example, for different packages (2ml or 10ml) in vials of the same volume, or for the same packaging in vials of different volumes, for example, 2ml in vial of 10-ml or 20-ml, separate SOPs are required in each case. In the current practice of industrial production, the quality of the lyophilized product is evaluated by humidity (GOST 24061-2012). In our work, to assess the quality of the process, we measured the decrease in the mass of liquid material during drying. We recommend measure both indicators, since they complement each other.

scholarly journals Topical Probiotics for Women’s Urogenital Health: Selection of an Oil-based Carrier

2021 ◽  
Vol 06 (04) ◽  
pp. 1-1
Author(s):  
Scarlett Puebla-Barragan ◽  
◽  
Britney Lamb ◽  
Serenah Jafelice ◽  
Gregor Reid ◽  
...  
Keyword(s):  
Lactobacillus Reuteri ◽  
Lactobacillus Rhamnosus ◽  
Coconut Oil ◽  
Petroleum Jelly ◽  
Vaginal Microbiome ◽  
Topical Product ◽  
Freeze Dried ◽  
Probiotic Strains ◽  
Selection Of

Vaginal care products are widely used by women to relieve discomfort such as pain, itching and malodour, all of which are commonly caused by conditions resulting from microbiota dysbiosis. Previous studies showed that probiotic strains Lacticaseibacillus (formerly Lactobacillus) rhamnosus GR-1 (LGR-1) and Limosilactobacillus (formerly Lactobacillus) reuteri RC-14 (LRC-14), can aid in restoring homeostasis in the vaginal microbiome when taken orally. A topical product containing these strains could be of value for reducing malodour and improving quality of life. However, the formulation of such a product is a challenge, given that its ingredients must maintain shelf-life viability by excluding moisture. Here, we tested petroleum jelly, mineral oil, coconut oil, and olive oil for how well they maintained the viability of freeze-dried probiotic strains over a six-month timeframe. None of the oils caused excessive loss of bacterial viability, with petroleum jelly and coconut oil showing the most promise. Based on existing knowledge of these oils on the female genitalia, coconut oil and petroleum jelly could be suitable probiotic carriers for clinical testing.

scholarly journals α-amylase activity in freeze-dried and spray-dried honey

2020 ◽  
Author(s):  
Anete Keke ◽  
◽  
Ingmars Cinkmanis ◽  
Keyword(s):  
High Performance ◽  
Freeze Drying ◽  
Negative Impact ◽  
Amylase Activity ◽  
Drying Methods ◽  
Sugar Solution ◽  
Powder Concentration ◽  
Freeze Dried ◽  
Spray Dried

Honey is a naturally supersaturated sugar solution, which tends to crystallize. The crystallization of honey can lead to unwanted fermentation that can have a negative impact to honey quality. The production of honey powder could be an alternative method to prevent honey from fermentation. Honey powder could be used as alternative substitute to liquid honey that would allow to use this product more widely in the food industry. α-amylase activity is one of the most important parameters to evaluate the quality of honey. The aim of this study was to investigate the effect of freeze-drying and spray-drying on honey α-amylase activity. Detection of α-amylase activity was carried out by spectrophotometric method. High-performance liquid chromatography was used to determine the content of hydroxymethylfurfural in the powders. The obtained results showed that both drying methods had a negative impact to the enzyme activity in the samples. The lowest activity of α-amylase (8.3 DN) was measured in the spray-dried honey powder. Concentration of hydroxymethylfurfural (HMF) in the powders did not exceed required concentration 40 mg kg-1.

scholarly journals Application of Ultrasound and Curing Agent during Osmotic Dehydration to Improve the Quality Properties of Freeze-Dried Yellow Peach (Amygdalus persica) Slices

Agriculture ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1069
Author(s):  
Yuanming Chu ◽  
Saichao Wei ◽  
Zhaoyang Ding ◽  
Jun Mei ◽  
Jing Xie
Keyword(s):  
Freeze Drying ◽  
Osmotic Dehydration ◽  
Average Pore Size ◽  
Nutrient Loss ◽  
Ultrasonic Power ◽  
Curing Agent ◽  
Average Pore ◽  
Quality Properties ◽  
Freeze Dried

This study aimed to improve the quality of freeze-dried yellow peaches (Amygdalus persica). Yellow peaches were pretreated with osmotic dehydration for 15 min prior to vacuum-freeze drying and supplemented with different ultrasonic power levels (180 W, 240 W, 300 W) and a curing agent (calcium lactobionate, CaLa) to investigate the effects on the quality of freeze-dried yellow peach slices. After vacuum freeze-drying the yellow peach slices for 48 h, their moisture, color, texture, microstructure, total phenol (TP) content and oligomeric proantho-cyanidin (OPC) content were determined. It was found that the auxiliary ultrasonic power with various levels, especially powered at 240 W, produced very favorable effects on the quality characteristics of freeze-dried yellow peaches. The average pore size of USOD-240 W samples was reduced by 57.07% compared with that of the FD samples. In terms of nutrient maintenance, USOD-240 W can also prevent nutrient loss to the greatest extent. The TP content (5.40 mg/g) and OPC content (14.42 mg/g) were always highest in each pretreatment. The addition of CaLa can further improve the quality of yellow peach slices. Overall, the application of ultrasound and CaLa to improve the quality of freeze-dried yellow peach slices along with osmotic dehydration before freeze-drying is a method worth considering.

scholarly journals Lyophilization of Liposomal Formulations: Still Necessary, Still Challenging

Pharmaceutics ◽  
2018 ◽  
Vol 10 (3) ◽  
pp. 139 ◽  
Author(s):  
Silvia Franzé ◽  
Francesca Selmin ◽  
Elena Samaritani ◽  
Paola Minghetti ◽  
Francesco Cilurzo
Keyword(s):  
Freeze Drying ◽  
Process Conditions ◽  
Solvent Mixtures ◽  
Protective Mechanisms ◽  
Routes Of Administration ◽  
Solid Dosage ◽  
Liposomal Formulations ◽  
Freeze Dried ◽  
Drug Leakage

Nowadays, the freeze-drying of liposome dispersions is still necessary to provide a solid dosage form intended for different routes of administration (i.e., parenteral, oral, nasal and/or pulmonary). However, after decades of studies the optimization of process conditions remains still challenging since the freezing and the dehydration destabilize the vesicle organization with the concomitant drug leakage. Starting from the thermal properties of phospholipids, this work reviews the main formulation and process parameters which can guarantee a product with suitable characteristics and increase the efficiency of the manufacturing process. In particular, an overview of the cryo- and/or lyo-protective mechanisms of several excipients and the possible use of co-solvent mixtures is provided. Attention is also focused on the imaging methods recently proposed to characterize the appearance of freeze-dried products and liposome dispersions upon reconstitution. The combination of such data would allow a better knowledge of the factors causing inter-vials variability in the attempt to improve the quality of the final medicinal product.

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