scholarly journals Study and optimization of freeze-drying cycles of a model probiotic strain

2018 ◽  
Author(s):  
Pierre Verlhac ◽  
Séverine Vessot-Crastes ◽  
Ghania Degobert ◽  
Claudia Cogné ◽  
Julien Andrieu ◽  
...  
Keyword(s):  
Experimental Study ◽  
Survival Rate ◽  
Lactobacillus Casei ◽  
Freeze Drying ◽  
Survival Rates ◽  
Probiotic Strain ◽  
Porous Matrix ◽  
Drying Process ◽  
The Matrix ◽  
The Impact

This work is based on the experimental study of the freeze-drying process to understand the impact of numerous factors on the survival rates of a model probiotic strain of Lactobacillus casei type. With the aim to find out if cell density in the matrix and survival rates are linked, we have studied the location of the cells after freeze drying inside a porous  matrix composed of a lactose basis with a polymer, the polyvinylpyrrolidone (PVP) in various amounts. The best survival rate were obtained at slow freezing rate for a formulation containing 5% (m/V) of lactose and 5% (m/V) of PVP. Keywords: Freeze-Drying; Freezing; Probiotics; L. Casei ATCC 393 

scholarly journals Studies on the Catalytic Properties of Crude Freeze-Dried Preparations of Yarrowia lipolytica Extracellular Lipases for Geranyl Ester Derivative Synthesis

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 839
Author(s):  
Karina Jasińska ◽  
Bartłomiej Zieniuk ◽  
Dorota Nowak ◽  
Agata Fabiszewska
Keyword(s):  
Freeze Drying ◽  
Antioxidant Properties ◽  
Antibacterial Properties ◽  
Synthetic Activity ◽  
Drying Process ◽  
Enzyme Preparations ◽  
Ester Derivative ◽  
Freeze Dried ◽  
The Impact ◽  
Geranyl Ester

The study aimed to evaluate the impact of selected factors of the freeze-drying process on the hydrolytic and synthetic activity of the extracellular lipases of Y. lipolytica KKP 379 and to attempt the use of the crude enzyme preparation as a biocatalyst in the synthesis of geranyl 4-hydroxyphenylpropanoate. Antioxidant and antibacterial properties of the geranyl ester derivative were also investigated in order to evaluate their usefulness as a novel food additive. The studies confirmed that freeze-drying was an effective method of dehydrating yeast supernatant and allowed for obtaining lyophilizates with low water activity from 0.055 to 0.160. The type and concentration of the additive (2–6% whey protein hydrolyzate, 0.5% and 1% ammonium sulphate) had a significant effect on the hydrolytic activity of enzyme preparations, while the selected variants of drying temperature during the freeze-drying process were not significant (10 °C and 50 °C). Low yield of geranyl 4-hydroxyphenylopropionate was shown when the lyophilized supernatant was used (5.3%), but the yield of ester synthesis increased when the freeze-dried Y. lipolytica yeast biomass was applied (47.9%). The study confirmed the antioxidant properties of the synthesized ester by the DPPH• and CUPRAC methods, as well as higher antibacterial activity against tested bacteria than its precursor with 0.125 mM MIC (minimal inhibitory concentration) against L. monocytogenes.

Effect of different encapsulating agent combinations on viability of Lactobacillus casei Shirota during storage, in simulated gastrointestinal conditions and dairy dessert

2019 ◽  
Vol 25 (7) ◽  
pp. 608-617 ◽  
Author(s):  
Osman Gul ◽  
Ilyas Atalar ◽  
Latife Betul Gul
Keyword(s):  
Lactobacillus Casei ◽  
Freeze Drying ◽  
Survival Rates ◽  
Skim Milk ◽  
Gum Arabic ◽  
Storage Conditions ◽  
Ternary Mixtures ◽  
Gastrointestinal Conditions ◽  
Lactobacillus Casei Shirota ◽  
Free Cells

In this study, the effects of various matrices consisting of maltodextrin and reconstitute skim milk and their binary and ternary mixtures with gum Arabic in the microencapsulation of Lactobacillus casei Shirota by freeze-drying technique were assessed. Microcapsules produced with reconstitute skim milk showed high viability (>99%) after freeze drying. While the free cells were completely inactivated after exposure to simulated gastrointestinal conditions, the survival rates of microencapsulated L. casei Shirota were found high for all microcapsules except for maltodextrin and maltodextrin:gum Arabic formulas. The viability of microencapsulated L. casei Shirota during storage at refrigerate and room temperatures decreased between 0.39 and 2.43 log cycles and microcapsules produced with reconstitute skim milk:gum Arabic was found more durable at the both storage conditions. Reduction in the number of free cells was higher than encapsulated L. casei Shirota numbers during production of dessert, however the viability of encapsulated L. casei Shirota was found stable for 14 days of storage and consequently desserts containing encapsulated L. casei Shirota (except maltodextrin) showed stable pH values. This study revealed that combination of reconstitute skim milk:gum Arabic was an effective wall matrix for microencapsulation of L. casei Shirota by freeze drying and also very resistant against gastrointestinal fluids and storage conditions in view of protection of L. casei Shirota.

scholarly journals Effect of Drying Process, Encapsulation, and Storage on the Survival Rates and Gastrointestinal Resistance of L. salivarius spp. salivarius Included into a Fruit Matrix

2020 ◽  
Vol 8 (5) ◽  
pp. 654
Author(s):  
Ester Betoret ◽  
Noelia Betoret ◽  
Laura Calabuig-Jiménez ◽  
Cristina Barrera ◽  
Marco Dalla Rosa
Keyword(s):  
Survival Rate ◽  
Physicochemical Properties ◽  
Freeze Drying ◽  
Molecular Mechanisms ◽  
Survival Rates ◽  
In Vitro Digestion ◽  
Hot Air ◽  
Freeze Dried ◽  
And Storage

In a new probiotic food, besides adequate physicochemical properties, it is necessary to ensure a minimum probiotic content after processing, storage, and throughout gastrointestinal (GI) digestion. The aim of this work was to study the effect of hot air drying/freeze drying processes, encapsulation, and storage on the probiotic survival and in vitro digestion resistance of Lactobacillus salivarius spp. salivarius included into an apple matrix. The physicochemical properties of the food products developed were also evaluated. Although freeze drying processing provided samples with better texture and color, the probiotic content and its resistance to gastrointestinal digestion and storage were higher in hot air dried samples. Non-encapsulated microorganisms in hot air dried apples showed a 79.7% of survival rate versus 40% of the other samples after 28 days of storage. The resistance of encapsulated microorganisms to in vitro digestion was significantly higher (p ≤ 0.05) in hot air dried samples, showing survival rates of 50–89% at the last stage of digestion depending on storage time. In freeze dried samples, encapsulated microorganisms showed a survival rate of 16–47% at the end of digestion. The different characteristics of the food matrix after both processes had a significant effect on the probiotic survival after the GI digestion. Documented physiological and molecular mechanisms involved in the stress response of probiotic cells would explain these results.

scholarly journals Effect of the Freeze-Drying Process on the Physicochemical and Microbiological Properties of Mexican Kefir Grains

Processes ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 127 ◽  
Author(s):  
Alicia Conde-Islas ◽  
Maribel Jiménez-Fernández ◽  
Denis Cantú-Lozano ◽  
Galo Urrea-García ◽  
Guadalupe Luna-Solano
Keyword(s):  
Moisture Content ◽  
Water Activity ◽  
Freeze Drying ◽  
Survival Rates ◽  
Freezing Temperature ◽  
Freezing Time ◽  
Residual Moisture Content ◽  
Drying Process ◽  
Residual Moisture ◽  
Kefir Grains

The purpose of this study was to investigate how the properties of Mexican kefir grains (MKG) are affected by the operating parameters used in the freeze-drying process. The factors investigated were the freezing time (3–9 h), freezing temperature (−20 to −80 °C), pressure (0.2–0.8 mbar), and lyophilization time (5–20 h). The maximum range of change and one-way analysis of variance showed that lyophilization time and freezing time significant affects (p < 0.05) the response variables, residual moisture content and water activity, and pressure had a significant effect on the color difference and survival rate of probiotic microorganisms. The best drying conditions were a freezing time of 3 h, a freezing temperature of −20 °C, a pressure of 0.6 mbar, and a lyophilization time of 15 h. Under these conditions, we obtained a product with residual moisture content below 6%, water activity below 0.2, and survival rates above 8.5 log cfu per gram of lactic acid bacteria and above 8.6 log for yeast.

Impact of obesity upon the survival of cholangiocarcinoma patients.

2019 ◽  
Vol 37 (4_suppl) ◽  
pp. 288-288
Author(s):  
Phani Keerthi Surapaneni ◽  
Zhuo Li ◽  
Lalitha Padmanabha Vemireddy ◽  
Pashtoon Murtaza Kasi ◽  
Jason Scott Starr ◽  
...  
Keyword(s):  
Overall Survival ◽  
Survival Rate ◽  
Survival Rates ◽  
Tumor Location ◽  
Normal Weight ◽  
Categorical Variables ◽  
Overall Survival Rate ◽  
Exact Test ◽  
Significant Difference ◽  
The Impact

288 Background: Obesity is a risk factor for developing cholangiocarcinoma (CCA). However, the effect of obesity on survival of CCA is unclear. The primary aim of this study was to analyze the impact of obesity upon overall survival of CCA patients. Secondary aims were to analyze impact of obesity upon other disease characteristics such as tumor site, stage, age, sex, BMI and Ca 19-9. Methods: A total of 411 unique pts diagnosed with CCA at Mayo Clinic Florida between 2000 and 2018 were retrieved from our collective SDMS database. Variables evaluated included:demographics, Body Mass Index (BMI), AJCC stage, tumor location and Ca 19-9.A total of 185 pts had all data available pertaining to these variables. We further restricted the analysis to pts with intrahepatic CCA classified BMI as per CDC criteria normal (18.5-25kg/m2), overweight (25-29.9kg/m2) and obese (≥30 kg/m2), thus leaving a total of 152 pts. Continuous and categorical variables were compared across BMI groups using Chi-squared or Fisher’s exact test. Overall survival rates after diagnosis at 1, 2 and 3 years were estimated using Kaplan-Meier method. Results: Among 152 pts included in the study, 28% were normal weight, 40% were overweight and 32% were obese. The overall survival rate at 1, 2 and 3 years for normal weight pts with all stages combined was 54.1%, 35%, and 30.7%, respectively. The overall survival rate at 1, 2 and 3 years for overweight pts with all stages combined was 59.7 %, 32.6%, and 25.4%, respectively. The overall survival rate at 1, 2 and 3 years for obese pts with all stages combined was 63.9%, 37.6%, and 26.7%, respectively(p = 0.8766). Multivariate analysis demonstrated is no significant difference in overall survival for obese pts compared to normal or overweight pts.(Table to be shown) However it showed, gender and Ca19-9 were statistically significant predictors of overall survival, with males and pts with Ca19-9≥100 doing worse (HR1.65 (CI = 1.05, 2.61, p = 0.031) and HR 2.31 (CI = 1.49, 3.59, p = < 0.01), respectively). Conclusions: BMI did not make a significant impact on the overall survival, though there may be a trend toward worse OS for ptswith higher BMI. A larger, stage focused evaluation is warranted for further exploration of this trend.

scholarly journals Survival Analysis of Chronic Kidney Disease Patients with Hemodialysis in West Java. Indonesia, Year 2007 - 2018

2020 ◽  
Vol 52 (3) ◽  
pp. 172-179
Author(s):  
Afiatin ◽  
Dwi Agustian ◽  
Kurnia Wahyudi ◽  
Pandu Riono ◽  
Rully M. A. Roesli
Keyword(s):  
Chronic Kidney Disease ◽  
Survival Analysis ◽  
Survival Rate ◽  
Kidney Disease ◽  
Demographic Data ◽  
Survival Rates ◽  
Treatment Quality ◽  
West Java ◽  
Dialysis Treatment ◽  
The Impact

The prevalence of chronic kidney disease on dialysis or CKD5D is increasing with a significant impact on disease burden in many countries. Patients are usually listed in the national renal registries, which report demographic data, incidence, prevalence, and outcome. The survival rate is an important outcome measure to characterize the impact of treatment in the CKD5 patient population in the national and international renal registries. Indonesian Society of Nephrology (InaSN) has the Indonesian Renal Registry program to collect data that was endorsed to monitor dialysis treatment quality in Indonesia. IRR releases an annual report, but there is no survival analysis yet. This study aimed to discover the five-year survival rate of CKD5D patients in West Java between 2007–2018 and its factor based on the IRR database. A retrospective cohort study was performed by gaining all patients' data from the IRR database, then data on all of the patients from West Java province who completed a 5-year follow-up on December 31, 2018. Kaplan-Meier analysis and Cox proportional hazard's model were used to analyze the risk factors. There were 3,199 data included in this study. In total, the 1, 2, 3, 4, and 5 year survival rates are 82%, 70%, 62%, 58%, and 55 %, respectively. Patients whose age is above 55 years and with unknown underlying kidney disease have a worse survival rate with a hazard ratio of 1.28 and 1.50, respectively. Further exploration of IRR data will provide better information on dialysis treatment in Indonesia.

Systemic ventricle morphology impact on ten-year survival after Fontan surgery

2018 ◽  
Vol 26 (9) ◽  
pp. 677-684 ◽  
Author(s):  
Mira Fauziah ◽  
Oktavia Lilyasari ◽  
Lies Dina Liastuti ◽  
Budi Rahmat
Keyword(s):  
Survival Rate ◽  
Fontan Procedure ◽  
Fontan Operation ◽  
Survival Rates ◽  
Univentricular Heart ◽  
Thromboembolic Events ◽  
Term Survival ◽  
Systemic Ventricle ◽  
The Impact

Background The Fontan procedure has been applied in many patients with single-ventricle physiology, with quite low mortality rates all over the world, and a 8.6%–9.1% rate in Indonesia. Structural and characteristic differences in the morphologically left and right ventricles influence the role of the systemic ventricle in the functionally univentricular heart and impact on postoperative outcomes. Mid- and long-term survival based on systemic ventricle morphology remains controversial. This study aimed to investigate the impact of systemic ventricle morphology on ten-year survival after the Fontan procedure. Methods The 162 patients who underwent a Fontan operation at our institution between 2008 and February 2018 and survived to discharge were reviewed and followed up until March 2018. Data were extracted from the registry and pediatric surgical conferences, medical records, surgery reports, echocardiography and catheterization reports, and follow-up to the end of the study period. Median follow-up was 26.5 months (range 10.75–54 months). Results The patients were divided into 2 groups based on systemic ventricle morphology. Seventy-four patients were included in the left morphology group and 88 in the right morphology group. There was no difference in 10-year survival rates between the two type of systemic ventricle morphology. Postoperative thromboembolic events influenced the 10-year survival rate after the Fontan procedure (hazard ratio 4.84, 95% confidence interval: 1.26–18.55, p = 0.021). Conclusion Systemic ventricle morphology was not associated with the 10-year survival rate after the Fontan procedure. Postoperative thromboembolic events accounted for a 4.84-times higher mortality risk after the Fontan procedure.

Pharmaceutical Innovation and U.S. Cancer Survival, 1992-2003: Evidence from Linked SEER-MEDSTAT Data

2008 ◽  
Vol 10 (1) ◽  
Author(s):  
Frank R. Lichtenberg
Keyword(s):  
Survival Rate ◽  
Radiation Oncology ◽  
Cancer Survival ◽  
Sampling Error ◽  
Weighted Least Squares ◽  
Survival Rates ◽  
Pharmaceutical Innovation ◽  
Diagnostic Radiology ◽  
Medical Innovation ◽  
The Impact

This study examines the impact of pharmaceutical innovation and other factors on the survival of U.S. cancer patients during the period 1992-2003. In particular, it investigates whether cancer survival rates increased more for those cancer sites that had the largest increases in the proportion of chemotherapy treatments that were "new" treatments. We control for other types of medical innovation, i.e. other pharmaceutical innovation, and innovation in surgical procedures, diagnostic radiology procedures, and radiation oncology procedures.Data on observed survival rates, the number of people diagnosed, mean age at diagnosis, and stage distribution are obtained from the National Cancer Institute’s SEER public-use data. Estimates of rates of innovation in chemotherapy and other treatment and diagnostic procedures are constructed from the MEDSTAT MarketScan database and other data sources. Treatment innovation indicators based on MEDSTAT data are likely to be useful, albeit noisy, indicators of the treatment innovation experienced by patients in SEER registries. This sampling error is likely to bias the coefficients on the treatment innovation measures towards zero.We compute weighted least-squares estimates of 6 versions of a survival model, based on different survival intervals and functional forms. The chemotherapy vintage coefficient is positive and significant in every model. This indicates that the cancer sites whose chemotherapy vintage (measured by the share of post-1990 treatments) increased the most during the period 1992-2003 tended to have larger increases in observed survival rates, ceteris paribus.We estimate how much lower the survival rate from all cancer sites combined would have been during 1993-2001 in the absence of post-1992 chemotherapy innovation. The estimates indicate that chemotherapy innovation accounted for 74% of the increase in the 1-year observed survival rate for all cancer sites combined during the period 1992-2001. Chemotherapy innovation accounted for smaller fractions of the increases in the 2-year and 3-year observed survival rates for all cancer sites combined during the same period: 51% and 29%, respectively.The coefficients on measures of non-pharmaceutical medical innovation (in radiation oncology, diagnostic radiology, and surgery innovation) are generally not significant. However these measures may be less reliable than the drug innovation measure. They were based upon the year in which the AMA established a new procedure code, which may be a far less meaningful indicator of innovation than the year in which the FDA first approved a drug. This topic warrants further research.

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