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1.
Rapid Commun Mass Spectrom ; 38(7): e9715, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38351644

RESUMEN

RATIONALE: Polysorbate 80 (PS80) is an amphipathic, nonionic surfactant that is commonly used to stabilize proteins in biopharmaceutical formulations. PS80 undergoes oxidative and/or enzymatic degradation. However, because PS80 is a complex mixture consisting of many constituents, comprehensive evaluations of its oxidative degradation products are difficult and insufficient. METHODS: Our previously reported comprehensive liquid chromatography-tandem mass spectrometry (LC/MS/MS)-based method for PS80 effectively provides an overall profile of PS80 components under simple LC conditions. In this study, we attempted to shorten the analysis time. Furthermore, PS80 was oxidatively degraded in a solution containing histidine and iron, and the oxidative degradation products were evaluated using a modified LC/MS/MS method. In addition, enzymatically hydrolyzed PS80 samples were analyzed. RESULTS: We succeeded in shortening the analysis time from 70 to 20 min while maintaining the resolution of the PS80 components of the same selected reaction monitoring transition. Both the previously reported oxidative degradation products and the newly discovered products were successfully detected, and their composition ratios and changes over time were observed. Changes in the hydrolysates over time are shown in the analysis of the hydrolyzed PS80 samples. CONCLUSIONS: This study clearly showed the presence of changes in PS80 oxidative and/or enzymatic degradation products, including those previously unreported. These results demonstrate that a detailed profiling of PS80 degradation products can be performed using LC/MS/MS, which is less expensive and more generally adopted than high-resolution MS.


Asunto(s)
Polisorbatos , Espectrometría de Masas en Tándem , Polisorbatos/análisis , Polisorbatos/química , Polisorbatos/metabolismo , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Estrés Oxidativo
2.
Braz. j. microbiol ; 47(2): 417-423, Apr.-June 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-780825

RESUMEN

Abstract Various chemical compounds, including surfactants, when introduced to culture media may increase the permeability of cellular membranes and thereby affect the quantity of metabolites excreted by cells. The aim of the present study was to evaluate the impact of detergents including Triton X-100, Span 20 and Tween 80 on erythritol production from glycerol by Yarrowia lipolytica Wratislavia K1 in a shake-flask experiment, batch and fed-batch cultures. When Span 20 was added to a fed-batch culture with glycerol as a carbon source (300 g L-1), erythritol production increased by 15% compared to the culture without the surfactant where it reached 142 g L-1 after 5 days, which corresponded to 0.47 g g-1 yield and productivity of 1.1 g L-1 h-1. Therefore, it was concluded that Span 20 considerably enhanced the production of this polyol from glycerol.


Asunto(s)
Tensoactivos/metabolismo , Medios de Cultivo/metabolismo , Yarrowia/metabolismo , Eritritol/biosíntesis , Manitol/metabolismo , Polisorbatos/análisis , Polisorbatos/metabolismo , Tensoactivos/análisis , Octoxinol/análisis , Octoxinol/metabolismo , Medios de Cultivo/química , Eritritol/análisis , Manitol/análisis
3.
Braz. j. microbiol ; 46(3): 825-834, July-Sept. 2015. tab, ilus
Artículo en Inglés | LILACS | ID: lil-755824

RESUMEN

Lactobacillus sakei subsp. sakei 2a is a bacteriocinogenic lactic acid bacterium isolated from Brazilian pork sausage, capable of inhibiting the growth of microbial pathogens, mainly Listeria monocytogenes. In order to optimize bacteriocin production for industrial applications, this study evaluated the effect of supplementation of MRS broth with glucose, Tween 20, Tween 80, sodium citrate, potassium chloride and cysteine, and effect of the initial pH and temperature of incubation of the medium on production of bacteriocins by L. sakei 2a. Adding glucose and Tween 20 to the medium, an initial pH of 5.0 or 5.5, and incubation temperatures of 25 °C or 30 °C resulted to the highest bacteriocin yields. Thus, a 24 factorial design with the four variables was performed, and statistical analysis showed that it was an adequate model (R2 = 0.8296). In the studied range, the four parameters significantly influenced bacteriocin production, with the maximum yield produced at an initial pH between 5.5 and 7.0, a temperature between 25 and 30 °C and supplementation of the MRS broth with glucose from 3.25 to 6.0 g L−1 and Tween 20 from 0.575 to 1.15% (v/v). Response Surface Methodology analysis indicated that the highest bacteriocin production (12800 AU mL−1) occurred in the MRS broth supplemented with 5.5 g L−1 glucose and 1.05% Tween 20 at an initial pH of 6.28 and an incubation temperature of 25 °C. The amount of bacteriocin produced in commercial MRS broths under the same conditions was only 5600AU mL−1.

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Asunto(s)
Antibacterianos/metabolismo , Bacteriocinas/metabolismo , Medios de Cultivo/metabolismo , Lactobacillus/crecimiento & desarrollo , Lactobacillus/metabolismo , Brasil , Glucosa/metabolismo , Lactobacillus/clasificación , Pruebas de Sensibilidad Microbiana , Polisorbatos/metabolismo , Carne Roja/microbiología , Propiedades de Superficie , Temperatura
4.
Ars pharm ; 41(4): 397-403, oct. 2000.
Artículo en En | IBECS | ID: ibc-23497

RESUMEN

El proceso de liberación de hidrocortisona de los hidrogeles con la adición del 1 por ciento y del 3 por ciento del polisorbato 20 o polisorbato 80, en la presencia de propilenglicol - 1,2 o PEG 200, tiene dos fases. Durante la primera fase las velocidades de liberación son más altas, comparando con la segunda fase. La segunda fase de liberación corresponde a la cinética de primer orden. Los periodos de semiliberación en el transcurso de esta fase oscilan entre 15,67 y 23,50 (AU)


Asunto(s)
Humanos , Hidrocortisona , Hidrogeles/metabolismo , Polisorbatos/metabolismo , Propilenglicol/metabolismo
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