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1.
J Biotechnol ; 393: 17-30, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39025368

RESUMEN

Ricinoleic acid (RA) from castor oil was employed in biotransformation of peach-flavoured γ-decalactone (GDL), using a Candida parapsilosis strain (MTCC13027) which was isolated from waste of pineapple crown base. Using four variables-pH, cell density, amount of RA, and temperature-the biotransformation parameters were optimized using RSM and BBD. Under optimized conditions (pH 6, 10 % of microbial cells, 10 g/L RA at 28°C), the conversion was maximum and resulted to 80 % (+)-GDL (4.4 g/L/120 h) yield in shake flask (500 mL). Furthermore, optimization was achieved by adjusting the aeration and agitation parameters in a 3 L bioreactor, which were then replicated in a 10 L bioreactor to accurately determine the amount of (+)-GDL. In bioreactor condition, 4.7 g/L (>85 %) of (+)-GDL is produced with 20 % and 40 % dissolved oxygen (1.0 vvm) at 150 rpm in 72 h and 66 h, respectively. Further, a new Al-Mg-Ca-Si composite column-chromatography method is developed to purify enantiospecific (+)-GDL (99.9 %). This (+)-GDL is 100 % nature-identical as validated through 14C-radio-carbon dating. Thorough chemical investigation of enantiospecific (+)-GDL is authenticated for its use as flavour. This bioflavour has been developed through a cost-effective biotechnological process in response to the demand from the food industry on commercial scale.


Asunto(s)
Reactores Biológicos , Candida parapsilosis , Aceite de Ricino , Lactonas , Ácidos Ricinoleicos , Ácidos Ricinoleicos/metabolismo , Ácidos Ricinoleicos/química , Reactores Biológicos/microbiología , Aceite de Ricino/química , Aceite de Ricino/metabolismo , Candida parapsilosis/metabolismo , Lactonas/metabolismo , Lactonas/química , Aromatizantes/metabolismo , Aromatizantes/química , Biotransformación
2.
Artículo en Inglés | MEDLINE | ID: mdl-38507391

RESUMEN

PGPR is an emulsifier (E476) widely used in the food industry. In this study, a gas chromatography-flame ionisation detection (GC-FID) method was developed for the quantitative characterisation of the polyglycerol composition of PGPR. The method was validated to analyse quantitatively the polyglycerol species in neat PGPR products and in PGPR samples present in a lipid matrix. This method consists of saponification, acidification and petroleum ether extraction to remove interfering fatty acids, neutralisation, silylation and finally GC-FID analysis. Phenyl ß-D-glucopyranoside was used as internal standard as sorbitol proved unsuitable due to its susceptibility to interference from Na/K chloride during silylation. The response factors of glycerol and diglycerol towards phenyl ß-D-glucopyranoside were determined using pure standards, while response factors of polyglycerols with a degree of polymerisation of at least 3 could be reliably estimated according to an effective carbon number (ECN) approach. The validity of the method applied to PGPR samples was further supported on the basis of a mass balance considering the experimentally determined polyglycerol and fatty acid content. Moreover, recoveries of di-, tri-, tetra- and pentaglycerol were more than 95% for various PGPR samples added to two different lipid matrices at 2 wt% and 5 wt% concentrations. Furthermore, the method proved to be very repeatable (with relative standard deviation values below 2.2%). On the other hand, the inevitable presence of glycerol in the lipid samples caused fouling of the detector and column overloading, requiring frequent cleaning of the detector and trimming off part of the column.


Asunto(s)
Glicerol , Lípidos , Polímeros , Glicerol/análisis , Glicerol/análogos & derivados , Polímeros/química , Cromatografía de Gases , Lípidos/análisis , Lípidos/química , Ácidos Ricinoleicos/análisis , Ácidos Ricinoleicos/química , Ionización de Llama
3.
Compr Rev Food Sci Food Saf ; 22(6): 4282-4301, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37583303

RESUMEN

Polyglycerol polyricinoleate (PGPR) is a synthetic food additive containing a complex mixture of various esters. In recent years, there has been a growing trend to use PGPR-stabilized water-in-oil (W/O) emulsions to replace fat in order to produce low-calorie food products. In this respect, it is essential to comprehensively characterize the PGPR molecular species composition, which might enable to reduce its required amount in emulsions and foods based on a better understanding of the structure-activity relationship. This review presents the recent research progress on the characterization and quantitative analysis of PGPR. The influencing factors of the emulsifying ability of PGPR in W/O emulsions are further illustrated to provide new insights on the total or partial replacement of PGPR. Moreover, the latest progress on applications of PGPR in food products is described. Current studies have revealed the complex structure of PGPR. Besides, recent research has focused on the quantitative determination of the composition of PGPR and the quantification of the PGPR concentration in foods. However, research on the quantitative determination of the (poly)glycerol composition of PGPR and of the individual molecular species present in PGPR is still limited. Some natural water- or oil-soluble surfactants (e.g., proteins or lecithin) have been proven to enable the partial replacement of PGPR in W/O emulsions. Additionally, water-dispersible phytosterol particles and lecithin have been successfully used as a substitute of PGPR to create stable W/O emulsions.


Asunto(s)
Glicerol , Lecitinas , Glicerol/química , Ácidos Ricinoleicos/química , Emulsiones/química , Agua/química
4.
Biomacromolecules ; 23(8): 3417-3428, 2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35881559

RESUMEN

The alternating architecture and hydrophobic side chains hinder hydrolytic cleavage and anhydride interchange in poly(sebacic acid-ricinoleic acid) (P(SA-RA)), which provides stable polyanhydrides at room temperature. In this report, a series of polyanhydrides were designed to investigate the effect of ester bonds, hydrophobic side chains, phenyl moieties, and their distance from anhydride bonds on their stability and properties. Polyanhydrides with alternating architecture are constructed by the polymerization of ester-diacids prepared from ricinoleic or other hydroxy acids with anhydrides such as succinic, maleic, and phthalic anhydrides. The hydrophobic side chains are designed closer to anhydride bonds to investigate hindrance to hydrolytic cleavage and anhydride interchange. Polyanhydrides were obtained by the activation of ester-diacid using acetic anhydride followed by melt condensation. The reactions were monitored by NMR, Fourier transform infrared (FTIR), and gel permeation chromatography (GPC). The synthesized poly(ester-anhydride)s with a shorter chain length compared to P(SA-RA) were stable at room temperature. The hydrolytic degradation studies reveal that the phenyl moiety present in poly(ricinoleic acid phthalate) (PRAP) and poly(hydroxystearic acid phthalate) (PHSAP) reduces the hydrolysis of anhydride bonds. Poly(hydroxyoctanoic acid succinate) (PHOAS) demonstrates the highest molecular weight of all tested polymers. The results reveal that the presence of hydrophobic side chains, phenyl moieties, and their distance from anhydride bonds significantly improves the stability. These stable polyanhydrides can provide convenience to use in control drug-delivery applications. The in vitro drug release study using ibuprofen shows that polymers with aromatic units such as PRAP and PHSAP establish sustained release, which presents more than 50 and 40% of ibuprofen over a period of 28 days.


Asunto(s)
Anhídridos , Polianhídridos , Anhídridos/química , Ésteres/química , Hidroxiácidos , Ibuprofeno , Ácidos Ricinoleicos/química
5.
Sci Rep ; 12(1): 11946, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35831366

RESUMEN

In this study, effects of sesamol on improving the oxidative stability of sunflower oil and its oil-in-water emulsion was investigated. To investigate the kinetic parameters related to the initiation and propagation stages of oxidation, a sigmoidal-model was used. Sesamol exhibited higher antioxidant activity in sunflower oil-in-water emulsion than that of sunflower oil. In both sunflower oil and sunflower oil-in-water emulsion, the inhibitory effect of sesamol against lipid oxidation continued even after the induction period. To improve the efficiency of sesamol in sunflower oil, polyglycerol polyricinoleate (PGPR) was incorporated into the functional environment of the sesamol. Sesamol exhibited a synergistic effect with PGPR during both initiation (synergistic effect of 68.87%) and propagation (synergistic effect of 36.84%) stages. Comparison of the size of reverse micelles in samples containing PGPR with those without PGPR revealed that PGPR can enhance the efficiency of sesamol by increasing the acceptance capacity of lipid hydroperoxides in reveres micelles structures. This can result in enhancing the effective collisions between sesamol and lipid hydroperoxides in the presence of PGPR. The water produced as a major byproduct of oxidation played a key role on the antioxidant activity of sesamol alone or in combination with PGPR during oxidation process.


Asunto(s)
Antioxidantes , Micelas , Antioxidantes/farmacología , Benzodioxoles , Emulsiones/química , Glicerol/análogos & derivados , Fenoles , Ácidos Ricinoleicos/química , Aceite de Girasol , Agua/química
6.
Int J Biol Macromol ; 186: 759-769, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34271051

RESUMEN

The present work aims to fabricate the genipin-crosslinked alkaline soluble polysaccharides-whey protein isolate conjugates (G-AWC) to stabilize W/O/W emulsions for encapsulation and delivery of grape seed proanthocyanidins (GSP). After crosslinking reaction, the molecular weight was increased and surface hydrophobicity was decreased. Then, the G-AWC and polyglycerol polyricinoleate (PGPR, a lipophilic emulsifier) were employed to prepare a GSP-loaded W/O/W emulsion with the addition of gelatin and sucrose in W1 phase via a two-step procedure. Creamed emulsion could be fabricated at W1/O volume fraction (Φ) of 10%-70% and further increased Φ to 75% or even up to 90% could obtain gel-like emulsion with notably elastic behaviors. In the W1/O/W2 emulsion with Φ of 80%, the encapsulation efficiency (EE) of GSP reached up to 95.86%, and decreased by ca. 10% after a week of storage. Moreover, the encapsulated GSP in the emulsion showed a remarkably higher bioaccessibility (40.72%) compared to free GSP (13.11%) in the simulated gastrointestinal digestion. These results indicated that G-AWC-stabilized W/O/W emulsions could be an effective carrier to encapsulate water-soluble bioactive compounds with enhanced stability and bioaccessibility.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Digestión , Manipulación de Alimentos , Extracto de Semillas de Uva/química , Iridoides/química , Aceites/química , Polisacáridos/química , Proantocianidinas/química , Agua/química , Proteína de Suero de Leche/química , Disponibilidad Biológica , Emulsionantes/química , Emulsiones , Jugo Gástrico/química , Geles , Glicerol/análogos & derivados , Glicerol/química , Concentración de Iones de Hidrógeno , Secreciones Intestinales/química , Lipólisis , Ácidos Ricinoleicos/química , Solubilidad
7.
Artículo en Inglés | MEDLINE | ID: mdl-34266373

RESUMEN

Polyglycerol polyricinoleate (PGPR) is a powerful lipophilic emulsifier used in low-fat spreads and chocolate. It should be used at the lowest level at which the desired technological effect is achieved, not exceeding the specified maxima according to Annexe II to Regulation (EC) No 1333/2008. A gas chromatography-flame ionisation detection (GC-FID) method was developed for quantification of PGPR. This method is based on estimating the content of ricinoleic acid using 12-hydroxyoctadecanoic acid as an internal standard, from which the PGPR concentration was deduced. The method involved saponification, methylation, a two-step solid phase extraction (SPE) separation of the fatty acid methyl esters (FAMEs), silylation, and GC-FID analysis. The limits of detection and quantification of ricinoleic acid were 2.2 and 6.7 µg/mL, respectively, at 0.1 µL injection volume. Considering the average content of ricinoleic acid in PGPR (i.e. 86.63 ± 2.0 wt%) and the amount of food product that is used in the proposed protocol (i.e. 20 mg), this resulted in a LOD and LOQ of 0.76 and 2.32 µg PGPR per mg of food product, respectively. The developed method was validated by determining PGPR recovery from a high oleic sunflower oil (HOSO) solution, from chocolate spiked with a commercially available PGPR, and from commercially available low fat spreads with a known PGPR content. The actual recovery was more than 95% for all matrices, indicating the accuracy of the developed analytical technique. Moreover, the method proved to be very reproducible, with RSD < 4% for concentrations ranging from 0.2 to 5 wt%. The results showed that our proposed GC-FID method enables the reliable and quantitative determination of the PGPR concentration in commercial food products with various fat contents.


Asunto(s)
Cromatografía de Gases/métodos , Análisis de los Alimentos/métodos , Glicerol/análogos & derivados , Ácidos Ricinoleicos/química , Emulsionantes , Glicerol/análisis , Humanos , Estructura Molecular , Reproducibilidad de los Resultados , Ácidos Ricinoleicos/análisis
8.
J Biomater Appl ; 36(3): 385-405, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33530824

RESUMEN

Nosocominal infections associated with biofilm formation on urinary catheters cause serious complications. The aim of this study was to investigate the feasibility of the polyurethane (PU) catheter modified with tetracycline hydrochloride (TCH) attached Ag nanoparticles embedded PolyRicinoleic acid-Polystyrene Nanoparticles (PU-TCH-AgNPs-PRici-PS NPs) and the influence on antimicrobial and antibiofilm activity of urinary catheters infected by Escherichia coli and Staphylococcus aureus. For this purpose, AgNPs embedded PRici graft PS graft copolymers (AgNPs-PRici-g-PS) were synthesized via free radical polymerization and characterized by FTIR, HNMR and DSC. AgNPs-PRici-PS NPs were prepared and optimized by the different parameters and the optimized size of nanoparticle was found as about 150 ± 1 nm. The characterization of the nanoparticles and the morphological evaluation were carried out by FTIR and SEM. Short term stability of nanoparticles was realised at 4°C for 30 days. In vitro release profiles of TCH and Ag NPs were also investigated. The formation of biofilm on PU modified TCH-Ag NPs-PRici-PS NPs, was evaluated and the biocompatibility test of the nanoparticles was realized via the mouse fibroblast (L929) and mouse urinary bladder cells (G/G An1). This is the first time that TCH-AgNPs-PRici-PS NPs used in the modification of PU catheter demonstrated high antimicrobial and antibiofilm activities against the urinary tract infection.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Relacionadas con Catéteres/prevención & control , Poliestirenos/química , Ácidos Ricinoleicos/química , Plata/administración & dosificación , Infecciones Urinarias/prevención & control , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Catéteres/efectos adversos , Catéteres/microbiología , Línea Celular , Portadores de Fármacos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Ratones , Nanopartículas/química , Plata/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología
9.
Food Chem ; 327: 127014, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32434126

RESUMEN

The influence of diacylglycerol (DAG) combined with polyglycerol polyricinoleate (PGPR) on the stability of water-in-oil (W/O) emulsions containing hydrogenated palm oil (HPO) was studied. Polarized light microscope revealed that DAG promoted HPO to crystallize at the water-oil interface, providing the combination of Pickering and network stabilization effects. It was proposed that the molecular compatibility of fatty acids in DAG with HPO accounted for the promotional effect. The interfacial crystallization of DAG together with the surface activity of PGPR led to the formation of emulsions with uniform small droplets and high freeze-thaw stability. Further exploration of physical properties indicated that the combination of DAG and PGPR dramatically improved the emulsion's viscoelasticity and obtained a larger deformation yield. Water droplets in DAG-based emulsions acted as active fillers to improve the network rigidity. Therefore, DAG is a promising material to be used as emulsifier to enhance the physical stability of W/O emulsions.


Asunto(s)
Diglicéridos/química , Emulsiones/química , Cristalización , Congelación , Glicerol/análogos & derivados , Glicerol/química , Aceite de Palma/química , Aceite de Brassica napus/química , Ácidos Ricinoleicos/química , Viscosidad , Agua/química
10.
Chirality ; 32(7): 998-1007, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32250002

RESUMEN

(R)-ricinoleic acid is the main component of castor oil from Ricinus communis L. Due to the presence of the hydroxyl group in homoallylic position and asymmetrically substituted carbon atom, it may undergo a number of chemical and biochemical transformations resulting in the products with some specific bioactivities. Conversion of (R)-ricinoleic acid into its (S)-enantiomer enables synthesis of both (R)- and (S)-ricinoleic acid derivatives and comparison of their biological activities. In the present research, (R)- and (S)-ricinoleic acid amides synthesized from methyl ricinoleates and ethanolamine or pyrrolidine as well as acetate derivatives of ethanolamine amides were studied to demonstrate their biological activities using HT29 cancer cells. Double staining of cells with fluorochromes (Hoechst 33258/propidium iodide) as well as 2,'7'-dichlorodihydrofluorescein (DCF) and comet assays were performed. Both the tested amides and acetates caused DNA damage and induced apoptotic and necrotic cell death. In the case of (R)- and (S)-enantiomers of one of the tested acetates, significant difference in the ability to induce DNA damage was observed, which showed the impact of the stereogenic center on the activities of these compounds.


Asunto(s)
Acetatos/química , Amidas/química , Antineoplásicos/farmacología , Aceite de Ricino/química , Ácidos Ricinoleicos/química , Antineoplásicos/química , Daño del ADN/efectos de los fármacos , Células HT29 , Humanos , Ácidos Ricinoleicos/toxicidad , Estereoisomerismo
11.
Biotechnol Lett ; 42(8): 1547-1558, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32246345

RESUMEN

Microbial production of hydroxy fatty acids (HFAs) was widely studied because of important biological properties of HFAs. Among microorganisms producing HFAs, Pseudomonas aeruginosa PR3 was well known to produce various HFAs from different unsaturated fatty acids. Recently, a new variant species of P. aeruginosa PR3 was isolated and characterized, showing improved efficiency for producing 7,10-dihydroxy-8(E)-octadecenoic acid from oleic acid. In this study, we report the production of 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD) from ricinoleic acid by the newly isolated P. aeruginosa KNU-2B. TOD was efficiently produced from ricinoleic acid by KNU-2B with the maximum conversion yield of 56.7% under the optimum reaction conditions of pH 8.0 and 48-h incubation at 27 °C, 150 rpm. Under optimized reaction conditions, maximum TOD production reached 340.3 mg/100 mL of the culture. However, requirement of nutritional factors by KNU-2B for production of TOD were considerably different from those by PR3 strain.


Asunto(s)
Hidroxiácidos , Ácidos Oléicos , Pseudomonas aeruginosa/metabolismo , Ácidos Ricinoleicos , Hidroxiácidos/análisis , Hidroxiácidos/química , Hidroxiácidos/metabolismo , Ácidos Oléicos/análisis , Ácidos Oléicos/química , Ácidos Oléicos/metabolismo , Ácidos Ricinoleicos/química , Ácidos Ricinoleicos/metabolismo
12.
Lipids ; 55(5): 537-548, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32115716

RESUMEN

Castor oil contains approximately 90% ricinoleic acid (RA) which is stored mainly in the form of tri-ricinoleic acid containing triacylglycerols (TAG). Ricinoleate is synthesized from oleate (18:1n-9) esterified to the sn-2 position of phosphatidylcholine (PtdCho) catalyzed by oleoyl-12-hydroxylase. PtdCho-derived diacylglycerol (DAG) is an important substrate pool for TAG synthesis, and the interconversion between PtdCho and DAG has been shown to play a critical role in channeling hydroxy fatty acids (HFA) to TAG. Although phospholipase D (PLD) has been reported to catalyze the hydrolysis of PtdCho to produce phosphatidic acid which can then be converted to DAG, its potential functions in the channeling of RA from PtdCho to DAG and the assembly of RA on TAG is largely unknown. In the present study, 11 PLD genes were identified from the Castor Bean Genome Database. Gene expression analysis indicated that RcPLD9 is expressed at relatively high levels in developing seeds compared to other plant tissues. Sequence and phylogenetic analyses revealed that RcPLD9 is a homolog of Arabidopsis PLDζ2. Overexpression of RcPLD9 in the Arabidopsis CL7 line producing C18-HFA resulted in RA content reductions in the polar lipid fraction (mainly PtdCho) and mono-HFA-TAG, but increased RA content in di-HFA-TAG. Since part of RA in di-HFA-TAG is derived from HFA-DAG, the results indicated that RcPLD9 facilitates the channeling of RA from PtdCho to DAG for its assembly on TAG in developing seeds.


Asunto(s)
Proteínas de Arabidopsis/genética , Fosfolipasa D/genética , Ácidos Ricinoleicos/metabolismo , Ricinus communis/genética , Triglicéridos/metabolismo , Arabidopsis/genética , Ricinus communis/metabolismo , Aceite de Ricino/química , Aceite de Ricino/genética , Aceite de Ricino/metabolismo , Endospermo/genética , Endospermo/metabolismo , Ácidos Grasos/genética , Ácidos Grasos/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Ácidos Ricinoleicos/química , Semillas/genética , Semillas/metabolismo , Triglicéridos/genética
13.
Mar Drugs ; 18(2)2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-32075231

RESUMEN

A series of novel substituted 1-O-alkylglycerols (AKGs) containing methoxy (8), gem-difluoro (9), azide (10) and hydroxy (11) group at 12 position in the alkyl chain were synthesized from commercially available ricinoleic acid (12). The structures of these new synthesized AKGs were established by NMR experiments as well as from the HRMS and elementary analysis data. The antimicrobial activities of the studied AKGs 8-11 were evaluated, respectively, and all compounds exhibited antimicrobial activity to different extents alone and also when combined with some commonly used antibiotics (gentamicin, tetracycline, ciprofloxacin and ampicillin). AKG 11 was viewed as a lead compound for this series as it exhibited significantly higher antimicrobial activity than compounds 8-10.


Asunto(s)
Antibacterianos/farmacología , Glicerol/análogos & derivados , Glicerol/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Ácidos Ricinoleicos/química , Ácidos Ricinoleicos/farmacología , Ácidos Ricinoleicos/síntesis química
14.
Food Chem ; 314: 126174, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31981885

RESUMEN

The aim of this work is to develop a W1/O/W2 multiple emulsion with gallic acid in the internal aqueous phase (W1). A quantification method for gallic acid using HPLC-UV was developed and validated. In the first step, a simple W1/O emulsion was prepared with distilled water, polyglycerol polyricinoleate, sodium chloride, gallic acid and pH 5.0 sodium acetate buffer system. The second step consisted of adding the simple emulsion to the external aqueous phase (W2) composed of distilled water, polysorbate 80 and xanthan gum. The multiple emulsion showed pseudoplastic behavior. After 28 days of analysis the multiple emulsion presented a stability index of 75% without pH variation, 89.61% of gallic acid concentration, 59.62% of antioxidant activity in the phosphomolybdenum complex assay and 80.58% of DPPH scavenging activity. It is concluded that the W1/O/W2 emulsion developed was stable for 28 days and maintained more than 50% of gallic acid antioxidant capacity.


Asunto(s)
Ácido Gálico/química , Emulsiones , Glicerol/análogos & derivados , Glicerol/química , Aceite de Brassica napus/química , Ácidos Ricinoleicos/química , Cloruro de Sodio/química , Viscosidad , Agua/química
15.
Angew Chem Int Ed Engl ; 59(18): 7024-7028, 2020 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-31957098

RESUMEN

Long-chain aliphatic amines such as (S,Z)-heptadec-9-en-7-amine and 9-aminoheptadecane were synthesized from ricinoleic acid and oleic acid, respectively, by whole-cell cascade reactions using the combination of an alcohol dehydrogenase (ADH) from Micrococcus luteus, an engineered amine transaminase from Vibrio fluvialis (Vf-ATA), and a photoactivated decarboxylase from Chlorella variabilis NC64A (Cv-FAP) in a one-pot process. In addition, long chain aliphatic esters such as 10-(heptanoyloxy)dec-8-ene and octylnonanoate were prepared from ricinoleic acid and oleic acid, respectively, by using the combination of the ADH, a Baeyer-Villiger monooxygenase variant from Pseudomonas putida KT2440, and the Cv-FAP. The target compounds were produced at rates of up to 37 U g-1 dry cells with conversions up to 90 %. Therefore, this study contributes to the preparation of industrially relevant long-chain aliphatic chiral amines and esters from renewable fatty acid resources.


Asunto(s)
Alcohol Deshidrogenasa/metabolismo , Aminas/metabolismo , Carboxiliasas/metabolismo , Ésteres/metabolismo , Ácido Oléico/metabolismo , Ácidos Ricinoleicos/metabolismo , Aminas/química , Chlorella/enzimología , Ésteres/química , Micrococcus luteus/enzimología , Estructura Molecular , Ácido Oléico/química , Procesos Fotoquímicos , Ácidos Ricinoleicos/química
16.
Prep Biochem Biotechnol ; 50(4): 401-407, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31829798

RESUMEN

In the present study, we report a reverse-phase high-performance liquid chromatography (RP-HPLC) method for separation of the regio-isomers of Glyceryl MonoRicinoleate (GMR) identified using position specificity of lipases. The approaches explored to identify these regio-isomers include LC-mass spectrometry, UV spectroscopy, and selective hydrolysis with lipases. A distinct UV absorption spectrum and λmax values for each isomer were noted, and mass spectral analysis further revealed their molecular weight. Lastly, the purified regio-isomers were subjected to hydrolysis with two distinctive regio-specific lipases to identified as sn-2 and sn-1(3) GMR. The current methodology of using analytic tool and enzyme specificity provides a useful platform for identifying regio-isomers for structured lipid synthesis.


Asunto(s)
Glicéridos/análisis , Lipasa/química , Ácidos Ricinoleicos/análisis , Aceite de Ricino/química , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Glicéridos/química , Hidrólisis , Isomerismo , Ácidos Ricinoleicos/química , Ricinus/química
17.
Int J Biol Macromol ; 152: 1233-1241, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31765743

RESUMEN

In this study, anthocyanin-loaded water1-in-oil-in-water2 (W1/O/W2) double Pickering emulsions stabilized by octenylsuccinate quinoa starch (OSQS) were optimized, and their storage stability and in vitro gastrointestinal digestion were evaluated. Novel starch-based double emulsions as anthocyanin cargos were achieved at 2% (w/v of oil) of polyglycerol polyricinoleate concentration, the W1/O volume proportion of 3:7, 6% (w/v of total volume) of OSQS concentration, and the volume proportion of (W1/O): W2 = 6:4 and 5:5. CLSM results evidenced the formation of double Pickering emulsions, and the significant decreases in the encapsulation stability of anthocyanins were closely related to the increases in the droplet size induced by osmotic pressure. Less than 15% of anthocyanins in the double Pickering emulsions was released after incubated for 60 min under simulated stomach conditions; controlled-release of anthocyanins was observed during the 120 min of simulated intestinal digestion, consistent with starch hydrolysis data. These findings will be useful for designing starch-based double Pickering emulsion with intestinal-targeted delivery as a novel carrier of sensitive hydrophilic bioactive compounds.


Asunto(s)
Antocianinas/química , Chenopodium quinoa/química , Digestión/efectos de los fármacos , Emulsionantes/química , Emulsiones/química , Almidón/química , Composición de Medicamentos/métodos , Glicerol/análogos & derivados , Glicerol/química , Hidrólisis/efectos de los fármacos , Presión Osmótica/efectos de los fármacos , Tamaño de la Partícula , Ácidos Ricinoleicos/química , Agua/química
18.
Biomolecules ; 9(10)2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31590242

RESUMEN

In addition to our previous efforts toward bioenzymatic and chemical transformations of ricinoleic acid and oleic acid to their corresponding ,-dicarboxylic acids via their ester intermediates driven in Escherichiacoli cells, several efficient oxidation conditions were investigated and optimized for the conversion of -hydroxycarboxylic acids to ,-dicarboxylic acids. Pd/C-catalyzed oxidation using NaBH4 in a basic aqueous alcohol and Ni(II) salt-catalyzed oxidation using aqueous sodium hypochlorite were considered to be excellent as a hybrid reaction for three successive chemical reactions (hydrogenation, hydrolysis, and oxidation) and an eco-friendly, cost-effective, and practical approach, respectively. Omega-hydroxycarboxylic acids and -aminocarboxylic acid were also easily prepared as useful building blocks for plastics or bioactive compounds from the bioenzymatically driven ester intermediate. The scope of the developed synthetic methods can be utilized for large-scale synthesis and various derivatizations.


Asunto(s)
Borohidruros/química , Ácidos Dicarboxílicos/química , Ácidos Ricinoleicos/química , Tecnología Química Verde , Hidrogenación , Hidrólisis , Oxidación-Reducción
19.
Food Funct ; 10(7): 4242-4255, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31259325

RESUMEN

Water-in-oil-in-water emulsions containing an internalised salt solution were stabilised with non-chemically modified waxy rice starch (WRS), and octinyl succinic anhydride (OSA) as reference, to release salt during oral processing due to amylase-induced destabilisation. Salt levels were 1.5 g salt and 0.47 g salt per 100 g external and internal aqueous phases, respectively. Variables were the starch content (2, 3, 4 g per 100 g emulsion; 20 g oil per 100 g emulsion), level of polyglycerol polyricinoleate (PGPR) as a lipophilic emulsifier (0.29, 0.57 g per 100 g emulsion) and ambient-pressure processing temperature for WRS gelatinisation, the non-chemical modification process, (75 ± 3, 88 ± 5 °C). OSA starch was used under previously applied conditions (2, 3, 4 g starch, 0.57 g PGPR per 100 g emulsion, 25 ± 5 °C). Emulsions were stable for three months, except OSA and lower level PGPR low temperature processed WRS emulsions lost salt into the external emulsion phase. One day after processing, encapsulation efficiency (EE) was as predicted from the composition for OSA emulsions, while at the same PGPR content an external aqueous phase was incorporated into the oil droplets of the WRS emulsion increasing EE. Salt release was assessed in vitro and through sensory evaluation using paired comparison testing. The results revealed that the efficacy of this salt reduction approach was enhanced for gelatinised WRS compared to OSA starch stabilised emulsions. Consumer tests on a tomato soup, to validate this salt reduction approach for a real food, revealed a possible 25% salt reduction, compared to current UK products.


Asunto(s)
Oryza/química , Cloruro de Sodio/análisis , Almidón/química , Adulto , Anciano , Comportamiento del Consumidor , Emulsionantes/química , Emulsiones , Femenino , Aditivos Alimentarios/análisis , Glicerol/análogos & derivados , Glicerol/química , Humanos , Masculino , Persona de Mediana Edad , Tamaño de la Partícula , Ácidos Ricinoleicos/química , Anhídridos Succínicos/análisis , Gusto , Viscosidad , Agua/química , Adulto Joven
20.
J Agric Food Chem ; 67(33): 9325-9334, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31318196

RESUMEN

In vitro dynamic aroma release over oil-in-water (o/w) and water-in-oil-in-water (w/o/w) emulsions stabilized with Tween 20 or octenyl succinic anhydride (OSA) starch as a hydrophilic emulsifier and polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier was investigated. The equal-molecular-weight hydrophilic aroma diacetyl (2,3-butanedione) or relatively more-hydrophobic 3-pentanone was added to the emulsions prepared by high speed mixing, or membrane emulsification followed by thickened with xanthan gum removing droplet size distribution and creaming as variables affecting dynamic release. Results showed the differences of w/o/w emulsions in the dynamic release compared to o/w emulsions mainly depended on aroma hydrophobicity, emulsion type, emulsifier-aroma interactions, and creaming. Xanthan led to a reduced headspace replenishment. Interfacially adsorbed OSA starch and xanthan-OSA starch interaction influenced on diacetyl release over emulsions. OSA starch alone interacted with 3-pentanone. This study demonstrates the potential impact of emulsifying and thickening systems on aroma release systems and highlights that specific interactions may compromise product quality.


Asunto(s)
Emulsionantes/química , Odorantes/análisis , Almidón/química , Emulsiones/química , Glicerol/análogos & derivados , Glicerol/química , Interacciones Hidrofóbicas e Hidrofílicas , Polisacáridos Bacterianos/química , Polisorbatos/química , Ácidos Ricinoleicos/química , Anhídridos Succínicos/química , Agua/química
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