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1.
Food Chem ; 251: 41-50, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29426422

RESUMO

Efficiency and effectiveness of collagen extraction process contribute to huge impacts to the quality, supply and cost of the collagen produced. Jellyfish is a potential sustainable source of collagen where their applications are not limited by religious constraints and threats of transmittable diseases. The present study compared the extraction yield, physico-chemical properties and toxicology in vitro of collagens obtained by the conventional acid-assisted and pepsin-assisted extraction to an improved physical-aided extraction process. By increasing physical intervention, the production yield increased significantly compared to the conventional extraction processes (p < .05). Collagen extracted using the improved process was found to possess similar proximate and amino acids composition to those extracted using pepsin (p > .05) while retaining high molecular weight distributions and polypeptide profiles similar to those extracted using only acid. Moreover, they exhibited better appearance, instrumental colour and were found to be non-toxic in vitro and free of heavy metal contamination.


Assuntos
Colágeno/química , Colágeno/isolamento & purificação , Cifozoários/química , Aminoácidos/análise , Animais , Colágeno/toxicidade , Camundongos , Peso Molecular , Pepsina A/química , Solubilidade , Testes de Toxicidade
2.
J Pharm Biomed Anal ; 129: 389-397, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27454091

RESUMO

A detailed procedure for estimating uncertainty according to the Laboratory of Government Chemists/Valid Analytical Measurement (LGC/VAM) protocol for determination of 18 amino acids in gelatin is proposed. The expanded uncertainty was estimated using mainly the method validation data (precision and trueness). Other sources of uncertainties were contributed by components in standard preparation measurements. The method scope covered a single matrix (gelatin) under a wide range of analyte concentrations. The uncertainty of method precision, µ(P) was 0.0237-0.1128pmolµl(-1) in which hydroxyproline and histidine represented the lowest and highest values of uncertainties, respectively. Proline and phenylalanine represented the lowest and highest uncertainties value for method recovery, µ(R) that was estimated within 0.0064-0.0995pmolµl(-1). The uncertainties from other sources, µ(Std) were 0.0325, 0.0428 and 0.0413pmolµl(-1) that were contributed by hydroxyproline, other amino acids and cystine, respectively. Hydroxyproline and phenylalanine represented the lowest and highest values of expanded uncertainty, U(y) that were determined at 0.0949 and 0.2473pmolµl(-1), respectively. The data were accurately defined and fulfill the technical requirements of ISO 17025:2005.


Assuntos
Aminoácidos/química , Aminoquinolinas/química , Carbamatos/química , Gelatina/química , Cromatografia de Fase Reversa/métodos , Hidroxiprolina/química , Indicadores e Reagentes/química , Padrões de Referência , Reprodutibilidade dos Testes , Incerteza
3.
Food Chem ; 196: 953-60, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26593577

RESUMO

The study aimed to evaluate nutraceutical potential of three commercially significant edible jellyfish species (Acromitus hardenbergi, Rhopilema hispidum and Rhopilema esculentum). The bell and oral arms of these jellyfishes were analyzed for their proximate composition, calorific value, collagen content, amino acid profile, chemical score and elemental constituent. In general, all jellyfish possessed low calorific values (1.0-4.9 kcal/g D.W.) and negligible fat contents (0.4-1.8 g/100 g D.W.), while protein (20.0-53.9 g/100 g D.W.) and minerals (15.9-57.2g/100g D.W.) were found to be the richest components. Total collagen content of edible jellyfish varied from 122.64 to 693.92 mg/g D.W., accounting for approximately half its total protein content. The dominant amino acids in both bell and oral arms of all jellyfish studied includes glycine, glutamate, threonine, proline, aspartate and arginine, while the major elements were sodium, potassium, chlorine, magnesium, sulfur, zinc and silicon. Among the jellyfish, A. hardenbergi exhibited significantly higher total amino acids, chemical scores and collagen content (p<0.05) compared to R. hispidum and R. esculentum. Having good protein quality and low calories, edible jellyfish is an appealing source of nutritive ingredients for the development of oral formulations, nutricosmetics and functional food.


Assuntos
Colágeno/química , Valor Nutritivo , Cifozoários/química , Aminoácidos , Animais , Magnésio/análise , Minerais/análise , Potássio/análise , Sódio/análise , Enxofre , Zinco
4.
Food Chem ; 172: 368-76, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25442566

RESUMO

The amino acid compositions of bovine, porcine and fish gelatin were determined by amino acid analysis using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as derivatization reagent. Sixteen amino acids were identified with similar spectral chromatograms. Data pre-treatment via centering and transformation of data by normalization were performed to provide data that are more suitable for analysis and easier to be interpreted. Principal component analysis (PCA) transformed the original data matrix into a number of principal components (PCs). Three principal components (PCs) described 96.5% of the total variance, and 2 PCs (91%) explained the highest variances. The PCA model demonstrated the relationships among amino acids in the correlation loadings plot to the group of gelatins in the scores plot. Fish gelatin was correlated to threonine, serine and methionine on the positive side of PC1; bovine gelatin was correlated to the non-polar side chains amino acids that were proline, hydroxyproline, leucine, isoleucine and valine on the negative side of PC1 and porcine gelatin was correlated to the polar side chains amino acids that were aspartate, glutamic acid, lysine and tyrosine on the negative side of PC2. Verification on the database using 12 samples from commercial products gelatin-based had confirmed the grouping patterns and the variables correlations. Therefore, this quantitative method is very useful as a screening method to determine gelatin from various sources.


Assuntos
Aminoácidos/análise , Aminoquinolinas/química , Carbamatos/química , Cromatografia Líquida de Alta Pressão , Tecnologia de Alimentos/métodos , Gelatina/química , Animais , Bovinos , Cromatografia de Fase Reversa , Peixes , Análise de Componente Principal , Alimentos Marinhos/análise , Suínos
5.
J Chromatogr A ; 1353: 49-56, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24797394

RESUMO

In-house method validation was conducted to determine amino acid composition in gelatin by a pre-column derivatization procedure with the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate reagent. The analytical parameters revealed that the validated method was capable of selectively performing a good chromatographic separation for 18 amino acids in less than 40 min; the overall detection and quantitation limit for amino acids fell into ranges of 5.68-12.48 and 36.0-39.0 pmol/µl, respectively; the matrix effect was not observed, and the linearity range was 37.5-1000 pmol/µl. The accuracy (precision and recovery) analyses of the method were conducted under repeatable conditions on different days in random order. Method precision revealed by HorRat values was significantly less than 2, except for histidine with a precision of 2.19, and the method recoveries had a range of 80-115% except for alanine which was recovered at 79.4%. The findings were reproducible and accurately defined, and the method was found to be suited to routine analysis of amino acid composition in gelatin-based ingredients.


Assuntos
Aminoácidos/análise , Aminoquinolinas/química , Carbamatos/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Gelatina/química , Aminoácidos/química , Animais , Calibragem , Limite de Detecção
6.
Malays J Pathol ; 14(2): 91-4, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1304630

RESUMO

Over a three-year-period, 310 babies with prolonged jaundice admitted to GHKL were studied, to determine the incidence of alpha-1-antitrypsin deficiency as a cause of the problem. Ninety-two babies (29.7%) were found to be alpha-1-antitrypsin deficient. The percentage incidence was found to be highest in Indians (33.3%), followed by Malays (31.9%) and Chinese (26.7%). There was a male preponderance with a M:F ratio of 1.6:1. Most of these babies presented at the hospital at the age of more than two weeks but less than one month. Apart from the problem of prolonged jaundice and alpha-1-antitrypsin deficiency, 2 had associated bleeding problems, 11 associated infections and 3 respiratory problems. Two babies had clinical features of Down's syndrome, 2 had G6PD deficiency and 1 had congenital hypothyroidism. AST, ALT and ALPO4 were high in 20, 26 and 3 babies respectively.


Assuntos
Icterícia Neonatal/epidemiologia , Deficiência de alfa 1-Antitripsina , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Icterícia Neonatal/etiologia , Malásia/epidemiologia , Masculino
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