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1.
Heliyon ; 6(1): e03059, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31909249

RESUMEN

Cyanocobalamin, like other water-soluble vitamins, is susceptible to degradation due to exposure to heat, UV, oxygen and pH. Built on our previous finding, this study aimed to assess the extraction efficiency of cyanocobalamin from dietary supplements. Particularly, cyanocobalamin extraction in a 100 °C water bath was compared with ultrasonic-assisted extraction, with and without the addition of 1 mg/L sorbitol, xylitol and erythritol. Ground defatted samples of supplement tablets were initially treated for 15 min, centrifuged and filtered before quantitative HPLC analysis. Addition of sorbitol and xylitol significantly minimised the thermal degradation during extraction in a 100 °C water bath, as shown in measured cyanocobalamin (~145 µg/tablet) that was higher than the control (100 µg/tablet, p < 0.05). Despite the addition of sugar alcohols, mean cyanocobalamin in ultrasonic extracted samples (~170 µg/tablet) was not significantly different from those without (p > 0.05). Overall, mean cyanocobalamin in sonicated samples was higher than heat-extracted counterparts, suggesting that extraction in a 100 °C water bath was likely to cause thermal degradation. It was possible that ultrasonic-assisted extraction had no effect on cyanocobalamin stability and would lead to a higher extraction efficiency. Therefore, 15 min extraction in an ultrasonic bath can be suggested to be adequate to release cyanocobalamin before its quantitative determination.

2.
Int J Food Sci Nutr ; 70(7): 875-886, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30843745

RESUMEN

Water-soluble vitamin B12 (cobalamin) plays a vital role in normal blood function and neurological functioning. Clinical and subclinical B12 deficiency has been notably reported in vegans, vegetarians, the elderly and metformin-treated diabetics. Currently, the prevalence of cobalamin deficiency among vegans and vegetarians in Australia is lacking; data on dietary intake including supplements and nutritional status are also limited. The increasing multiculturalism of Australia has seen an influx of imported foods, of which some may contain considerable vitamin B12. However, values for such foods are not included in the food composition databases. This review highlights the need to update the food composition database with culturally diverse foods containing vitamin B12. Moreover, the need for assessing dietary intakes and status using the most current best evidence and best practice on nutritional indicators (biochemical and functional biomarkers) to estimate the risk of deficiency and/or depletion is discussed.


Asunto(s)
Veganos , Vegetarianos , Vitamina B 12/sangre , Adolescente , Australia , Niño , Preescolar , Dieta Vegana , Dieta Vegetariana , Femenino , Humanos , Lactante , Masculino , Evaluación Nutricional , Estado Nutricional , Glycine max , Deficiencia de Vitamina B 12
3.
Plant Foods Hum Nutr ; 74(1): 34-39, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30306505

RESUMEN

Lutein is a xanthophyll, a bioactive phytochemical that presents itself as colourful pigments in plants. Australian sweet lupin flour has been incorporated as a food ingredient in wheat bread and pasta to improve their sensory property and nutritional quality. However, the amount of lutein in lupin flour has not yet been determined. This is the first study to quantify naturally occurring lutein in Australian sweet lupin flour after the extraction efficiency was optimised. Several organic solvents (acetone, isopropyl alcohol, ethyl acetate and hexane), the use of an ultrasonic bath or a probe, the need for saponification and addition of ascorbic acid (served as antioxidant) were tested to compare the extraction yield. HPLC was employed to analyse lutein in flour. Lowest lutein (68 µg/100 g) was determined in the hexane extract. Samples extracted using an ultrasonic bath (126-132 µg/100 g) contained higher lutein than those extracted using a probe (84-109 µg/100 g). Saponified samples showed significantly less lutein (30-64 µg/100 g) than their respective non-saponified ones (122-134 µg/100 g). Without added ascorbic acid, lutein that was extracted into isopropyl alcohol was 143 µg/100 g and was higher than those released into acetone (92 µg/100 g). When ascorbic acid was added, measured lutein in the extracts of isopropyl alcohol (155 µg/100 g) and acetone (138 µg/100 g) increased by 8 and 33%, respectively. Our results suggested that the choice of extraction solvents and addition of ascorbic acid was crucial for quantitative analysis of lutein, so that the lutein content in lupin flour can be accurately reported.


Asunto(s)
Antioxidantes/química , Ácido Ascórbico/química , Lupinus/química , Luteína/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Pan , Harina , Humanos , Luteína/análisis , Valor Nutritivo , Fitoquímicos/análisis , Triticum
4.
J Agric Food Chem ; 65(46): 10064-10073, 2017 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-29058428

RESUMEN

This study investigated the effect of germination and fermentation on the composition of carbohydrates in Australian sweet lupin. Specifically, the amount of sugars (sucrose, fructose, and glucose), starch, oligosaccharides (verbascose, stachyose, and raffinose), and dietary fiber were measured in germinated lupin seeds and fermented lupin flour, and compared with those in soy. High performance liquid chromatography coupled with refractive index was employed for quantitation of sugars, starch, and oligosaccharides, and gas chromatography coupled with a flame ionization detector was used for quantitation of simple sugars in total, and soluble, and insoluble dietary fiber. The enzyme activities of α-amylase and α-glucosidase were compared before and after germination or fermentation. The α-amylase activity in germinated lupin increased to  ∼17 nmol/mL/min/0.1 g and in germinated soy∼32; in fermented lupin, the activity increased to ∼52, while in fermented soy it decreased to ∼20. In general, germination or fermentation decreased the oligosaccharide content, and increased the total sugar in samples (p < 0.05). Total oligosaccharides in lupin after uncontrolled germination were reduced by 98% to 6 mg/g, and after controlled germination reduced by 44% to 86 mg/g. Fermentation with yogurt culture lowered the content of total oligosaccharides due to 94% decrease in stachyose. Total oligosaccharides in soy flour prior to fermentation were 180 mg/g and significantly decreased to ∼124 mg/g in fermented soy. Germination did not affect the starch content. There was no significant change in the amounts of total, soluble, and insoluble dietary fiber after germination or fermentation of lupin except for galactose, which was significantly reduced in germinated lupin seeds. Soluble dietary fiber in germinated soy significantly increased. Germination and fermentation are simple and effective techniques to reduce the oligosaccharides while maintaining the composition of dietary fibers.


Asunto(s)
Carbohidratos/química , Harina/análisis , Glycine max/química , Lupinus/química , Semillas/crecimiento & desarrollo , Australia , Fermentación , Germinación , Lupinus/crecimiento & desarrollo , Lupinus/metabolismo , Lupinus/microbiología , Proteínas de Plantas/análisis , Proteínas de Plantas/metabolismo , Semillas/química , Semillas/metabolismo , Semillas/microbiología , Glycine max/crecimiento & desarrollo , Glycine max/metabolismo , Glycine max/microbiología , alfa-Amilasas/análisis , alfa-Amilasas/metabolismo , alfa-Glucosidasas/análisis , alfa-Glucosidasas/metabolismo
5.
Food Chem ; 234: 365-371, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28551248

RESUMEN

This study compares enzymatic treatments to release folic acid (FA) and endogenous 5-methyltetrahydrofolate (5-MTHF) from infant milk formulae with enzyme-free heat extraction. The limits of detection and quantitation of FA were 1.4ng/mL and 3.1ng/mL, respectively; 7.5ng/mL and 16.2ng/mL for 5-MTHF. Absolute mean recoveries were 85% (FA) and 95% (5-MTHF). The RSD of the within-run variability was 6% and the inter-day variability was 8%. Averaged measurements of FA and 5-MTHF in SRM-1849a were within the certified value range. Analysed folate levels in three brands were greater than label values, because of inherently high 5-MTHF occurring in samples. The results indicate that enzyme-free heat treatment prior to UPLC-MS/MS analysis gives better sensitivity and reduces chromatographic interferences for the determination of FA and 5-MTHF in milk formulae than enzymatic treatments. Enzyme-free heat treatment is more compatible with UPLC-MS/MS than folate extraction techniques involving the addition of enzymes to milk.


Asunto(s)
Enzimas/química , Ácido Fólico/análisis , Manipulación de Alimentos/métodos , Calor , Fórmulas Infantiles/análisis , Animales , Espectrometría de Masas en Tándem , Tetrahidrofolatos
6.
Plant Foods Hum Nutr ; 71(1): 90-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26880215

RESUMEN

Apart from being a rich and inexpensive protein source, legumes provide essential vitamins, minerals and dietary fibre. Considering the nutritional benefits, legumes flour can potentially be incorporated in the development of new products. The aim of this study was to investigate whether fermentation affects the protein content, in vitro protein digestibility, trypsin inhibitor activity and the functionality of proteins in faba bean, desi and kabuli chickpea. Australian grown chickpea and faba bean were selected and initially soaked, de-hulled, dried and milled into flour. This was fermented with lyophilised yoghurt cultures in a 30 °C orbital shaker for 16 h. While protein contents in fermented desi and kabuli flour were lower than their raw counterparts (p > 0.05), it was significantly higher in fermented faba bean. A significant increase (9.5%) in in vitro protein digestibility was found in fermented desi. Trypsin inhibitor activity in fermented desi, kabuli and faba bean reduced by 2.7, 1.1 and 4.7%, respectively (p > 0.05). Overall, the in vitro protein digestibility in flour samples increased, while simultaneously reducing the trypsin inhibitor activity. The water absorption capacity of the fermented kabuli flour significantly increased by 11.3%. All fermented flour samples had significantly higher oil absorption capacity than their corresponding raw flour that was likely due to increased insoluble hydrophobic protein. Although, the foaming capacity in all fermented flour samples was significantly lower than their respective raw samples, only fermented desi and faba bean flour showed lower foaming stability (p > 0.05). The present study suggests that fermented legume flour could fulfill the demand for innovative products of higher nutritional value.


Asunto(s)
Cicer/química , Harina , Proteínas de Plantas/análisis , Vicia faba/química , Fabaceae/química , Fermentación , Harina/análisis , Valor Nutritivo , Proteínas de Plantas/metabolismo , Proteolisis , Inhibidores de Tripsina/metabolismo
7.
Int J Food Sci Nutr ; 67(3): 225-31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26903206

RESUMEN

Ready-to-eat breakfast cereals have been voluntarily fortified with folic acid since 1995, with the purpose of reducing the prevalence of neural tube defects in utero. Using data from the recent Australian Health Survey, this study aimed to estimate folate intake from one serving of breakfast cereals (median amount). Various commercial brands were purchased in 2002 (n = 19) and in 2014 (n = 14); folate was determined by microbiological assay and high-pressure liquid chromatography (HPLC). Total folate (µg/100 g) in 2002 and 2014 selections were 144-633 and 147-564, respectively, and mostly comparable to nutrition labels. Folic acid (2014 selection) using HPLC, ranged from 85 to 411 µg/100 g. Intake of 51 g cereals/serving by individuals ≥ 2 years could contribute 75-288 µg dietary folate equivalent. It seems that folic acid intake among children (2-3 years) exceeds the recommended dietary intake, when certain brands of breakfast cereals are consumed. Accordingly, the benefits and potential detrimental effects of the voluntary fortification need to be further explored.


Asunto(s)
Suplementos Dietéticos , Grano Comestible/química , Ácido Fólico/química , Alimentos Fortificados/análisis , Australia , Desayuno , Ácido Fólico/administración & dosificación , Deficiencia de Ácido Fólico/prevención & control , Análisis de los Alimentos , Humanos , Necesidades Nutricionales , Valor Nutritivo
8.
Food Res Int ; 90: 25-32, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29195878

RESUMEN

This study focused on the use of a new system, an alginate|Ɛ-poly-l-lysine|alginate|chitosan microcapsule (APACM), able to immobilize a folate-producing probiotic, Lactococcus lactis ssp. cremoris (LLC), which provides a new approach to the utilization of capsules and probiotics for in situ production of vitamins. LLC is able to produce 95.25±26µg·L-1 of folate, during 10h, and was encapsulated in the APACM. APACM proved its capacity to protect LLC against the harsh conditions of a simulated digestion maintaining a viable concentration of 6logCFU·mL-1of LLC. A nutrients exchange capacity test, was performed using Lactobacillus plantarum UM7, a high lactic acid producer was used here to avoid false negative results. The production and release of 2g·L-1 of lactic acid was achieved through encapsulation of L. plantarum, after 20h. The adhesion of APACM to epithelial cells was also quantified, yielding 38% and 33% of capsules adhered to HT-29 cells and Caco-2 cells, respectively.

9.
Anal Bioanal Chem ; 401(3): 1035-42, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21667347

RESUMEN

An ultra-performance liquid chromatography-tandem mass spectrometry method was developed, optimised and validated for the quantification of synthetic folic acid (FA), also called pteroyl-L: -glutamic acid or vitamin B9 and naturally occurring 5-methyltetrahydrofolate (5-MTHF) found in folate-fortified breads. Optimised sample preparation prior to analysis involved addition of (13)C(5) labelled internal standards, treatments with α-amylase and rat serum, solid-phase extraction using aromatic-selective cartridges and ultra-filtration. Analytes were separated on a Waters ACQUITY HSS T3 column during a 6-min run and analysed by positive ion electrospray selected reaction monitoring MS/MS. Standard calibration curves for the two analytes were linear over the range of 0.018-14 µg FA/g of fresh bread (r(2) = 0.997) and 9.3-900 ng 5-MTHF/g of fresh bread (r(2) = 0.999). The absolute recoveries were 90% and 76% for FA and 5-MTHF, respectively. Intra-day coefficients of variation were 3% for FA and 18% for 5-MTHF. The limit of detection was 9.0 ng/g for FA and 4.3 ng/g for 5-MTHF, determined using pre-extracted tapioca starch as the blank matrix. The assay is rugged, fast, accurate and sensitive, applicable to a variety of food matrices and is capable of the detection and quantification of the naturally occurring low levels of 5-MTHF in wheat breads. The findings of this study revealed that the FA range in Australian fortified breads was 79-110 µg/100 g of fresh bread and suggest that the flour may not have the mandated FA fortification level (200-300 µg/100 g of flour), though this cannot be determined conclusively from experimental bread data alone, as variable baking losses have been documented by other authors.


Asunto(s)
Pan/análisis , Técnicas de Química Analítica/métodos , Cromatografía Líquida de Alta Presión , Ácido Fólico/análisis , Alimentos Fortificados/análisis , Espectrometría de Masas en Tándem , Animales , Australia , Bioensayo/métodos , Límite de Detección , Ratas , Reproducibilidad de los Resultados , Tetrahidrofolatos/análisis , Factores de Tiempo
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