Simultaneous Determination of Total Vitamins B1, B2, B3, and B6 in Infant Formula and Related Nutritionals by Enzymatic Digestion and LC-MS/MS: Single-Laboratory Validation, First Action 2015.14

Quantification of 10 B vitamins in mouse colon by LC-MS/MS: Application on breast cancer mice treated with doxorubicin

B vitamins play important roles in various physiological processes, including cell metabolism and DNA synthesis. The intestine is critical for the absorption and utilization of B vitamins, but few analytical methods for detecting intestinal B vitamins are currently available. In this study, we developed a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of 10 B vitamins in mouse colon tissue, including thiamin (B1), riboflavin (B2), nicotinic acid (B3), niacinamide (B3-AM), pantothenic acid (B5), pyridoxine (B6), pyridoxal 5'-phosphate (B6-5P), biotin (B7), folic acid (B9), and cyanocobalamin (B12). The method was thoroughly validated following the U.S. Food and Drug Administration (FDA) guidelines and yielded good results in terms of linearity (r² > 0.9928), lower limit of quantification (40-600 ng/g), accuracy (88.9-119.80 %) and precision (relative standard deviation ≤ 19.71 %), recovery (87.95-113.79 %), matrix effect (91.26-113.78 %), and stability (85.65-114.05 %). Furthermore, we applied our method to profile B vitamins in the colons of mice with breast cancer after doxorubicin chemotherapy treatment, which revealed that the doxorubicin treatment led to significant colon damage and accumulation of several B vitamins including B1, B2 and B5. We also confirmed the capability of this method for quantifying B vitamins in other intestinal tissues like the ileum, jejunum, and duodenum. The newly developed method is simple, specific, and useful for targeted profiling of B vitamins in mouse colon, with a potential for future studies on the role of these micronutrients in healthy and diseased states.

Development of a LC-MS/MS method using stable isotope dilution for the quantification of individual B6 vitamers in fruits, vegetables, and cereals

Vitamin B₆ comprises an important set of molecules tightly interwoven with the human amino acid, fatty acid, and carbohydrate metabolism. Analytical methods striving for the quantification of individual B₆ vitamers so far mostly rely on methods based on HPLC in combination with fluorescence detection, but their application encounters multiple difficulties due to the chemical divergence of the single vitamers. The present study describes the development of a method based on LC-MS/MS and stable isotope dilution assay (SIDA) for the simultaneous quantification of five vitamers (PN, PL, PM, PMP, and PNG) of the B₆ group in food samples. [¹³C₃]-PN, [¹³C₃]-PL, and [¹³C₆]-PNG were applied as internal standards for the analysis of PN, PL, and PNG. PM and PMP were quantified via matrix-matched calibration referring to [¹³C₃]-PN. The developed method was validated using starch matrix. The limits of detection and quantification ranged from 0.0028 to 0.02 mg/kg and from 0.0085 to 0.059 mg/kg, respectively, for all analytes. Calculated recoveries varied from 92 to 111%. Intra-injection precisions ranged from 0 to 9%, inter-day precisions from 4 to 10%, and intra-day precisions from 4 to 10%. A total of 14 plant-based food samples including fruits, vegetables, and cereals were examined for their content of vitamin B₆ using the validated method. Furthermore, the first quantitation of PNG without enzymatic steps or divergent internal standards was undertaken utilizing LC-MS/MS and SIDA.

Simultaneous Determination of Total Vitamins B1, B2, B3, and B6 in Infant Formula and Related Nutritionals by Enzymatic Digestion and LC-MS/MS—A Multi-Laboratory Testing Study Final Action: AOAC Method 2015.14

Background/Objective

A multi-laboratory study was completed for AOAC First Action Method 2015.14. Ten laboratories from eight countries participated. Each laboratory analyzed (in duplicate) a placebo and 14 fortified nutritionals. Product matrices analyzed included milk, soy, partially hydrolyzed milk, partially hydrolyzed soy, and elemental-based infant formula powders, milk based infant formula ready-to-feed liquids, adult low-fat powders, and adult high fat and high protein ready-to-drink nutritionals. Data was then compared to standard method performance requirements (SMPR).

Method

Samples were prepared by enzymatic digestion with papain, α-amylase, and phosphatase to hydrolyze protein and complex carbohydrate and to free phosphorylated vitamin forms respectively. Stable-isotope labeled internal standards were incorporated into the sample preparation to correct for variability in both the sample preparation and instrument response. Prepared samples and working standard solutions were injected onto an ultra-high-pressure liquid chromatograph, interfaced to a triple-quadrupole mass spectrometer (MS/MS). Reverse phase gradient chromatography, using mobile phases of methanol and 20 mM ammonium formate in water on a C-18 column, were used for the analysis. The MS/MS was configured to monitor precursor-fragment ion pairs for each analyte and internal standard. Vitamins B1 (thiamine), B2 (riboflavin), B3 (niacin), and B6 (pyridoxine) were quantified by least squares regression using the response ratio of the analyte to its internal standard.

Results/Conclusions

Total vitamins B1, B2, B3, and B6 had average repeatability of 2.3%, 3.9%, 2.7%, and 2.2% RSD, and reproducibility of 8.2%, 6.9%, 6.7%, and 5.8% RSD, respectively. Repeatability and reproducibility SMPR were met for 53/56 and 50/56 fortified-product/analyte pairs analyzed, respectively.

Effect of Diet on the Growth Performance, Feed Conversion, and Nutrient Content of the House Cricket

The house crickets, Acheta domesticus, are sustainable and nutritious future sources of food, due to their nutritional benefits, particular high protein content and potential in solving global malnutrition. Different diets, particularly protein content, can influence the growth and nutritional value of crickets. The aim of this present study was to evaluate the effects of commercial diets and other formulated diets on the nutritional composition and growth parameters of the house crickets, being a major challenge to cricket's farmers in Thailand. Feed conversion ratio were 1.50, 1.50, and 1.51 for fed crickets on a blend of 22% protein and dry pulp pumpkin powder, fed 22% protein plus fresh pumpkin pulp, and fed 22% protein alone, indicated that these groups are high feed convertors and represented the quality of these diets compared to 1.73 and 1.81 for fed crickets on a blend of 22% and 16% protein, and those fed on 16% protein alone. Fed crickets on 22% protein had the highest amount of protein (76%), the lowest (48%) in those fed on 22% protein and fresh pumpkin pulp inclusion. The group on 22% protein diet also had the highest amount of phosphorus, potassium, calcium, and sodium. Fed 22% protein and either dry pulp pumpkin powder or fresh pumpkin pulp condition have shown improvement in vitamin B content. Crickets can effectively be produced on 22% protein diet to improve yield output and several minerals such as phosphorus, potassium, calcium, and sodium. In contrast, the supplementation of 22% protein diet with pumpkin (Cucurbita maxima) will improve vitamin B content.