Assessment of thiamine content in some dairy products and rice milk

Thiamine-producing lactic acid bacteria and their potential use in the prevention of neurodegenerative diseases

Thiamine or vitamin B1, an essential micronutrient mainly involved in energy production, has a beneficial impact on the nervous system, and its deficiency can be associated with the development and progression of neurodegenerative diseases. The aim of this work was to select thiamine-producing lactic acid bacteria (LAB) and study their physiological effects using neuron cell cultures. In this study, 23 LAB able to produce thiamine were identified by growth in thiamine-free synthetic medium. Intra- and extracellular thiamine concentrations were determined using a microbiological method and results confirmed by HPLC techniques. A wide variation in vitamin production was found showing that this property was not only species specific but also a strain-dependent trait. Five of these strains were pre-selected for their capacity to produce higher concentrations of thiamine. Only the pre-treatment with the intracellular extract of Lactiplantibacillus (L.) plantarum CRL 1905 increased significantly neuronal survival in N2a cells' model of neurotoxicity (MPP⁺) with thiamine deficiency conditions (amprolium). Furthermore, amprolium-resistant variants of CRL 1905 were isolated by exposition of the strain to increasing concentrations of this toxic thiamine analogue. The variant A9 was able to increase more than 2 times the intracellular thiamine production of the original strain. A9 bacterial extract significantly prevented neuronal cell death and the increase of IL-6. The amprolium-resistant strain A9 showed a modulating and neuroprotective effect in an in vitro model of neurotoxicity constituting a potential bio-strategy to counteract thiamine deficiencies and thus prevent or treat neurodegenerative diseases. KEY POINTS: • LAB can produce thiamine in a species- and strain-dependant manner. • L. plantarum CRL 1905 significantly reduce MPP⁺-induced neurotoxicity in N2a cells. • Amprolium-resistant strain A9 has neuroprotective effect and prevents IL-6 increase.

Cereal grain-based functional beverages: from cereal grain bioactive phytochemicals to beverage processing technologies, health benefits and product features

Increased consumer awareness of health and wellness has promoted a high demand for foods and beverages with functional and therapeutic properties. Cereals, apart from being important staple crops and primary sources of energy and nutrition, are replete with bioactive phytochemicals with health properties. Cereal grains contain a diverse range of bioactive phytochemicals including phenolic compounds, dietary fibers, carotenoids, tocols, phytosterols, γ-oryzanol, and phytic acid and therefore have great potential for processing into functional beverages. Although there are a variety of cereal grain-based beverages produced world-wide, very little scientific and technological attention has been paid to them. In this review, we have discussed cereal grain-based functional beverages based on 3 main categories: cereal grain-based milk alternatives, roasted cereal grain teas, fermented nonalcoholic cereal grain beverages. The processing techniques, health properties and product features of these beverages are elaborated, and the challenges and future perspectives are proposed. As the food market becomes increasingly diverse, cereal grain-based beverages could be a promising new category of health functional beverages in our daily life.

An optimized LC-MS/MS method as a pivotal tool to steer thiamine biofortification strategies in rice

In developing countries, people mainly depend on rice as their primary source of calories. However, the thiamine content of rice is below minimal requirements. Biofortification, via genetic engineering, is a cost-effective strategy to increase thiamine content in rice. We report on the optimization of a matrix-specific method, including extensive optimization of the sample preparation to ensure maximal sensitivity and stability. The LC-MS/MS method was fully validated for the simultaneous quantification of thiamine, its precursors 4-methyl-5-(2-hydroxyethyl) thiazole (HET) and 4-amino-2-methyl-5-hydroxymethylpyrimidine (HMP) and its diphosphate derivative (TDP) in both polished and unpolished rice. Bias was below 9% for all analytes and total imprecision (CV%) was within pre-set acceptance criteria (≤15%) for both QCs and real samples. Thiamine monophosphate (TMP), for which no labeled analogue was available at the time of analysis, was determined without internal standard. Although both accuracy and precision criteria were met (bias and CV < 12%), the determination of TMP was considered semi-quantitatively. Moreover, TMP was found to be only a minor thiamine form (<1% of total thiamine in all lines analyzed, both wild-type and genetically engineered), with measurable levels only present in unpolished rice. Finally, the validity and applicability of the procedure were demonstrated via its successful application on rice lines, genetically engineered to enhance thiamine content. Consequently, this method allows to evaluate the success of biofortification strategies in rice.

Voltammetric detection of vitamin B1 (thiamine) in neutral solution at a glassy carbon electrode via in situ pH modulation

Pretreatment of glassy carbon electrode at an appropriate negative potential provide hydroxide ion which contributes to the in situ pH modulation of the electrode for thiamine detection in neutral solution.

Thiamine Assays-Advances, Challenges, and Caveats

Thiamine (vitamin B1) is essential to the health of all living organisms and deficiency has long been associated with diseases in animals such as fish, birds, alligators, and domesticated ruminant mammals. Thiamine is also implicated in several human diseases including Alzheimer's, diabetes, dementia, depression and, most notably, Wernicke-Korsakoff syndrome and Beriberi disease. Yet, highly sensitive and specific detection of thiamine remains an analytical challenge, as pM to nm levels of thiamine need to be detected in environmental and human samples, respectively, various phosphorylated variants need to be discriminated, and rapid on-site detection would be highly desirable. Furthermore, appropriate sample preparation is mandatory, owing to the complexity of the relevant sample matrices including fish tissues, ocean water, and body fluids. This Review has two objectives. First, it provides a thorough overview of analytical techniques published for thiamine detection over the last 15 years. Second, it describes the principles of analytical approaches that are based on biorecognition and may open up new avenues for rapid and high-throughput thiamine analysis. Most notably, periplasmic binding proteins, ribozymes, and aptamers are of particular interest, as they function as bioaffinity recognition elements that can fill an important assay technology gap, owing to the unavailability of thiamine-specific commercial antibodies. Finally, the authors provide brief evaluations of key outcomes of the major assay concepts and suggest how innovative techniques could help develop sensitive and specific thiamine analytical test systems.

Physicochemical and biochemical parameters in milk of Serbian breastfeeding women

BACKGROUND/AIM

This study was undertaken to determine the changes and relationships between some important milk constituents as well as physical, rheological, and biochemical parameters of milk obtained from Serbian breastfeeding mothers.

MATERIALS AND METHODS

Physicochemical and biochemical parameters and the concentrations of vitamins, uric acid, and minerals were determined during the three periods of lactation covering colostrum, transitional, and mature milk collected from 67 mothers who had a term-pregnancy.

RESULTS

Large interindividual variations regarding many parameters were found between mothers at the same period of lactation, but the average values were mostly in the expected and recommended ranges. For some parameters, our values are quite different in relation to the milk of women from other countries or data reported by other authors.

CONCLUSION

Differences in vitamin and mineral contents and physicochemical and rheological characteristics of milk obtained by Serbian breastfeeding mothers compared to that of mothers from other parts of the world have been found. This paper presents the measured data of some physical parameters of human milk about which there is little information in the literature.