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Spain dominates avocado production in Europe, with the Hass variety being the most prominent. Despite this, Spanish production satisfies less than 10% of the overall avocado demand in Europe. Consequently, the European avocado market heavily relies on imports from overseas, primarily sourced from Peru and Chile. Herein, a comprehensive characterization of the metabolic profile of Hass avocado fruits from Spain, Peru, and Chile, available in the European market throughout the year, was carried out. The determination of relevant substances was performed using high- and low-resolution RP-LC-MS. Remarkable quantitative differences regarding phenolic compounds, amino acids, and nucleosides were observed. Principal component analysis revealed a natural clustering of avocados according to geographical origin. Moreover, a specific metabolic pattern was established for each avocado-producing country using supervised partial least squares discriminant analysis. Spanish fruits exhibited high levels of coumaric acid malonyl-hexose II, coumaric acid hexose II, and ferulic acid hexose II, together with considerably low levels of pantothenic acid and uridine. Chilean avocado fruits presented high concentrations of abscisic acid, uridine, ferulic acid, succinic acid, and tryptophan. Fruits from Peru showed high concentrations of dihydroxybenzoic acid hexose, alongside very low levels of p-coumaric acid, ferulic acid, coumaric acid malonyl-hexose I, and ferulic acid hexose II.

Introduction: The stress which arises as a response to the demands in the academic contexts has been related to alterations on the food consumption patterns and subsequent increase in the risk of developing overweight. Objective: To analyze the association between the level of academic stress and the consumption of high energy foods among graduate students of a public university. Methodology: This is an analytical, observational, and transversal study with a convenient sample of students (n = 15). Inclusion criteria were male or female, 20 to 50 years old, and enrolled in a Masters program. Pregnant women were excluded. The level of academic stress was estimated with the SISCO inventory. Feeding patterns were assessed every 24 hours. Mann-Whitney and Spearman tests were calculated. Results: 73.3% of the students showed a moderate level of academic stress. No differences between the academic stress level and nutrition patterns were found. However, there was a direct relationship between the level of stress and the consumption of vitamin B6 (r = 0.467, p = 0.041) and pantothenic acid (r = 0.517, p = 0.029). Discussion and conclusions: There is controversy regarding the relationship between alimentary habits and academic stress. In this study, no association between academic stress and high energy foods consumption was found; however, a link between this kind of stress and the consumption of vitamin B6 and pantothenic acid was. Further research is suggested on the topic of possible relationships between health professionals under academic stress and their high energy consumption habits., Introdução: O estresse acadêmico gerado em resposta às demandas do campo educacional tem sido relacionado a alterações na alimentação e ao aumento do risco de excesso de peso. Objetivo: Analisar a associação entre nível de estresse acadêmico, consumo de energia e determinados nutrientes em mestrandos de uma universidade pública. Metodologia: Estudo analítico, observacional e transversal. A amostra da população estudantil foi realizada por conveniência (n= 15). Os critérios de inclusão foram homem ou mulher, ter entre 20 e 50 anos e cursar mestrado. Foram excluídas gestantes. O nível de estresse acadêmico foi determinado com o inventário SISCO e a avaliação nutricional com recordatório de 24 horas. As diferenças foram avaliadas pelo teste U de Mann-Whitney e as correlações pelo teste de Spearman. Resultados: 73,3% dos estudantes apresentaram nível moderado de estresse acadêmico. Não foram observadas diferenças entre nível de estresse acadêmico e avaliação nutricional. Existe uma relação direta entre o nível de estresse e o consumo de vitamina B6 (r= 0,467, p = 0,041) e ácido pantotênico (r= 0,517, p = 0,029). Discussão e conclusões: Existe controvérsia sobre a relação entre hábitos alimentares e nível de estresse acadêmico. Não foi encontrada associação entre isso e a ingestão energética, mas foi encontrada associação direta com o consumo de vitamina B6 e ácido pantotênico. É importante considerar a avaliação nutricional por um profissional de saúde devido ao nível de estresse da população avaliada., Introducción: El estrés académico generado como respuesta a las demandas del ámbito educativo se ha relacionado con alteraciones en la alimentación y el incremento del riesgo de exceso de peso. Objetivo: Analizar la asociación entre el nivel de estrés académico, el consumo de energía y ciertos nutrimentos en estudiantes de maestría de una universidad pública. Metodología: Estudio analítico, observacional y transversal. La muestra de la población de los estudiantes se realizó a conveniencia (n = 15). Los criterios de inclusión fueron hombre o mujer, 20 a 50 años y cursando la maestría. Se excluyeron mujeres embarazadas. Se determinó el nivel de estrés académico con el inventario SISCO y la evaluación nutrimental con recordatorio de 24 horas. Las diferencias se evaluaron con prueba de U de Mann-Whitney y correlaciones con prueba de Spearman. Resultados: El 73.3 % de estudiantes presentó un nivel de estrés académico moderado. No se observaron diferencias entre nivel de estrés académico y la evaluación nutrimental. Existe una relación directa entre nivel de estrés con consumo de vitamina B6 (r = 0.467, p = 0.041) y ácido pantoténico (r = 0.517, p = 0.029). Discusión y conclusiones: Existe controversia acerca de la relación entre nivel de estrés académico y hábitos alimentarios. No se encontró una asociación entre el nivel de estrés académico y la ingesta energética, pero sí asociación directa con el consumo de vitamina B6 y ácido pantoténico. Es importante considerar la evaluación nutrimental por parte de un profesional de la salud por el nivel de estrés de la población evaluada.

Plant-parasitic nematodes are a major threat to crop production in all agricultural systems. The scarcity of classical resistance genes highlights a pressing need to find new ways to develop nematode-resistant germplasm. Here, we sequence and assemble a high-quality phased genome of the model cyst nematode Heterodera schachtii to provide a platform for the first system-wide dual analysis of host and parasite gene expression over time, covering all major parasitism stages. Analysis of the hologenome of the plant-nematode infection site identified metabolic pathways that were incomplete in the parasite but complemented by the host. Using a combination of bioinformatic, genetic, and biochemical approaches, we show that a highly atypical completion of vitamin B5 biosynthesis by the parasitic animal, putatively enabled by a horizontal gene transfer from a bacterium, is required for full pathogenicity. Knockout of either plant-encoded or now nematode-encoded steps in the pathway significantly reduces parasitic success. Our experiments establish a reference for cyst nematodes, further our understanding of the evolution of plant-parasitism by nematodes, and show that congruent differential expression of metabolic pathways in the infection hologenome represents a new way to find nematode susceptibility genes. The approach identifies genome-editing-amenable targets for future development of nematode-resistant crops.

Introduction: The AMP-activated protein kinase (AMPK) is a master regulator of energy homeostasis that becomes activated by exercise and binds glycogen, an important energy store required to meet exercise-induced energy demands. Disruption of AMPK-glycogen interactions in mice reduces exercise capacity and impairs whole-body metabolism. However, the mechanisms underlying these phenotypic effects at rest and following exercise are unknown. Furthermore, the plasma metabolite responses to an acute exercise challenge in mice remain largely uncharacterized. Methods : Plasma samples were collected from wild type (WT) and AMPK double knock-in (DKI) mice with disrupted AMPK-glycogen binding at rest and following 30-min submaximal treadmill running. An untargeted metabolomics approach was utilized to determine the breadth of plasma metabolite changes occurring in response to acute exercise and the effects of disrupting AMPK-glycogen binding. Results: Relative to WT mice, DKI mice had reduced maximal running speed (p < 0.0001) concomitant with increased body mass (p < 0.01) and adiposity (p < 0.001). A total of 83 plasma metabolites were identified/annotated, with 17 metabolites significantly different (p < 0.05; FDR < 0.1) in exercised (↑ 6; ↓ 11) versus rested mice, including amino acids, acylcarnitines and steroid hormones. Pantothenic acid was reduced in DKI mice versus WT. Distinct plasma metabolite profiles were observed between the rest and exercise conditions and between WT and DKI mice at rest, while metabolite profiles of both genotypes converged following exercise. These differences in metabolite profiles were primarily explained by exercise-associated increases in acylcarnitines and steroid hormones as well as decreases in amino acids and derivatives following exercise. DKI plasma showed greater decreases in amino acids following exercise versus WT. Conclusion : This is the first study to map mouse plasma metabolomic changes following a bout of acute exercise in W

Dietary intakes of B vitamins and other components involved in one-carbon metabolism, which is necessary for DNA replication, DNA repair, and regulation of gene expression, may be associated with carcinogenesis. We investigated associations between intakes of 11 nutrients (thiamine, riboflavin, niacin, pantothenic acid, vitamin B6, biotin, folate, vitamin B12, methionine, choline, and betaine) and gastric cancer risk. A total of 159 incident gastric cancer cases were identified from the Melbourne Collaborative Cohort Study (N = 41,513) and matched with 159 controls on year of birth, sex, and country of birth using incidence density sampling. Dietary intakes of nutrients were estimated at baseline (1990-1994) using a 121-item food frequency questionnaire. Odds ratios (ORs) and 95% confidence intervals were estimated using conditional logistic regression models adjusting for Helicobacter pylori infection, and other potential confounders. We observed a positive association between intake of niacin and overall gastric cancer risk (OR = 1.33, 95%CI: 1.01-1.75 per SD increment). For thiamine, heterogeneity by subtype (cardia and non-cardia) was found (Phet = 0.05), with weak evidence of an inverse association with cardia cancer risk. Our results do not support increasing intakes of B vitamins or other nutrients involved in one-carbon metabolism to reduce gastric cancer risk in a well-nourished population.Copyright © 2019, © 2019 Taylor & Francis Group, LLC.

Part: B

Several antimalarial drugs exist, but differences between life cycle stages among malaria species pose challenges for developing more effective therapies. To understand the diversity among stages and species, we reconstructed genome-scale metabolic models (GeMMs) of metabolism for five life cycle stages and five species of Plasmodium spanning the blood, transmission, and mosquito stages. The stage-specific models of Plasmodium falciparum uncovered stage-dependent changes in central carbon metabolism and predicted potential targets that could affect several life cycle stages. The species-specific models further highlight differences between experimental animal models and the human-infecting species. Comparisons between human- and rodent-infecting species revealed differences in thiamine (vitamin B1), choline, and pantothenate (vitamin B5) metabolism. Thus, we show that genome-scale analysis of multiple stages and species of Plasmodium can prioritize potential drug targets that could be both anti-malarials and transmission blocking agents, in addition to guiding translation from non-human experimental disease models.

Nutrients involved in one-carbon metabolism may play a role in carcinogenesis through DNA replication, repair and methylation mechanisms. Most studies on urothelial cell carcinoma (UCC) have focused on folate. We sought to examine the association between B-group vitamins and methionine intake and UCC risk, overall and by subtype, and to test whether these associations are different for population subgroups whose nutritional status may be compromised. We followed participants in the Melbourne Collaborative Cohort Study (N = 41,513) for over 20 years and observed 500 UCC cases (89% originating in the bladder; superficial: 279, invasive: 221). Energy-adjusted dietary intakes of B vitamins (B1, B2, B3, B5, B6, B8, B9 and B12) and methionine were estimated from a 121-item food frequency questionnaire administered at baseline (1990-1994), using the residuals method. We used Cox regression models to compute hazard ratios (HRs) of UCC risk per standard deviation (SD) of log-transformed nutrient intakes and 95% confidence intervals, adjusted for potential confounders. We investigated associations by tumor subtype, and tested interactions with sex, country of birth, smoking and alcohol drinking. The risk of UCC appeared not to be associated with intake of B-group vitamins or methionine, and findings were consistent across tumor subtypes and across demographic and lifestyle characteristics of the participants. A potential interaction between vitamin B1 and alcohol drinking was observed (all participants: HR per 1 SD = 0.99 (0.91-1.09), never drinkers: HR = 0.81 (0.69-0.97), p-interaction = 0.02), which needs to be confirmed by other studies. Our findings do not indicate that dietary intake of nutrients involved in one-carbon metabolism are associated with UCC risk.Copyright © 2018 UICC

Survival of the human malaria parasite Plasmodium falciparum is dependent on pantothenate (vitamin B5), a precursor of the fundamental enzyme cofactor coenzyme A. CJ-15,801, an enamide analogue of pantothenate isolated from the fungus Seimatosporium sp. CL28611, was previously shown to inhibit P. falciparum proliferation in vitro by targeting pantothenate utilization. To inform the design of next generation analogues, we set out to synthesize and test a series of synthetic enamide-bearing pantothenate analogues. We demonstrate that conservation of the R-pantoyl moiety and the trans-substituted double bond of CJ-15,801 is important for the selective, on-target antiplasmodial effect, while replacement of the carboxyl group is permitted, and, in one case, favored. Additionally, we show that the antiplasmodial potency of CJ-15,801 analogues that retain the R-pantoyl and trans-substituted enamide moieties correlates with inhibition of P. falciparum pantothenate kinase (PfPanK)-catalyzed pantothenate phosphorylation, implicating the interaction with PfPanK as a key determinant of antiplasmodial activity.

Tato diplomová práce je tvořena dvěma částmi - teoretickou a experimentální. Teoretická část je zaměřena na vitamíny B3, B5 a B9, popis jejich chemických vlastností, výrobu, roli v organismu a výskyt v potravinách a nápojích. Je zde také zmíněno stanovení těchto vitamínů v potravinách a potravinových doplňcích se zaměřením na elektromigrační separační techniky. V experimentální části jsou prezentovány výsledky izotachoforetického stanovení vybraných vitamínů skupiny B v léčivých přípravcích. Nacházejí se zde také výsledky zkoušek stability těchto vitamínů., This diploma thesis is consisted of two parts - theoretical and experimental. The theoretical part is focused on the description of chemical properties, production, role in the organism and presence of vitamins B3, B5 and B9 in food and beverages. Determination of these vitamins in food and food supplements with a focus on electromigration separation techniques is also mentioned. In the experimental part the results of isotachophoretic determination of selected B vitamins in food supplements are presented. There are also mentioned the results of the vitamin stability tests., Fakulta chemicko-technologická, Studentka seznámila členy zkušební komise s obsahem své diplomové práce, poté byla seznámena s posudky vedoucího a oponenta diplomové práce. Studentka odpověděla na otázky oponenta diplomové práce a členů zkušební komise.

The human sodium-dependent multivitamin transporter (hSMVT) is a product of the SLC5A6 gene and mediates biotin, pantothenic acid, and lipoate uptake in a variety of cellular systems. We report here the identification of mutations R94X, a premature termination, and R123L, a dysfunctional amino acid change, both in exon 3 of the SLC5A6 gene in a child using whole genome-scanning. At 15 months of age, the child showed failure to thrive, microcephaly and brain changes on MRI, cerebral palsy and developmental delay, variable immunodeficiency, and severe gastro-esophageal reflux requiring a gastrostomy tube/fundoplication, osteoporosis, and pathologic bone fractures. After identification of the SLC5A6 mutations, he responded clinically to supplemental administration of excess biotin, pantothenic acid, and lipoate with improvement in clinical findings. Functionality of the two mutants was examined by 3H-biotin uptake assay following expression of the mutants in human-derived intestinal HuTu-80 and brain U87 cells. The results showed severe impairment in biotin uptake in cells expressing the mutants compared to those expressing wild-type hSMVT. Live cell confocal imaging of cells expressing the mutants showed the R94X mutant to be poorly tolerated and localized in the cytoplasm, while the R123L mutant was predominantly retained in the endoplasmic reticulum. This is the first reporting of mutations in the SLC5A6 gene in man, and suggests that this gene is important for brain development and a wide variety of clinical functions.

Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies (NDA) derived Dietary Reference Values (DRVs) for pantothenic acid. Pantothenic acid is a water-soluble vitamin, which is a component of coenzyme A (CoA) and acyl-carrier proteins. Pantothenic acid is ubiquitous and deficiency is rare. There are no suitable biomarkers that can be used to derive the requirement for pantothenic acid. Data available on pantothenic acid intakes and health consequences are very limited and cannot be used to derive DRVs for pantothenic acid. As there is insufficient evidence available to derive an Average Requirement and a Population Reference Intake, an Adequate Intake (AI) is proposed. The setting of AIs is based on observed pantothenic acid intakes with a mixed diet and the apparent absence of signs of deficiency in the EU, suggesting that current intake levels are adequate. The AI for adults is set at 5 mg/day. The AI for adults also applies to pregnant women. For lactating women, an AI of 7 mg/day is proposed, to compensate for pantothenic acid losses through breast milk. For infants over six months, an AI of 3 mg/day is proposed by extrapolating from the pantothenic acid intake of exclusively breast-fed infants aged zero to six months, using allometric scaling and reference body weight for each age group, in order to account for the role of pantothenic acid in energy metabolism. The AI for children and adolescents is set at 4 and 5 mg/day, respectively, based on observed intakes in the EU.

Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies (NDA) derived Dietary Reference Values (DRVs) for pantothenic acid. Pantothenic acid is a water-soluble vitamin, which is a component of coenzyme A (CoA) and acyl-carrier proteins. Pantothenic acid is ubiquitous and deficiency is rare. There are no suitable biomarkers that can be used to derive the requirement for pantothenic acid. Data available on pantothenic acid intakes and health consequences are very limited and cannot be used to derive DRVs for pantothenic acid. As there is insufficient evidence available to derive an Average Requirement and a Population Reference Intake, an Adequate Intake (AI) is proposed. The setting of AIs is based on observed pantothenic acid intakes with a mixed diet and the apparent absence of signs of deficiency in the EU, suggesting that current intake levels are adequate. The AI for adults is set at 5 mg/day. The AI for adults also applies to pregnant women. For lactating women, an AI of 7 mg/day is proposed, to compensate for pantothenic acid losses through breast milk. For infants over six months, an AI of 3 mg/day is proposed by extrapolating from the pantothenic acid intake of exclusively breast-fed infants aged zero to six months, using allometric scaling and reference body weight for each age group, in order to account for the role of pantothenic acid in energy metabolism. The AI for children and adolescents is set at 4 and 5 mg/day, respectively, based on observed intakes in the EU.

Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies (NDA) derived Dietary Reference Values (DRVs) for pantothenic acid. Pantothenic acid is a water-soluble vitamin, which is a component of coenzyme A (CoA) and acyl-carrier proteins. Pantothenic acid is ubiquitous and deficiency is rare. There are no suitable biomarkers that can be used to derive the requirement for pantothenic acid. Data available on pantothenic acid intakes and health consequences are very limited and cannot be used to derive DRVs for pantothenic acid. As there is insufficient evidence available to derive an Average Requirement and a Population Reference Intake, an Adequate Intake (AI) is proposed. The setting of AIs is based on observed pantothenic acid intakes with a mixed diet and the apparent absence of signs of deficiency in the EU, suggesting that current intake levels are adequate. The AI for adults is set at 5 mg/day. The AI for adults also applies to pregnant women. For lactating women, an AI of 7 mg/day is proposed, to compensate for pantothenic acid losses through breast milk. For infants over six months, an AI of 3 mg/day is proposed by extrapolating from the pantothenic acid intake of exclusively breast-fed infants aged zero to six months, using allometric scaling and reference body weight for each age group, in order to account for the role of pantothenic acid in energy metabolism. The AI for children and adolescents is set at 4 and 5 mg/day, respectively, based on observed intakes in the EU.

Water-soluble vitamins, in vitro organic matter digestibility (OMD) and dry matter digestibility (DMD) values were determined in various different Czech cheeses. An HPLC method for the simultaneous determination of niacin, pantothenic acid and pyridoxine in cheese was established. Different hydrolysis conditions and enzymes were used to release these vitamins from their complex form. The cheeses contained on average 2.04 mg of niacin, 3.24 mg of pantothenic acid and 2.16 mg of pyridoxine per 100 g of fresh mass. An enzymatic method was applied for the evaluation of OMD and DMD in cheeses. In vitro digestibility values ranged from 83.29% to 99.99% for organic matter (OMD) and 83.33% to 99.87% for dry matter (DMD) after two different enzymatic digestions (pepsin, pancreatin). In addition, cheeses incubated with pepsin plus pancreatin, OMD and DMD were strongly digested (99.04-99.83%, 97.73-99.74%).

The Codex Alimentarius Commission of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) develops food standards, guidelines and related texts for protecting consumer health and ensuring fair trade practices globally. The major part of the world's population lives in more than 160 countries that are members of the Codex Alimentarius. The Codex Standard on Infant Formula was adopted in 1981 based on scientific knowledge available in the 1970s and is currently being revised. As part of this process, the Codex Committee on Nutrition and Foods for Special Dietary Uses asked the ESPGHAN Committee on Nutrition to initiate a consultation process with the international scientific community to provide a proposal on nutrient levels in infant formulae, based on scientific analysis and taking into account existing scientific reports on the subject. ESPGHAN accepted the request and, in collaboration with its sister societies in the Federation of International Societies on Pediatric Gastroenterology, Hepatology and Nutrition, invited highly qualified experts in the area of infant nutrition to form an International Expert Group (IEG) to review the issues raised. The group arrived at recommendations on the compositional requirements for a global infant formula standard which are reported here.

Onderzoek naar de gewichtstoename, drogestofopname en voederconversie in functie van het al dan niet verstrekken van extra L-carnitine bij de opfok van moederloze biggen

Betaine in het voer voor slachtkuikens doet de behoefte aan choline en methionine lager zijn

Toevoeging van de vitamines van het B-complex (5) aan het voer voor varkens in relatie tot de slachtkwaliteit

Dit rapport geeft een overzicht van de totstandkoming van een simultane analysemethode voor thiaminechloride en riboflavine in voedingsmiddelen.

1H, 13C, 15N and 31P NMR was applied to a study of free and protein-bound flavins in order to obtain a better insight into the mechanism by which the function of the flavin coenzyme is "tuned" upon binding to apoflavoproteins. A thorough 13C and 15N investigation of free flavins provided a detailed view on the effects of sterical hindrance and polarization on the structure of oxidized and reduced flavins. Moreover, this study resulted in a semi-empirical basis for the interpretation of NMR data obtained on protein-bound flavins. Remarkable results of the study of free flavins are the fact, that oxidized isoalloxazine is not fully planar in an apolar medium, and that fully reduced isoalloxazine is more planar than believed up till now. Unsubstituted reduced isoalloxazine in water has an almost fully sp 2hybridized N(10) and an N(5) atom which is approximately 70% sp 2hybridized. Upon modification the hybridization of N(5) and N(10) can be modulated rather independently due to steric hindrance. The so-called "butterfly" motion has a low activation barrier, which is probably an important feature for the mentioned tuning mechanism.Flavodoxin from Megasphaeraelsdenii is the protein which is most extensively studied in this thesis. By a 13C relaxation study it was shown that the isoalloxazine ring is strongly immobilized upon binding to apoflavodoxin. Also the phosphate group of FMN is strongly immobilized in the interior of the protein. Moreover, the phosphate group is dianionic in the complex, regardless of the redox state of bound FMN. Based on the NMR data, it was shown that the redox potential for the transition semiquinone/hydroquinone is mainly governed by charge interactions. For the first time a quantification of the redox potential modification by the apoprotein could be established, thereby showing that, contrary to literature reports, the redox potential modulation is not governed by steric effects exerted on the isoalloxazine moiety. Both by 31P NMR and 1H NM

Twee reversed phase HPLC-systemen voor de scheiding van pyridoxine (PN), pyridoxamine (PM) en pyridoxal (PL) werden onderzocht lolaarbij de invloed van een aantal variabelen in kaart gebracht werd. De voor de analyse van vitamine B6 wenselijk geachte hydrolyse van de fosfaatesters werd onderzocht met behulp van standaardoplossingen van de B6 vitaminen. Hierbij werd aandacht geschonken aan een enzymatische hydrolyse en aan een hydrolyse bij verhoogde druk en temperatuur (autoclaaf).

Een mogelijk alternatief voor de microbiologische bepaling van vitamine B6 in levensmiddelen, gebaseerd op HPLC met fluorescentie-detectie, wordt in dit rapport nader onderzocht.

Analyses van vitamine B1 en B2 worden door de afdeling Additieven/Micronutrienten veelvuldig uitgevoerd in zeer diverse produkten. Dit stelt hoge eisen aan de selektiviteit van de gebruikte methoden. Onlangs werd dan ook HPLC geïntroduceerd voor de analyse van vitamine B1 en B2. Op basis van een literatuuronderzoek werd toen gekozen voor een simultane bepaling van vitamine B1 en B2. Inmiddels is echter gebleken dat de enzymen die gebruikt worden voor de hydrolyse van de fosfaatesters niet meer verkrijgbaar zijn. De destijds geraadpleegde literatuur over de HPLC-technieken werd derhalve opnieuw bekeken, waarbij vooral aandacht werd besteed aan de extraktie. Dit onderzoek werd aangevuld met een aantal publikaties over methodieken die geen gebruik maken van HPLC. In dit literatuuroverzicht wordt ingegaan op HPLC-technieken voor vitamine B1 en B2, het accent zal liggen op de extraktie procedures.

The present synthetic program on antagonists of pantothenic acid was based on the demonstrated antimalarial activity of chlorophenylpantoylsulfone (SN 14622, WR 29,224) in avian malaria from World War II program. During the three years of our work we have prepared and submitted for evaluation one hundred and eight compounds. Unfortunately, SN 14622 is completely inactive in the present WRAIR screens in mice, chicks and mosquitoes. It appears that the nonproductibility of the activity of SN 14622 in the present chick screen is due to the different test procedure being used. A few of our compounds were tested in Dr. Trager's in vitro screen and of these WR 54036 has been selected for advanced screening in the monkey. Three other compounds, WR 61467, AE 96096 and AF 14571 (derivatives of sulfonamides) have been found to be active in the Rane screen in mice at 160, 40, and 160 mg/kg respectively.

The investigation originated in an attempt to determine why deficiencies of vitamin B6, biotin, and pantothenic acid markedly reduce the steady state amino acid accumulation level in Lactobacillus plantarum and Streptococcus faecalis despite a normal initial transport rate. In the course of these studies a large number of related investigations have been carried out and are summarized. These include: Studies on enhanced RNA degradation in vitamin B6-deficient cells; A demonstration that intracellular amino acid pools in bacteria are osmotically active; An in vitro study of the biosynthesis of a dipeptide, D-alanylcysteine; A demonstration that a pantothenic acid deficiency renders L. plantarum unusually sensitive to lysozyme digestion; A quantitative description of the lipid constituents of S. faecalis and L. plantarum; An investigation of the biochemical basis of a marked lytic tendency in S. faecalis grown in biotin-deficient media; Electron microscopic studies; A demonstration of actinomycin D inhibition of amino acid transport; and A description of the transport systems which function for aminophosphonic acid uptake in bacteria. (Author)

The study was designed to develop a method for sterilizing vitamin-fortified commercial diets for feeding germ-free and defined-flora rodents that would (a) require less time and (b) not destroy vitamins. Feed contaminated with Bacillus stearothermophilus and B. subtilis was sterilized in high-temperature, high-prevacuum autoclave and assayed for vitamin A, thiamine, and pantothenic acid. It was found that: (1) The use of high-temperature, high-prevacuum autoclaves makes possible a reduction in the time required to sterilize autoclavable, commercial diets. Previous methods have required temperatures ranging from 225 to 255F for 25 min to 1 hr to sterilize pelleted diets adequately. The procedure described in this report requires an autoclave cycle of only 12 min and a temperature of 275F. The sterilized feed can be removed from the autoclave 18 min after initiation of the cycle. (2) Sterilization by the method described reduces the loss of vitamin A, thiamine, and pantothenic acid. This study also showed that pelleted rodent diets in quantities of at least 50 lb can be sterilized in open bulk containers. (Author)

A study of 160 patients with psoriasis revealed a reduction in the content of vitamin A in patients with various forms of psoriasis. During treatment with group B vitamins the best therapeutic effect was observed with vitamins B5 and B15. An increase of vitamin A in the blood was noted during treatment with vitamins B2 and pellagra preventive factor, whereas vitamins B1, B5, B6, B9, B12 and B15 caused a decline of the vitamin A level in the blood. During treatment of psoriatic patients with pyrogenal the content of vitamin A in the blood increased, while methotrexate therapy caused it to decrease. Vitamin A appears to be effective in the treatment of various forms of psoriasis both alone and in combination with methotrexate and vitamins B1, B5, B6, B9, B12 and B15.