Poucos trabalhos foram publicados envolvendo a biossíntese do AA em plantas desde sua descoberta em 1928. O mecanismo de biossíntese era um mistério até 1998 quando Wheeler, Jones e Smirnoff demonstraram que a L-galactose é um precursor chave desta importante vitamina. Utilizando-se açúcares marcados e frios pudemos confirmar o mecanismo Smirnoff-Wheeler de biossíntese do AA. Neste trabalho nós apresentamos os resultados alcançados usando alguns supostos precursores e alguns frutos como o morango, a goiaba e o mamão papaya, e alguns legumes como o brócolis, alguns deles ricos em AA. As técnicas de HPLC e espectrofometria UVNIS foram utilizadas na determinação do AA. Os vegetais foram mantidos em soluções dos precursores frios por 24 horas e então analisados quanto ao teor de AA. Os resultados do uso de compostos marcados foi analisado utilizando-se a cintilografia líquida (LSC). Os açúcares extraídos do brócolis, do mamão papaya e da goiaba que foram infiltrados com D-[U-14C] manose, L-[1-14C] galactose e D-[U-14C] glucose-1-P mostraram diferentes padrões de distribuição entre os açúcares envolvidos no mecanismo Smirnoff-Wheeler de biossíntese do AA. Em folhas de goiabeira encontramos altos teores de ácido desidroascórbico e pequena quantidade de AA, diferentemente do conteúdo de AA nos frutos. Nossos resultados confirmaram que a L-galactono-1 ,4-lactona é um precursor bastante eficiente do AA em frutos e proveram algumas evidências do envolvimento da 0- manose no mecanismo de biossíntese do AA em plantas. / Since the first isolation of the Ascorbic Acid (AA) in 1928, a few papers have been published leading with the determination the AA biosynthetic pathway in plants. This pathway was a mystery until recently when in 1998 Wheeler, Jones and Smirnoff demonstrated that L-galactose is a key precursor of this important vitamin. Using radiolabeled and non-radiolabeled sugars we were capable of giving support to the Smirnoff-Wheeler pathway of AA biosynthesis. In this work we present the results reached using some putative precursors and some fruits and vegetables as strawberry, guava, papaya and broccoli some of them very rich in AA. The techniques used for the AA analysis included UVNIS spectrophotometry and HPLC methods. The fruits and vegetables were maintained in the solution of the non-radiolabeled precursors for 24 hours and then analyzed for the AA content. The results of the use of radiolabeled precursors were analyzed using liquid scintillation (LSC). The sugars extracted from broccoli , papaya and guava, that were supplied with D-[U-14C] mannose, L-[1-14C] galactose and D-[U-14C] glucose-1-P dipotassium salt were analyzed using HPLC amperometric method and LSC showed different pattern of distribution between the sugars involved in the Smirnoff-Wheeler AA biosynthesis pathway. In guava leaves we found a high content of dehydroascorbic acid and low amount of AA, unlikely of the content of AA in the fruit. Our results confirmed that L -galactono-1 ,4-lactone is a very effective precursor of AA in fruits and provided some evidence of the involvement of D-mannose in AA biosynthesis in plants.

O pólen além de ser a principal fonte de alimento não líquido, para as abelhas, tem sido utilizado como um suplemento da dieta humana. Apesar de muitos autores afirmarem que os produtos apícolas são ricos em nutrientes, pouco se sabe sobre a composição do pólen apícola especialmente em relação à presença das vitaminas do complexo B. De forma original este estudo teve por objetivo avaliar a estabilidade das vitaminas do complexo B (B1, B2, B6 e PP) incluindo seus vitâmeros, durante o período de um ano de estocagem, em amostras de pólen apícola desidratado. Verificou-se também o efeito do processamento sobre o conteúdo dessas vitaminas além da possível influência dos tipos polínicos sobre a composição centesimal e conteúdo vitamínico. Foram analisadas concentrações das vitaminas no tempo zero e após 4, 8 e 12 meses, estocadas sob três condições distintas: em temperatura ambiente (com e sem exposição à luz) e em freezer. As vitaminas, após a extração simultânea, foram quantificadas por CLAE, com detecção por fluorescência. Todas as vitaminas propostas foram encontradas nas amostras analisadas e o processo de desidratação não interferiu no conteúdo das mesmas (p<0,05). As variações foram (base seca): 0,59 a 1,09 mg/100g para vitamina B1; 1,73 a 2,56 mg/100g para a vitamina B2; 6,43 a 15,34 mg/100g para a vitamina PP e 0,33 a 0,68 mg/100g para a vitamina B6 . Todas as amostras foram classificadas como pólen heterofloral, em função da grande variabilidade dos tipos polínicos presentes. Após um ano de estocagem pode-se afirmar que a concentração da vitamina B1 se manteve constante enquanto que para as demais vitaminas o decaimento da concentração foi dependente do tempo de armazenamento e não da condição de estocagem das amostras (p<0,05). Todas as amostras foram consideradas fonte da vitamina B2. Foi possível explicar matematicamente, através de equações de regressão linear oriundas da análise multivariada, a influência do tempo de armazenamento nas concentrações das vitaminas B6 e PP, com explicabilidade de 76 e 60% respectivamente. / Pollen is the main source of non liquid food for bees and it has been used as a supplement for human diet. Although many authors cited that bee products are rich in nutrients, it is known a little about the composition of bee pollen and, in particular, the presence of the B vitamin complex in this product. This original study has the objective of evaluate the stability of B complex vitamins (B1, B2, B6 and PP), including its vitamers for a period of one year of storage in dried samples of bee pollen. It was also analyzed the effect of processing on vitamin content and the possible influence of polinic types on proximate composition and vitamin content. Samples were analyzed at time zero, after 4, 8 and 12 months. They were storaged under three different conditions: room temperature (with and without exposure to light) and freezer. The vitamins were quantified by HPLC with fluorescence detection after simultaneous extraction. All proposed vitamins were found in the analyzed samples and the dehydration process did not interfere in vitamin content (p<0.05). The variations were (dry basis): 0.59 to 1.09 mg/100g for vitamin B1; 1.73 to 2.56 mg/100g for vitamin B2; 6.43 to 15.34 mg/100g for vitamin PP and 0.33 to 0.68 mg/100g for vitamin B6. All samples were classified as heterofloral pollen, according to the big variability of polinic types. After one year of storage, it can be stated that vitamin B1 concentration remained constant, while for the other vitamins, the concentration loose was dependent on time and not on the storage condition (p<0.05). All samples were considered Vitamin B2 source. It was possible to explain mathematically, through linear regression equations of multivariate analysis, the influence of storage time in the concentrations of vitamin B6 and PP, they were explained as 76 and 60% respectively.

Entende-se por pólen apícola o resultado da aglutinação do pólen das flores, efetuado pelas abelhas operárias, mediante néctar e substâncias salivares, o qual é recolhido no ingresso da colmeia. A literatura descreve que esse alimento contém proteínas, carboidratos, lipídeos, vitaminas e minerais. De acordo com estudo prévio, amostras de pólen apícola in natura e desidratado, da cidade de Pariquera-Açu (São Paulo), apresentaram teores significativos de vitamina B1(tiamina) e B2 (riboflavina), além da presença dos vitâmeros da vitamina B3 (ácido nicotínico e nicotinamida) e B6 (piridoxal, piridoxol e piridoxamina) em sua composição o que foi associado à flora local explorada pelas abelhas. A região Sul do Brasil possui clima, relevo e vegetação diferenciados de outras regiões, necessitando-se assim da verificação do potencial vitamínico deste produto local. Destaca-se, ainda, o fato de que nesta região encontra-se um dos dois maiores produtores nacionais de pólen apícola (estado de Santa Catarina). O presente trabalho teve como objetivo principal quantificar os teores das vitaminas do complexo B: vitaminas B1 e B2, assim como os vitâmeros das vitaminas B3 e B6. Foram coletados 28 lotes de pólen apícola desidratado de diferentes localidades da região Sul durante o período de agosto de 2011 a dezembro de 2012 que posteriormente foram armazenados, a -18 °C até o momento das análises. As vitaminas do complexo B foram analisadas por cromatografia liquida de alta eficiência (CLAE) na matriz pólen apícola desidratado e os resultados foram expressos em base seca. Entre as amostras analisadas foram verificados teores de vitamina B1 variando entre 0,46 e 1,83 mg / 100 g de pólen apícola; vitamina B2 de 0,40 à 1,86 mg / 100 g e quanto à vitamina B6 apenas os vitâmeros piridoxal e piridoxamina puderam ser quantificados em todos os lotes analisados. O piridoxal teve variação entre as amostras de 0,42 à 6,70 mg / 100 g e a piridoxamina de 0,26 à 0,95 mg / 100g. Em relação à vitamina B3, o vitâmero ácido nicotínico apresentou-se nos diferentes lotes variando de 0,68 à 3,93 mg / 100 g e a nicotinamida de 0,27 à 5,54 mg / 100 g de produto. Tomando-se como porção sugerida para consumo diário 25 g de pólen apícola, verificou-se que num total de 28 amostras, 15 foram consideradas fontes e 2 como ricas em tiamina; 19 lotes foram fontes e 3 ricos em riboflavina, e; 2 lotes foram fontes e 26 ricos em piridoxina segundo à Ingestão Diária Recomendada (IDR) para adultos como disponibilizado na Resolução de Diretoria Colegiada (RDC) nº. 269, de 22 de setembro de 2005. / Bee pollen is understood to be the result of agglutination of pollen from flowers, made by worker bees, and nectar through salivary substances, which is collected at the hive entrance. The literature describes that this product contains proteins, carbohydrates, lipids, vitamins, minerals. Previous study with fresh and dehydrated bee pollen, from the city of Pariquera-Açu (São Paulo) showed significant levels of vitamin B1 (thiamine), B2 (riboflavin), presence of B3 (nicotinic acid and nicotinamide) and B6 (pyridoxal, pyridoxamine, piridoxol) vitamins vitamers in its composition which was associated with the local flora explored by bees. Southern Brazil has a differentiated climate, topography and vegetation from other regions, thus requiring verification of vitamin potential of this local product. Also stands out the fact that this region is one of the two largest national producers of bee pollen (Santa Catarina state). This study aimed to quantify the levels of B complex vitamins: vitamins B1, B2, as well as the vitamers of vitamins B3 and B6. Thus, it was collected 28 batches of dehydrated bee pollen from different locations in the South during the period from August 2011 to December 2012. Samples were obtained and subsequently stored at -18 ° C until the analysis time. B vitamins were analyzed by high performance liquid chromatography (HPLC) in bee pollen dehydrated matrix and results were expressed on a dry basis. Among the samples it levels of vitamin B1 varied from 0.46 to 1.83 mg / 100 g; vitamin B2 from 0.40 to 1.86 mg / 100 g; and for vitamin B6, only the pyridoxal and pyridoxamine vitamers could be quantified in all analyzed batches. The pyridoxal had variation between samples from 0.42 to 6,70 mg / 100 g and pyridoxamine from 0.26 to 0.95 mg / 100g. Taking 25 g of bee pollen as suggested for daily intake portion, it was found in a total of 28 samples that 15 were considered sources and 2 rich in thiamine; 19 lots were sources and 3 rich in riboflavin, and; 2 lots were sources and 26 rich in pyridoxine in relation to the Reference Daily Intake (RDI) for adults as provided in Resolução de Diretoria Colegiada (RDC) nº 269, de setembro de 2005.

For centuries, researchers have attempted to devise the ideal parenteral nutritional product readily amenable to physiological requirements. Hyperalimentation, intravenous alimentation, parenteral alimentation, parenteral feeding, and total parenteral nutrition are synonyms which refer to a method of complete intravenous nutrition reserved for patients demonstrating negative nitrogen balance. The nutrient solution appeared to accommodate levels of potassium phosphate, calcium gluconate, and magnesium sulfate well in excess of “usual” therapeutic concentrations. Similarly, commonly employed vitamin supplements and insulin were examined in combination with the hyperalimentation solution and failed to demonstrate signs of physical incompatibility. However, instrumental analysis, i.e., U.V. spectroscopy and thin-layer chromatography, suggested, in fact, there may have been chemical interaction of Solu B Forte and MVI once admixed with the amino acids/dextrose solution. Yet, results of thin-layer chromatography did not appear to substantiate chemical interaction between MVI and the amino acids solution. The investigator contends further study of multiple vitamin infusion stability be completed before definite conclusions are formulated regarding their compatibility in this nutritional infusate.

This diploma thesis was focused on biologically active compounds determination. 26 samples of honey, one sample of propolis and one sample of royal jelly were analyzed. Honey were harvested in year 2006 and 2007 and bought in retail chain, special shops and directly from bee-keeper. Samples were analyzed by titration, spectrofotometry, LC/MS and RP-HPLC methods. The study was focused on analysis of antioxidants. Followed groups of antioxidants were determined: flavonoids, catechins, carotenoids, vitamins E, C, A. Authenticity of quality was determined by hydroxymethylfurfural analysis. Average values of total antioxidant capacity ranged (12.75-137.49) mmol .100 g-1. Average values of total phenolic ranged (8.51-61.34) mg .100 g-1 and average values of total flavonoids ranged (0.75-6.04) mg .100 g-1. Honey samples contained (41.83-585.10) g .100 g-1 of rutin, (9.30-313.40) g .100 g-1 of myricetin, (6.5-171.90) g .100 g-1 of luteolin, (3.19-436.37) g .100 g-1 of quercetin, (2.10-242.66) g .100 g-1 of apigenin, (0.15-105.12) g .100 g-1 of caempferol and (0.07-17.52) mg .100 g-1 of naringenin. From group of catechins there were measured (5.98-310) g .100 g-1 of catechin, (17.77-486.29) g .100 g-1 of epicatechin, (0.18-64.90) g .100 g-1 of catechin gallate and (0.59-140.56) g .100 g-1 of epicatechin gallate. From lipophilic compounds the most abundant in honey samples was tocopherol, its value ranged (29.20-8531.17) g .100 g-1. Content of ascorbic acid ranged (0.65-4.65) mg .100 g-1. Content of hydroxymethyl.furfural. ranged (0.26-4.06) mg .100 g-1. By LC/MS method luteolin, naringenin, protocatechin acid, coffee acid and p-cumaric acid in honeydew were detected and, furthermore, kyanidin and pinocembrin in floral honey were found. Mono-floral honey contained biologically active compounds the most, imperceptibly less contained multi-floral honey and honeydew honey. Acacia honey contained the lowest amount of biologically active compounds.

This master‘s thesis deals with quantification of vitamin B6 in beverages, food supplements and raw materials in food industry. The literature retrieval part summarizes general information about vitamines, vitamine B6, nicotine acid and vitamine B1. Further on in this part there is described principle of high pressure liquid chromatography and quantification of individual vitamines. In the experimental there are listed used tools, apparatus and chemicals. There is described preparation of idividual samples of food supplements, energy drinks, multivitamine drinks, beers and brewer’s malts. This chapter also contains information about chromatographic separatory systems Shimadzu and SpectraSystem. The quantification was performed by high pressure liquid chromatography on a reverse phase with gradient elution and two ways of detection, fluorescent and spectrofotmetric. The result of experimental activities and vitamine content in analysed samples are presented in the next chapter. In the final contains summarization of results obtained in experimental part. The maser’s thesis was measured in the laboratory of Institute of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology.

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This chapter focuses on the role of antioxidant vitamins in protecting the gastrointestinal (GI) tract from oxidative stress. A systems medicine approach is used since it alone is sufficiently comprehensive to capture the broad range of relevant complexities and interrelationships relevant to GI protection. Systems medicine utilizes and integrates the vast amount of information gained from genomics and metagenomics, as well as environmental factors, and applies this information to better patient care. A major goal of system medicine is to develop paradigms to treat or slow the progression of chronic diseases, that is, disease prevention. GI disorders are quintessential examples of chronic inflammation with its attendant oxidative stress. Genomics and metagenomics have provided great insight into the underlying molecular mechanisms for GI disorders and will eventually help define individualized diets to minimize chronic inflammation. While the role of antioxidant nutrients and micronutrients is promising, there is a need for large-scale well-designed clinical trials supported by studies using animal models.

Thesis (Ph.D.(Microbiology)) -- University of Limpopo, 2022 / Traditional sorghum juice is produced in many African countries for human consumption. The juice is very rich in calories, B-group vitamins including thiamine, folic acid, riboflavin, nicotinic acid, and essential amino acids such as lysine. Low earning income women at village level produce sorghum juice for home consumption and sale. The short shelf life (2 to 3 days) of sorghum juice is a major problem for both the brewers and consumers of this drink. The aim of the study was to use 12 Combretum plants to improve the microbiological quality and shelf life of sorghum juice. Fresh stems and leaves of C. caffrum, C. vendae, C. erythrophyllum, C. elaegnoides, C. apiculatum, C. imberbe, C. adenogdium, C. padoides, C. bracteosum, C. kraussii, C. mkuzense and C. zeyherii were collected at Nelspruit, National Botanical Gardens, Mpumalanga, South Africa. Voucher specimens and tree labels were used to verify the identity of the plants. The stems and bark collected were cut into pieces and air dried for 30 days. When dried, the plant material was ground to a fine powder and stored in paper bags at room temperature. The wood was burnt in an open fire; fuel was not used to minimise contamination. The qualitative phytochemical composition of both the leaves and stems of Combretum plants analysed in this study revealed the presence of saponins, tannins, terpenoids, steroids, cardiac glycosides and flavonoids. The following phytoconstituents were lost in the ashes; tannins with the exception of C. mkuzense and C. padoides; cardiac glycosides and flavonoids. The quantitative phytochemical analyses revealed that both the leaves, stems and some ashes such as C. apiculatum and C. vendae contained appreciable levels of phenolic compounds, tannins and flavonoids. Quantitative analysis of antioxidant activity, the 2, 2, diphenyl-1-picrylhydrazyl (DPPH) assay was used as a screen test for the radical scavenging ability of the compounds present in the different 36 70% acetone extracts. DPPH screening method indicated great scavenging activity with the 70% acetone leaf extracts of C. kraussii, C. zeyherii and C. mkuzense. The leaf and stem extracts showed substantial great antioxidant activity in a concentration-dependent manner. There was a significant decrease in the antioxidant activity in the ashes (p=001), when compared to both the leaves and the stems. The proximate and nutritional analysis of the 70% acetone extracts were performed by AOAC and ICPE protocols, respectively. The results indicated that all the extracts had substantial amounts of ash, moisture, protein and energy. Mineral content of the plant parts was analysed as well, calcium had the highest concentration, while zinc was lowest in concentration. The mineral content decreased significantly in the stems (p ≤ 0.05) when compared to the leaves. There was a further decrease in mineral content with regard to the ashes with the exception of calcium. Based on these findings, the leaves and ashes of C. adenogonium and C. apiculatum could provide a good source of calcium in the diet, while C. adenogonium, C. bracteosum and C. apiculatum had high levels of sodium. A serial micro-dilution assay was used to determine the minimum inhibitory concentration (MIC) values for 70% plant extracts using tetrazolium violet reduction as an indicator of growth. Two Gram-positive (Stapylococcus aureus ATCC 29213 and Enterobacter faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853) bacterial strains were used in this study. The leaves had good antibacterial properties with the lowest MIC value being 0.04 mg/ml against E. coli and S. aureus. E. faecalis was found to be resistant against all the leaves with the exception of C. imberbe. The stem extracts of Combretum spp. tested in the study showed antimicrobial properties with the lowest MIC value being 0.04 mg/ml against E. coli shown by C. bracteosum. However, E. faecalis was resistant against all the 12 plants tested. All the test microorganisms showed resistance to the ashes, with the exception of S. aureus, which was found to be susceptible to 75% of the test ash extracts with the lowest MIC value of 0.16 mg/ml. Cytotoxicity and anticancer activity of the acetone extracts of the 12 Combretum plants were evaluated using tetrazolium-based colorimetric assay (MTT assay) on A549 lung carcinoma cells. The assays revealed that 50% of the leaf extracts of tested plants showed cytotoxicity and cell proliferation inhibition in A549 lung carcinoma cells in a concentration-dependent manner. The A549 cells were more sensitive to the following plants: C. elaegnoides, C. erythrophyllum C. imberbe, C. kraussii and C. mkuzense. The following stems extract, C. adenogdium and C. caffrum did not have any anticancer activity, whereas C. apiculatum and C. bracteosum were only able to reduce cell viability to less than 60%. C. mkuzense, C. padoides, C. vendae and C. zeyherii acted in a concentration-depended manner with the greatest activity seen at the highest concentration (1000 µg/ml). The plants had activity at concentrations between 31.25 and 1000 µg/ml allowing only 20% and 50%, respectively, of the cells to remain viable. Ashes from C. mkuzense showed good anti-cancer activity at the highest concentration (1000 µg/ml) reducing cell viability to around 10%. Enterobacteriaceae, total coliform, S. aureus, B. cereus, E. coli and lactic acid bacteria viability were studied during the four weeks storage period of prepared sorghum juices. Juice samples were collected after preparation; the samples were serially diluted using peptone water. Tempo instrument (Biomereiux) was used to enumerate total coliform, total aerobic count, E. coli, S. aureus, lactic acid bacteria, enteric bacteria, yeast and mould using the most probable number following the manufacturers instruction. C. mkuzense and C. padoides plants were able to inhibit the growth of B. cereus, lactic acid bacteria and S. aureus during the first three weeks of storage. E. coli was not present throughout the four weeks storage time. Vitek 2 Compact (Biomereiux) was used for the characterisation and identification of the dominant bacterial isolates using biochemical reactions. The isolates were characterised by morphological differences. Sixty five percent of the isolates were the Enterobacter genus that are commonly found in soil, water, and sewage. The nutritional composition and sensory properties of the prepared sorghum juices treated with Combretum plants were investigated. All the juices had appreciable amounts of protein, ash and energy. Sorghum juice treated with ashes of C. caffrum, C. erythrophyllum and C. kraussii had the highest levels of proteins when compared with other treated sorghum juices. The sorghum juices prepared in the study had varying levels of trace element or minerals with potassium -(3, 55 – 104 mg/l) and calcium (3.2-148 mg/l). Similarly, cobalt (-1.22), coppr (-0.99), iron(-0.962), magnesium (0.004), sodium (-0.145), nickel (-2.7)) and zinc (-1.2)are present in very low amounts. The juices treated with ashes had relatively higher levels of calcium, potassium, magnesium and sodium. Sorghum juices treated with the ashes had better sensory and organoleptic properties when compared with those treated with the leaves. The juices treated with the ashes of C. caffrum and C. bracteseum were more accepted by most of the panellist when compared with other treated juices. Overall, this study presents valuable information on the phytochemical composition, nutritional composition and antioxidant properties of some Combretum species in South Africa. It recommended its use as food and in pharmaceutical preparations for the local industries. In addition, Combretum plants showing the effects tested in this study may be explored further for development into drugs. functional food as food preservatives and nutraceutical applications, beside their traditional use / University of Limpopo and Foodbev SETA

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