Vitamin analysis of five planktonic microalgae and one macroalga

Vitamin analysis was carried out on five microalgae used in aquaculture:Tetraselmis suecica, Isochrysis galbana, Pavlova lutheri, Skeletonema costatum andChaetoceros calcitrans and one macroalga,Sargassum muticum, which is invasive on the Atlantic shores of France. Both liposoluble (provitamin A, E, K) and hydrosoluble (B₁, B₂, B₆, B₁₂, C, PP) vitamins were quantified. For most of them, greater amounts were obtained in the algal products than in the usual sources. On a dry weight basis,Tetraselmis suecica contained 4280 μg g^?1 provitamin A and 6323 μg g^?1 vitamin E,Pavlova lutheri 1162 μg g^?1 vitamin B₁₂ and 837 μg g^?1 vitamin C,Isochrysis galbana 2690 μg g^?1 vitamin PP and 183 μg g^?1 vitamin B₆, andSkeletonema costatum 710 μg g^?1 vitamin B₁.     

An Improved Medium for the Photoautotrophic Culture of Cytisus scoparius Link Cells

The photoautotrophic culture medium for Cytisus scoparius Link cells was improved. Linsmaier and Skoog medium was modified by adding a 4-fold concentration of phosphate and lowering the auxin concentration (a-naphthaleneacetic acid 10^?6M). Concentrations of all the inorganic elements except phosphate in the original basal medium were adequate for the photoautotrophic growth of Cytisus cells. A high concentration of cytokinin compensated for the inhibition of growth caused by a high concentration of auxin.     

Vitamin losses during frozen storage of Liza aurata (Risso, 1810), Cyprinus carpio L. 1758, Clupeonella cultriventris caspia (Nordmann, 1840), Rutilus frisii kutum (Kamenskii, 1901) and Sander lucioperca (L., 1758)

The objective of this study was to determine the fat and water‐soluble vitamins contents (A, E, D, K, B₁, B₂, B₆, B₁₂, niacin, biotin, ascorbic, folic and pantethonic acids; in mg kg^?1 fresh weight) lost during frozen storage (?24°C) in time intervals of 0, 1, 2, 3 and 4 months. Studied species included: Liza aurata (golden grey mullet), Cyprinus carpio (common carp), Clupeonella cultriventris caspia (common kilka or sprat), Rutilus frisii kutum (Caspian kutum) and Sander lucioperca (pike perch). Results showed that A, D and K vitamin losses occurred in all samples during storage, but no statistically significant differences were observed. Vitamin E losses under frozen conditions were significant in common kilka, Caspian kutum and pike perch, however, not in golden grey mullet or common carp. A decrease in vitamin C was significant in all fish species, but there were no significant decreases in other water‐soluble vitamins (B₁, B₂, B₆, B₁₂, niacin, folic acid, pantothenic acid, biotin).     

GROWTH OF VITAMIN B12-LIMITED CULTURES: THALASSIOSIRA PSEUDONANA,MONOCHRYSIS LUTHERI,AND ISOCHRYSIS GALBANA1,2

The growth rates of 3 species of phytoplankton were found to be dependent on the vitamin B₁₂ concentrations in the media. In batch cultures, the vitamin B₁₂ half-saturation constants and standard errors were 0.39 ± 0.042 μμg/ml for Thalassiosira pseudonana (clone 3H), 1.69 ± 0.24 μμg/ml for Isochrysis galbana, and 2.77 ± 1.65 μμg/ml for Monochrysis lutheri. A chemostat was used to grow T. pseudonana with vitamin B₁₂ as the controlling factor. In the chemostat the yield and standard deviation, 102 ± 21 × 10⁴ cells/μμg vitamin B₁₂, was the same as in the batch culture, 126 ± 13 ± 10⁴ cells/μμg. The chemostat half-saturation constant, 0.26 ± 0.068 μμg/ml vitamin B₁₂, and maximum growth rate were in agreement with those obtained in batch cultures. Vitamin concentrations for maximum growth, rates were greater than those calculated necessary from yield data to give observed population densities similar to those in natural waters. In the sea the effect of vitamin B₁₂ concentration on growth rates may be complicated by low concentrations of other nutrients or the presence of inhibitors.     

The effect of dietary vitamin B6 on tissue fat contents and lipid composition in livers and gills of Atlantic salmon (Salmo salar)

Atlantic salmon (9 g) were fed a basal experimental diet supplemented with vitamin B₆ at 0, 5 and 10 mg/kg for 10 weeks. Vitamin b₆ unsupplemented fish showed reduced lipid contents in muscle, and reduced levels of 22:6n-3 and sum n-3 fatty acids in the hepatic phospholipids PE and PS. In gills, the fatty acid pattern was not influenced by the dietary vitamin B₆ contents. Desaturation and elongation of [1-¹⁴C]18:3n-3 in liver following intraperitoneal injection was not affected by dietary vitamin b₆. Liver weights, the hepatosomatic index and the activity of aspartate aminotransferase and concentration of vitamin B₆ in white muscle increased with increasing dietary vitamin B₆ levels, and were significantly highest in the highest supplemented fish.     

Nutrition of Volvulina Playfair*

SYNOPSIS. Vitamin B₁₂, biotin and thiamine requirements of 10 strains of Volvulina steinii and 1 strain of V. pringsheimii were studied. Vitamin B₁₂ is required for growth of both species, thiamine stimulates growth slightly, and biotin has no discernible effect on growth. The minimum concentration of vitamin B₁₂ giving a growth response in V. steinii, strain SC-2, was 10^?8 g/ml, and maximum growth response was obtained with 1.1 × 10^?7 g/ml. An organic carbon source is required for growth of V. steinii but not of V. pringsheimii. Growth of V. steinii, strain SC-2, occurred in 20 of 21 carbon sources tested. Optimal growth with each carbon source was largely dependent upon pH. Except for pyruvate, acetate, and ethanol, carbon source utilization was light-dependent, and growth in ethanol was reduced in the dark. Isocitric lyase activity was detected in V. steinii grown on acetate medium.     

Enhancement of vitamin B6 levels in rice expressing Arabidopsis vitamin B6 biosynthesis de novo genes

Vitamin B₆ (pyridoxine) is vital for key metabolic reactions and reported to have antioxidant properties in planta. Therefore, enhancement of vitamin B₆ content has been hypothesized to be a route to improve resistance to biotic and abiotic stresses. Most of the current studies on vitamin B₆ in plants are on eudicot species, with monocots remaining largely unexplored. In this study, we investigated vitamin B₆ biosynthesis in rice, with a view to examining the feasibility and impact of enhancing vitamin B₆ levels. Constitutive expression in rice of two Arabidopsis thaliana genes from the vitamin B₆ biosynthesis de novo pathway, AtPDX1.1 and AtPDX2, resulted in a considerable increase in vitamin B₆ in leaves (up to 28.3‐fold) and roots (up to 12‐fold), with minimal impact on general growth. Rice lines accumulating high levels of vitamin B₆ did not display enhanced tolerance to abiotic stress (salt) or biotic stress (resistance to Xanthomonas oryzae infection). While a significant increase in vitamin B₆ content could also be achieved in rice seeds (up to 3.1‐fold), the increase was largely due to its accumulation in seed coat and embryo tissues, with little enhancement observed in the endosperm. However, seed yield was affected in some vitamin B₆‐enhanced lines. Notably, expression of the transgenes did not affect the expression of the endogenous rice PDX genes. Intriguingly, despite transgene expression in leaves and seeds, the corresponding proteins were only detectable in leaves and could not be observed in seeds, possibly pointing to a mode of regulation in this organ.     

Determination of vitamin B6 using an optimized novel TCPO–indolizine–H2O2 chemiluminescence system

Indolizine derivatives are of great interest as fluorescent emitters for peroxyoxalate chemiluminescence. The reaction of peroxyoxalates such as bis‐(2,4,6‐trichlorophenyl) oxalate (TCPO) with H₂O₂ can transfer energy to fluorescer via the formation of dioxetanedione intermediate. Four indolizine derivatives were used as a novel fluorescer in the chemiluminescence (CL) systems in this study. The relationship between CL intensity and the concentration of fluorescer, peroxyoxalate, sodium salicylate and hydrogen peroxide was investigated. Optimum conditions were obtained for four fluorescers and it was found that the indolizine can be used as an efficient green fluorescence emitter. Vitamin B₆ induces a sharp decrease in the CL intensity of the TCPO–hydrogen peroxide–sodium salicylate system. A simple, rapid and sensitive CL method for the determination of vitamin B₆ has been developed. The results showed a linear relationship between vitamin B₆ concentration and peroxyoxalate CL intensity in the range 7.0 × 10⁻⁸–1.0 × 10⁻⁴. A detection limit of 2.3 × 10⁻⁸ M and relative standard deviation (RSD) of < 4.5% were obtained. Copyright © 2014 John Wiley & Sons, Ltd.     

Utilization of n-Paraffins and Vitamin B6 Production by Pichia guilliermondii Wickerham

The accumulation of vitamin B₆ by Pichia guilliermondii Wickerham NK–2 strain grown on hydrocarbon was investigated. Ammonium acetate was more effective than other nitrogen sources tested. Satisfactory utilization by the yeast strain was observed in n-alkanes of C₁₀–C₁₈, and n-pentadecane was the best for vitamin B₆ production. Vitamin B₆ was excreted in the cultural broth mainly in the form of pyridoxal, The maximal vitamin B₆ production was approximately 25 mg per liter of the culture broth.     

Seasonal and Spatial Distribution of Vitamin B12 in a Coastal Area of Eastern Mediterranean Sea

The seasonal and spatial distribution of vitamin B₁₂ was investigated in Eastern Mediterranean (Saronicos Gulf, Aegean Sea). Vitamin B₁₂ concentration had an annual range 0.12–7.93 ng. 1⁻¹ and an annual mean 1.88 ng. 1⁻¹. The statistical analysis of data indicated significant seasonal and regional variations of vitamin B₁₂ in this area and an inverse relationship of this vitamin with chl a. The results showed that the Eastern Mediterranean Sea contains less vitamin B₁₂ than the Western Mediterranean Sea.     

Selective induction of a giant puff in Drosophila hydei by vitamin B6 and derivatives

Vitamin B₆ induces in vivo as well as in vitro the appearance of a puff at region 2–48C in Drosophila hydei. At concentrations of 10^–2 M or lower, region 2–48C is the only region responding to vitamin B₆ provided that oligomycin is present in the incubation medium. Pyridoxal phosphate and pyridoxamine phosphate supplied to medium containing oligomycin induce upon incubation of salivary glands a larger puff at 2–48C. — Puff 2–48C produces large quantities of a unique RNP-product; globular 140–220 Å particles which aggregate to stable complexes of 0.1–0.2 in diameter. Upon continuous in vitro incubation with vitamin B₆, puff 2–48C becomes loaded with these aggregates which have never been observed in any other puff of Drosophila hydei.     

Evaluation of growth and nutritional value of Brassica microgreens grown under red,blue and green LEDs combinations

Microgreens are rich functional crops with valuable nutritional elements that have health benefits when used as food supplements. Growth characterization, nutritional composition profile of 21 varieties representing five species of the Brassica genus as microgreens were assessed under light-emitting diodes (LEDs) conditions. Microgreens were grown under four different LEDs ratios (%); red:blue 80:20 and 20:80 (R₈₀:B₂₀ and R₂₀:B₈₀), or red:green:blue 70:10:20 and 20:10:70 (R₇₀:G₁₀:B₂₀ and R₂₀:G₁₀:B₇₀). Results indicated that supplemental lighting with green LEDs (R₇₀:G₁₀:B₂₀) enhanced vegetative growth and morphology, while blue LEDs (R₂₀:B₈₀) increased the mineral and vitamin contents. Interestingly, by linking the nutritional content with the growth yield to define the optimal LEDs setup, we found that the best lighting to promote the microgreen growth was the green LEDs combination (R₇₀:G₁₀:B₂₀). Remarkably, under the green LEDs combination (R₇₀:G₁₀:B₂₀) conditions, the microgreens of Kohlrabi purple, Cabbage red, Broccoli, Kale Tucsan, Komatsuna red, Tatsoi and Cabbage green, which can benefit human health in conditions with limited food, had the highest growth and nutritional content.     

Probiotic lactic acid bacterium from <Emphasis Type="Italic">kanjika</Emphasis> as a potential source of vitamin B<Subscript>12</Subscript>: evidence from LC-MS,immunological and microbiological techniques

Vitamin B₁₂ was produced by probiotic Lactobacillus plantarum in submerged fermentation (96 h) with successive anaerobic and aerobic phases of 48 h each to give 13 ng vitamin B₁₂/g dry biomass. Sodium cyanide-mediated cell lysis, followed by benzyl alcohol/chloroform/water extraction, improved the release of intracellular vitamin B₁₂ for analysis. The presence of the K⁺ adduct of cyanocobalamin (m/z of 1394) was established using electron spray ionization–mass spectra; growth of a mutant of Escherichia coli in the presence of cyanocobalamin ascertained its bioavailability.     

Effect of vitamin B6 deficiency on pancreatic acpinar cell function

The present study was designed to determine the effect of vitamin B₆ deficiency on pancreatic acinar cell function. Rats were either fed $\text{ad}$$\text{lib}$ or rendered B₆-deficient by a purified B₆-deficient diet; half of the latter being replenished with IP pyridoxine before sacrifice. Body weight, pancreatic weight, RNA and DNA content were decreased in B₆-deficient animals. These changes were considered to be due to inanition resulting from decreased food intake. Amylase content of pancreas in B₆-deficient animals was less compared with B₆-replenished animals. Although slightly higher in B₆-deficient animals, the incorporation of L-phenylalanine¹⁴C into total tissue proteins was not significantly different in the three groups of animals. On B₆-replenishment, incorporation of L-phenylalanine¹⁴C into nascent proteins was diminished in spite of higher tissue amylase and protein content. Vitamin B₆ deficiency decreased total RNA content and adenine-8-¹⁴C incorporation into RNA. DNA content was diminished but incorporation of thymidine-2-¹⁴C into DNA was increased. On replenishment with B₆, thymidine-2-¹⁴C incorporation decreased significantly compared to control animals. Secretion of amylase was diminished commensurate with decreased content. It is concluded from these studies that B₆-deficiency induced DNA injury, decreased RNA turnover and increased protein turnover resulting in diminished amylase content. These data indicate that B₆-deficiency so frequently encountered in alcoholism may contribute to the pancreatic injury in this clinical condition.     

Effect of high temperatures on seed germination of two woody Leguminosae

Cytisus scoparius and Genista florida regenerate after fire by stump-sprouting but also by seed. Seeds of these species were heated to a range of temperatures similar to those registered on the surface soil during natural fires (from 50 to 150 °C) and a range of exposure times (from 1 to 15 min). No germination was observed at high temperatures, 130 °C, when the exposure time was 5 min or more. However, moderate heat treatments (at 70 and 100 °C) significantly increased the rate of germination relative to controls. Cytisus scoparius is more favoured by fire action than Genista florida, with germination rates slightly greater following 100 °C for 5 min and 130 °C for 1 min than after mechanical scarification.     

Enhanced levels of vitamin B(6) increase aerial organ size and positively affect stress tolerance in Arabidopsis

Vitamin B₆ is an essential nutrient in the human diet derived primarily from plant sources. While it is well established as a cofactor for numerous metabolic enzymes, more recently, vitamin B₆ has been implicated as a potent antioxidant. The de novo vitamin B₆ biosynthesis pathway in plants has recently been unraveled and involves only two proteins, PDX1 and PDX2. To provide more insight into the effect of the compound on plant development and its role as an antioxidant, we have overexpressed the PDX proteins in Arabidopsis, generating lines with considerably higher levels of the vitamin in comparison with other recent attempts to achieve this goal. Interestingly, it was possible to increase the level of only one of the two catalytically active PDX1 proteins at the protein level, providing insight into the mechanism of vitamin B₆ homeostasis in planta. Vitamin B₆ enhanced lines have considerably larger vegetative and floral organs and although delayed in pre‐reproductive development, do not have an altered overall morphology. The vitamin was observed to accumulate in seeds and the enhancement of its levels was correlated with an increase in their size and weight. This phenotype is predominantly a consequence of embryo enlargement as reflected by larger cells. Furthermore, plants that overaccumulate the vitamin have an increased tolerance to oxidative stress providing in vivo evidence for the antioxidant functionality of vitamin B₆. In particular, the plants show an increased resistance to paraquat and photoinhibition, and they attenuate the cell death response observed in the conditional flu mutant.     

VITAMIN B12-BINDER AND OTHER ALGAL INHIBITORS1

Euglena gracilis Klebs, Poterioochromonas malhamensis (Pringsheim) Peterfi, Monochrysis lutheri Droop, Isochrysis galbana Parke and Phaeodactylum tricornutum Bohlin are known to release into the medium a substance which binds free vitamin B₁₂. The binder, apparently a glycoprotein, makes vitamin B₁₂ unavailable and inhibits growth of vitamin B₁₂-requiring microorganisms. Culture filtrates of selected marine diatoms, chrysophytes, cryptophytes, dinoflagellates and green algae contained the binder, indicating that binder release was not restricted to any algal group. However the three prokaryotic bluegreens tested do not produce B₁₂-binder. Production is also independent of the nutritional requirements of the donor, being produced by autotrophs and auxotrophs. The binders produced by these marine species have similar properties: they are heat labile; inhibition is not species-specific; it is competitive, being reversed by adding B₁₂. Production increases with density of the culture and is not restricted to stationary or scenescent cells. The marine species tested produced much less B₁₂ than the freshwater Euglena and Poterioochromonas; the inhibition is reversed by 20–50 ng · 1^?1 of B₁₂ for marine species which reach moderate densities and by 150–300 ng · 1^?1 B₁₂ for the densely growing species. Consequently the binder may affect the growth of B₁₂-requiring species only in environments like the open ocean poor in B₁₂. By contrast, the marine algae produce other inhibitors which are often heat stable and very inhibitory. These inhibitors, being species-specific and less labile, may be more important in affecting the succession of algal species in natural waters.     

Regeneration of plants from callus cultures of Origanum vulgare L.

Investigations were undertaken to achieve rapid multiplication and improvement of Origanum vulgare (a herbaceous, ornamental plant well known for its aromatic and medicinal value) through plant regeneration from callus. The explants (cotyledons, hypocotyl and root segments) excised from 15 d old aseptic seedlings were cultured on Gamborg's B₅ medium supplemented with 2,4-D, NAA and BAP individually and in various combinations (at concentrations of 0,10^–7,10^–6 and 10^–5 M). Best callus induction was noted on medium with 10^–7 M 2,4-D alone. The cotyledonary expiants proved to be the best source for compact and nodulated callus. The subcultured cotyledonary calli showed shoot induction when transferred onto media supplemented with BAP alone orin combination with 10^–7M or 10^–6MNAA. However, 10^–5M NAA completely suppressed the shoot inducing ability of BAP. In general, NAA promoted root induction from all explants used including cotyledonary callus. Best shoot induction was obtained on medium supplemented with 10^–6M BAP+10^–6MNAA. Both IBA and NAA at 10^–6 M proved to be equally effective in induction of roots from the cut ends of 15–20 mm long shoots (excised from callus) in half-strength B₅ liquid medium. Rooted shoots were successfully re-established in soil under controlled conditions.Abbreviations 2,4-D 2,4 dichlorophenoxyacetic acid - IBA indole-3-butyric acid - NAA -naphthaleneacetic acid - BAP 6-benzylaminopurine     

Analysis of fatty acids,proteins and ethereal extract in honeybee pollen - Considerations of their floral origin

Chemical analysis was made of the ethereal extract, fatty acids, protein and sugars of corbicula pollen as these are specific characters selected by the honeybee from plant species as a source of pollen for the hive. This group of analyses was carried out using balls of monospecific pollen of the following individual taxa which represent more than 5% of the total pollen collected by the honeybee: Castanea sativa, Erica, Eucalyptus, Halimium alyssoides, Quercus robur, Raphanus raphanistrum, Rubus and Cytisus scoparius-type. The ethereal extract content was similar for the total pollen in all the hives. The percentage composition of fatty acids, both saturated and unsaturated and their diversity allowed the relationship between fatty acids and plant species to be found, which contributed to the final content in the hives. In this way tridecanoic acid was related with Cytisus scoparius-type; palmitoleic acid with Castanea sativa, Erica, Eucalyptus and Quercus robur; behenic acid with Rubus and Raphanus raphanistrum; and isopalmitic acid with Rubus. Until now isopalmitic acid has not been cited in other studies as a component of honeybee pollen. The fatty acid content of pollen has also proved to be useful in determining geographical origin of this product. The pollen was found to be rich in essential fatty acids of interest for human nourishment. The protein content was high in hives and in the pollen of the individual taxa, varied between the 29.6% and 14%. The fructose content was higher than glucose. It was noticeable that pollen of Rubus was highest in glucose (21%) and Castanea sativa in fructose (26.3%). Water content of corbicula pollen was below 10%.     

The Pseudoenzyme PDX1.2 Boosts Vitamin B6 Biosynthesis under Heat and Oxidative Stress in Arabidopsis

Vitamin B₆ is an indispensable compound for survival, well known as a cofactor for numerous central metabolic enzymes and more recently for playing a role in several stress responses, particularly in association with oxidative stress. Regulatory aspects for the use of the vitamin in these roles are not known. Here we show that certain plants carry a pseudoenzyme (PDX1.2), which is involved in regulating vitamin B₆ biosynthesis de novo under stress conditions. Specifically, we demonstrate that Arabidopsis PDX1.2 enhances the activity of its catalytic paralogs by forming a heterododecameric complex. PDX1.2 is strongly induced by heat as well as singlet oxygen stress, concomitant with an enhancement of vitamin B₆ production. Analysis of pdx1.2 knockdown lines demonstrates that boosting vitamin B₆ content is dependent on PDX1.2, revealing that this pseudoenzyme acts as a positive regulator of vitamin B₆ biosynthesis during such stress conditions in plants.