Determination of Vitamin B3 Vitamer (Nicotinamide) and Vitamin B6 Vitamers in Human Hair Using LC-MS/MS

Water-soluble B vitamins participate in numerous crucial metabolic reactions and are critical for maintaining our health. Vitamin B deficiencies cause many different types of diseases, such as dementia, anaemia, cardiovascular disease, neural tube defects, Crohn’s disease, celiac disease, and HIV. Vitamin B3 deficiency is linked to pellagra and cancer, while niacin (or nicotinic acid) lowers low-density lipoprotein (LDL) and triglycerides in the blood and increases high-density lipoprotein (HDL). A highly sensitive and robust liquid chromatography–tandem mass spectroscopy (LC/MS-MS) method was developed to detect and quantify a vitamin B3 vitamer (nicotinamide) and vitamin B6 vitamers (pyridoxial 5′-phosphate (PLP), pyridoxal hydrochloride (PL), pyridoxamine dihydrochloride (PM), pridoxamine-5′-phosphate (PMP), and pyridoxine hydrochloride (PN)) in human hair samples of the UAE population. Forty students’ volunteers took part in the study and donated their hair samples. The analytes were extracted and then separated using a reversed-phase Poroshell EC-C18 column, eluted using two mobile phases, and quantified using LC/MS-MS system. The method was validated in human hair using parameters such as linearity, intra- and inter-day accuracy, and precision and recovery. The method was then used to detect vitamin B3 and B6 vitamers in the human hair samples. Of all the vitamin B3 and B6 vitamers tested, only nicotinamide was detected and quantified in human hair. Of the 40 samples analysed, 12 were in the range 100–200 pg/mg, 15 in the range 200–500 pg/mg, 9 in the range of 500–4000 pg/mg. The LC/MS-MS method is effective, sensitive, and robust for the detection of vitamin B3 and its vitamer nicotinamide in human hair samples. This developed hair test can be used in clinical examination to complement blood and urine tests for the long-term deficiency, detection, and quantification of nicotinamide.

Production of α-amylase(s) by Aspergillus flavus, F7 attacking water hyacinth ground preparation (WHGP) under solid state fermentation

Some environmental and nutritional parameters controlling the biosynthesis of α-amylase from Aspergillus flavus, F7 attacking the water hyacinth have been investigated under solid state fermentation conditions for maximum amylase production. The following optima’s were recorded for the highest α-amylase yield; Incubation period 7 days; temperature, 30oC; pH, 5; inoculum size, 3X108 spores/ml; flask volume 100 ml capacity; hyacinth fresh weight 5 g; tap water, 25 ml. Under these conditions, starch showed remarkable stimulatory effect; nitrogen sources and amino acids have no stimulatory effect. Pyridoxal hydrochloride, B6 at a concentration of 200 ppm exhibited a stimulatory effect on biosynthesis of α-amylase.

Effect of Double Substitution in Cationic Chitosan Derivatives on DNA Transfection Efficiency

Recently, much effort has been expended on the development of non-viral gene delivery systems based on polyplexes of nucleic acids with various cationic polymers. Natural polysaccharide derivatives are promising carriers due to their low toxicity. In this work, chitosan was chemically modified by a reaction with 4-formyl-n,n,n-trimethylanilinium iodide and pyridoxal hydrochloride and subsequent reduction of the imine bond with NaBH4. This reaction yielded three novel derivatives, n-[4-(n’,n’,n’-trimethylammonium)benzyl]chitosan chloride (TMAB-CS), n-[(3-hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridine)methyl]chitosan chloride (Pyr-CS), and n-[4-(n’,n’,n’’-trimethylammonium)benzyl]-n-[(3-hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridine)methyl]chitosan chloride (PyrTMAB-CS). Their structures and degrees of substitution were established by 1H NMR spectroscopy as DS1 = 0.22 for TMAB-CS, DS2 = 0.28 for Pyr-CS, and DS1 = 0.21, DS2 = 0.22 for PyrTMAB-CS. Dynamic light scattering measurements revealed that the new polymers formed stable polyplexes with plasmid DNA encoding the green fluorescent protein (pEGFP-N3) and that the particles had the smallest size (110–165 nm) when the polymer:DNA mass ratio was higher than 5:1. Transfection experiments carried out in the HEK293 cell line using the polymer:DNA polyplexes demonstrated that Pyr-CS was a rather poor transfection agent at polymer:DNA mass ratios less than 10:1, but it was still more effective than the TMAB-CS and PyrTMAB-CS derivatives that contained a quaternary ammonium group. By contrast, TMAB-CS and PyrTMAB-CS were substantially more effective than Pyr-CS at higher polymer:DNA mass ratios and showed a maximum efficiency at 200:1 (50%–70% transfected cells). Overall, the results show the possibility of combining substituent effects in a single carrier, thereby increasing its efficacy.

Design, Synthesis and Anti-tuberculosis Activity of Hydrazones and N-acylhydrazones Containing Vitamin B6 and Different Heteroaromatic Nucleus

Background: The term vitamin B6 refers to a set of six compounds, pyridoxine,pyridoxal ,and pyridoxamine and their phosphorylated forms, among which pyridoxal 5´-phosphate (PLP) is the most important and active form acting as a critical cofactor. These compounds are very useful in medicinal chemistry because of their structure and functionalities and are also used in bioinorganic chemistry as ligands for complexation with metals. Methods: In this study, a series of hydrazones 1a-g and N-acylhydrazones 2a-f containing vitamin B6 have been synthesized from commercial pyridoxal hydrochloride and the appropriate aromatic or heteroaromatic hydrazine or N-acylhydrazine. All synthesized compounds have been fully characterized and tested against Mycobacterium tuberculosis. Results: Among the N-acylhydrazones derivatives 2a-f, 2d (para- pyridine substituted Nacylhydrazone; MIC = 10.90 µM) exhibited the best activity. The ortho-pyridine derivative 2b exhibited intermediate activity (MIC = 87.32 µM), and the meta-pyridine derivative 2c was inactive. In case of the hydrazone series 1a-g, 7-chloroquinoxaline derivative 1f (MIC = 72.72 µM) showed the best result, indicating that the number of nitrogen and chlorine atoms in the radical moiety play an important role in the anti-tuberculosis activity of the quinoxaline derivatives (1f and 1g). Conclusion: The data reported herein indicates that the isoniazid derivative 2d (MIC = 10.90 µM) exhibited the best activity in the N-acylhydrazone series and; the quinoxaline nucleus derivative 1f (MIC = 72.72 µM) was the most active compound in the hydrazone series.

Synthesis, Characterization and in vitro Biological Evaluation of a New Schiff Base Derived from Drug and its Complexes with Transition Metal Ions

New series of copper (II), cobalt (II), zinc (II), nickel (II), manganese (II), iron (II) complexes of a novel Schiff base were prepared by the condensation of sulphadizine and pyridoxal hydrochloride. The ligand and metal complexes were characterized by utilizing different instrumental procedures like microanalysis, thermogravimetric examination and spectroscopy. The integrated ligand and transition metal complexes were screened against various bacteria and fungus. The studies demonstrated the enhanced activity of metal complexes against reported microbes when compared with free ligand.