Growth and Mass Spectrometry Profile of Alternaria Alternata Pigment Grown in Maize Grain extract

Alternaria species are common saprophytes found in a variety of habitats as ubiquitous agents of decay. Alternaria spp. produces about sixty different secondary metabolites. In the present investigation, growth and production of pigment from Alternaria alternata was studied in maize grain extract at pH 4-9. The reddish brown pigment was extracted, estimated and partially purified by fractionation. Through mass spectrometry, major constituents of pigment from Alternaria alternata such as Tenuazoic acid (m/z 198), Stemphyperylenol (m/z 253), Alterperylenol (m/z 351), Alternariol (m/z 259.200), Altenuene (m/z 292), Alternarienoic acid (m/z 279.35) and Alternariol 5 methyl ether (m/z 273.20) were identified. The bio-prospecting of these secondary metabolites in industrial applications is also discussed

Saliva-based linezolid monitoring on a mobile UV spectrophotometer

Background: In TB, therapeutic drug monitoring (TDM) is recommended for linezolid; however, implementation is challenging in endemic settings. Non-invasive saliva sampling using a mobile assay would increase the feasibility of TDM. Objectives: To validate a linezolid saliva assay using a mobile UV spectrophotometer. Methods: The saliva assay was developed using NanoPhotometer NP80 (R) and linezolid concentrations were quantified using second-order derivative spectroscopy. Sample preparation involved liquid-liquid extraction of saliva, using saturated sodium chloride and ethyl acetate at 1:1:3 (v/v/v). The assay was validated for accuracy, precision, selectivity, specificity, carry-over, matrix effect, stability and filters. Acceptance criteria were bias and coefficient of variation (CV) Results: Linezolid concentrations correlated with the amplitude between 250 and 270 nm on the second-order derivative spectra. The linezolid calibration curve was Linear over the range of 3.0 to 25 mg/L (R-2 = 0.99) and the LLOQ was 3.0 mg/L. Accuracy and precision were demonstrated with bias of -7.5% to 2.7% and CV Conclusions: We validated a UV spectrophotometric assay using non-invasive saliva sampling for linezolid. The next step is to demonstrate clinical feasibility and value to facilitate programmatic implementation of TDM

N-acetyltransferase gene polymorphisms & plasma isoniazid concentrations in patients with tuberculosis

Background & objectives: Variations in the N-acetyltransferase (NAT2) gene among different populations could affect the metabolism and disposition of isoniazid (INH). This study was performed to genotype NAT2 gene polymorphisms in tuberculosis (TB) patients from Chennai, India, and compare plasma INH concentrations among the different genotypes. Methods: Adult patients with TB treated in the Revised National TB Control Programme (RNTCP) in Chennai, Tamil Nadu, were genotyped for NAT2 gene polymorphism, and two-hour post-dosing INH concentrations were compared between the different genotypes. Plasma INH was determined by high-performance liquid chromatography. Genotyping of the NAT2 gene polymorphism was performed by real-time polymerase chain reaction method. Results: Among the 326 patients genotyped, there were 189 (58%), 114 (35%) and 23 (7%) slow, intermediate and fast acetylators, respectively. The median two-hour INH concentrations in slow, intermediate and fast acetylators were 10.2, 8.1 and 4.1 μg/ml, respectively. The differences in INH concentrations among the three genotypes were significant (P<0.001). Interpretation & conclusions: Genotyping of TB patients from south India for NAT2 gene polymorphism revealed that 58 per cent of the study population comprised slow acetylators. Two-hour INH concentrations differed significantly among the three genotypes

Efficacy and tolerability of a 4-month ofloxacin-containing regimen compared to a 6-month regimen in the treatment of patients with superficial lymph node tuberculosis: a randomized trial

Tuberculosis (TB) lymphadenitis is the most common form of extra-pulmonary TB, and the treatment duration is six months. This non-inferiority based randomized clinical trial in South India evaluated the efficacy and safety of a four-month ofloxacin containing regimen in tuberculosis lymphadenitis (TBL) patients