Internal Standard an Important Analyte Use in Drug Analysis by Liquid Chromatography Mass Spectrometry- An Article

Internal standard is an external compound which is mixed with targeted analytical solution and matrix as a constant concentration and use for preparing calibration standard curve by using ratio of analyte area and internal standard area with analyte concentration and internal standard concentration. This calibration curve used for quantification of unknown concentration of anlayte of interest. This article provide necessary information about internal standard like its selection procedure, characterization, types and response factor , to all analyst who are connected with drug analysis. This article is more important and I think first article which focuses a clear idea about internal standard use in drug analysis.

On the Oval Shapes of Beach Stones

This article introduces a new stochastic non-isotropic frictional abrasion model, in the form of a single short partial integro-differential equation, to show how frictional abrasion alone of a stone on a planar beach might lead to the oval shapes observed empirically. The underlying idea in this theory is the intuitive observation that the rate of ablation at a point on the surface of the stone is proportional to the product of the curvature of the stone at that point and the likelihood the stone is in contact with the beach at that point. Specifically, key roles in this new model are played by both the random wave process and the global (non-local) shape of the stone, i.e., its shape away from the point of contact with the beach. The underlying physical mechanism for this process is the conversion of energy from the wave process into the potential energy of the stone. No closed-form or even asymptotic solution is known for the basic equation, which is both non-linear and non-local. On the other hand, preliminary numerical experiments are presented in both the deterministic continuous-time setting using standard curve-shortening algorithms and a stochastic discrete-time polyhedral-slicing setting using Monte Carlo simulation.

Investigation of Two Precipitation Methods for Extracting Immunoglobulin Y (IgY) from Egg Yolks

Two groups of hens (control and immunization group) were arranged in an experimental design with an immunization schedule of 3 injections of BSA antigen. IgY antibodies were extracted from egg yolks by two precipitation processes (chloroform and polyethylene glycol precipitates) and quantified using a standard curve of protein concentration. The purification of IgYwas confirmed by SDS-PAGE. Total protein extracted from egg yoks were less contaminated with yellow pigments (lutein and zeaxanthin) by using chloroform precipitate. The 2nd week post-immunization, IgY concentration increased respectively to 3903 ± 726 μg.ml-1 (chloroform extraction process) and 2937 ± 294 μg.ml-1 (PEG extraction process) (P < 0.01). After 3rdimmunization, IgY level obtaining from in immunization group extracted by chloroform process (6633 ± 1166 μg.ml-1) increased 2.7 times higher than that in control group (2482 ± 414 μg.ml-1). Whereas IgY concentrations obtained from PEG extraction process were not significantly different between the experimental group and control group. Chloroform and PEG precipitation methods had the same protein profile on the SDSPAGE. IgY antibody was identified by the presence of bands corresponding with IgY heavy chain (67-70 kDa) and IgY light chain (25 kDa) for both precipitation processes.

Measuring Proviral HIV-1 DNA: Hurdles and Improvements to an Assay Monitoring Integration Events Utilising Human Alu Repeat Sequences

Integrated HIV-1 DNA persists despite antiretroviral therapy and can fuel viral rebound following treatment interruption. Hence, methods to specifically measure the integrated HIV-1 DNA portion only are important to monitor the reservoir in eradication trials. Here, we provide an up-to-date overview of the literature on the different approaches used to measure integrated HIV-1 DNA. Further, we propose an implemented standard-curve free assay to quantify integrated HIV-1 DNA, so-called Alu-5LTR PCR, which utilises novel primer combinations. We tested the Alu-5LTR PCR in 20 individuals on suppressive ART for a median of nine years; the results were compared to those produced with the standard-free Alu-gag assay. The numbers of median integrated HIV-1 DNA copies were 5 (range: 1–12) and 14 (5–26) with the Alu-gag and Alu-5LTR, respectively. The ratios between Alu-gag vs Alu-5LTR results were distributed within the cohort as follows: most patients (12/20, 60%) provided ratios between 2–5, with 3/20 (15%) and 5/20 (25%) being below or above this range, respectively. Alu-5LTR assay sensitivity was also determined using an “integrated standard”; the data confirmed the increased sensitivity of the assay, i.e., equal to 0.25 proviruses in 10,000 genomes. This work represents an improvement in the field of measuring proviral HIV-1 DNA that could be employed in future HIV-1 persistence and eradication studies.

Sustainable Production of Bioethanol by Zymomonas mobilis and Saccharomyces cerevisiae using Rice Husk and Groundnut Shell as Substrates

Background of Study: Plant waste such as rice husk and groundnut shell are generated in large amounts, these waste presents a tremendous pollution to the environment. Worldwide, these wastes are often simply dumped into landfills and oceans or used as animal feeds. The recovery of food processing wastes as renewable energy sources represents a sustainable option for the substitution of fossil energy in order to minimize environmental damages and to meet energy demands of the growing population. Aim: To produce bioethanol from rice husk and groundnut shell using local strains of Zymomonas mobilis and Saccharomyces cerevisiae. Place and Duration of Study: Conducted at the Microbiology Laboratory of Abubakar Tafawa Balewa University Bauchi, Bauchi state, Nigeria, between April to June, 2021. Methods: Groundnut shell and Rice husk were collected from local milling center. The wastes were powdered, sieved and used as carbon source. Proximate composition of the subsrate was done and the total carbohydrate was determined by difference. The sum of the percentage moisture, ash, crude lipid, crude protein and crude fibre was subtracted from 100. Zymomonas mobilis and Saccharomyces cerevisiae were isolated from rotten sweet oranges and locally fermented beverage (‘kunun-zaki’) respectively by growing them on Malt Yeast Peptone Glucose Agar (MYPGA) after which they were further screened for their ability to tolerate ethanol and they serve as organisms for fermentation. The enzyme α- amylase was used for hydrolysis. The fermented substrates were distilled at 78oC and the distillate was collected as bioethanol in a conical flask. UV-VIS spectrophotometer was used to determine the absorbance of each concentration (0, 0.2, 0.4, 0.6 and 0.8cm3) of reducing sugar content of the hydrolysates and the bioethanol produced by developing a standard curve at a wavelength of 491nm and 588nm respectively. The concentration of reducing sugar and bioethanol was determined using a reference line from the Standard curve. Results: Proximate analysis done shows that rice husk have 70.09% carbohydrates while groundnut shell has 65.09% carbohydrates. Groundnut shell yielded the highest reducing sugar of 5.096%. Rice husk yielded the lowest quantity of reducing sugar with a total yield of 2.962%. Maximum concentration of bioethanol of 0.971% was produced from the combination of Saccharomyces cerevisiae and Zymomonas mobilis from groundnut shell. The lowest concentration of 0.121% of bioethanol was produced when Saccharomyces cerevisiae was used on rice husk hydrolysates. The synergistic relationship of Saccharomyces cerevisiae and Zymomonas mobilis yielded the maximum bioethanol when compared with the yield obtained when the organisms were used singly. Zymomonas mobilis produced highest bioethanol content when the organisms are used single. Conclusion: This study demonstrates the potentiality of local strains of Saccharomyces cerevisiae and Zymomonas mobilis isolated from rotten sweet orange and locally fermented beverage (‘kunun-zaki’) to produce bioethanol by fermenting the rice husk and groundnut shell hydrolysates.

Application of a commercial Salmonella real-time polymerase chain reaction (PCR) assay for the detection and quantitation of Salmonellaenterica in poultry ceca

Foodborne Salmonellosis is commonly associated with poultry and poultry products necessitating continued development of pre- and post-harvest food safety interventions and risk management strategies. Evaluating technologies and strategies is limited by availability of cost-effective, rapid laboratory methods. The objective of this work was to evaluate a commercial, qualitative PCR assay and its novel quantitative application to detect and enumerate Salmonella in poultry ceca as an analytical matrix. Ceca were collected at harvest, contents homogenized, and paired samples evaluated with Buffered Peptone Water (BPW) and BAX® MP + Supplement (MPS) pre-enrichment broths followed by PCR screening on BAX® System Q7 (PCR) and by isolation. Additional ceca were inoculated with Salmonella to develop a standard curve for the BAX® System SalQuant™ quantitative PCR application (QA), then estimates were obtained by the QA and Most Probable Number (MPN) methods. For pre-enrichment media, PCR outcomes performed equivalently to culture isolation for detecting Salmonella in ceca with 95.65% and 87.88% sensitivity and 82.00% and 100.00% specificity (P=0.074) for BPW and MPS, respectively. However, at the sample-level, BPW performed significantly worse (47.92%) than MPS (68.75%) for overall isolation of Salmonella (P&lt;0.0001). Post-standard curve development, the mean QA estimates obtained for the inoculated samples were 1.14 (95% CI; 0.62 - 1.66), 1.79 (95% CI; 1.50- 2.08), 2.91 (95% CI; 2.65 - 3.17) and 3.76 (95% CI; 3.26 - 4.25), respectively for each targeted inoculation of 1.0, 2.0, 3.0 and 4.0 Log10 CFU/mL and within or comparable to 95% confidence intervals of paired MPN estimates. These data demonstrate performance of MPS for the detection and isolation of Salmonella enterica from poultry ceca when screening with PCR and indicate the QA may be useful as an alternative tool to estimate Salmonella concentrations in ceca, which may support pre-harvest food safety activities.

Evaluation of real time PCR for the detection of Mycobacterium avium subsp. paratuberculosis in faecal samples of cattle

The efficiency and suitability of a MAP F57 based SYBR Green qPCR assay for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) using a set of known MAP positive (12) and MAP negative (23) DNA samples that were previously identified by conventional IS 900 PCR were assessed. These DNA samples were isolated in our previous study from faecal samples collected from cattle in the livestock farms under government sector with a previous history of Johne’s disease. The MAP F57 qPCR was able to identify all the positive samples accurately and rapidly with Cq values ranging from 20-29. The efficiency of qPCR using recombinant plasmid for standard curve was 0.991 and limit of detection was 10 MAP organisms per microlitre of DNA sample.

Biomolecular Characterization of Bacillus tequilensis A1C1 Isolated from Soil and Chromatographic Analysis of D-serine in its Cellular Fraction

The current work was carried out to investigate serine enantiomers in bacterial cells. The bacteria isolated from the pomace dumping soil site (bacteria id A1C1) showed maximum growth (O.D600 = 1.97±0.4 X 109cells/ml) within 48h in the minimal salt media supplemented with L-serine. The isolated strain was identified as ‘Bacillus tequilensis’ through 16sRNA sequencing. The study’s peculiarity reflects the fact that the isolated strain was explored for the first time to detect the presence of serine enantiomers. The strain was quantified for D-serine content by using RP-HPLC. The D-serine concentration was calculated as 0.919±0.02 nM in the bacterial cellular fraction by using a standard curve plot and linear curve equation. Further, recovery % was also calculated for the spiked samples which vary from 85-90%. The optimum growth parameters were recorded as 37℃±0.5, 150±0.5 RPM, and 7±0.5pH. The strain was Gram-positive, rod shape, large, irregular, off-white-coloured, and synthesized endospores. A1C1 showed positive results (within 14±2h of incubation) for indole production, lactose fermentation, and protease (0.9 mm, clear zone). The antibacterial assay showed 5% and 2% efficacy of the extracellular fraction against MTCC 40 and MTCC 11949 respectively within 12h of incubation. These results demonstrate that Bacillus tequilensis A1C1 has antibacterial activity, the potential to secrete extracellular enzymes, and D-serine content in the intracellular fraction of the cultivated cells. Given results demonstrate the industrial significance and implication of the isolated strain for the synthesis of commercially valuable products.

Determination of Time of Death Based on Blood Ring Formation and RNA Degradation

Time of death (TOD) determination is crucial in criminal cases. The method used to determine the TOD so far is only based on the state of the corpse found, therefore a new method is needed to improve the accuracy of the TOD determination. This study aims to determine the TOD based on a new method, namely the formation of blood rings and RNA degradation. Blood is commonly found in crime scenes. Blood consists of liquid part that is plasma and cellular part consisting of erythrocytes, leukocyte, and thrombocytes. The composition of blood as a liquid that contains dissolved solids makes the drops of dried blood forming “coffee ring effect”, which is a ring-like form on the perimeter of a blood drop. Coffee ring effect is used as an indicator of time by looking at the thickness of the ring formed from the perimeter of the blood drop to the middle which increases with time. RNA degradation was observed using Peptidylprolyl isomerase A (PPIA) gene. The PPIA gene is found in leukocyte and is used to see the degradation of RNA per 30 minutes period using the RT-PCR and qPCR methods. Degradation was observed by comparing the cycle threshold (ct) value of the standard curve with the ct value of the samples per unit time. TOD could be determined by the percentage of the blood ring thickness up until 120th minutes, and by observing the degradation of RNA until the 60th minute, after that the RNA had completely degraded.

Penetapan Kadar Tanin pada Teh Hitam Kering Produksi Pekalongan dengan Metode Spektrofotometri UV-Vis

Tea plants have benefits as antioxidants and help protect body cells from the bad effects of free radicals. The content in dried black tea leaves has tannin compounds that have a good effect on the body. The purpose of this study was to determine the difference in tannin levels in dry tea produced by Pekalongan with UV-Vis Spectrophotometry and to find out that all samples of tea brands met the requirements for consumption limits in tea. The data obtained were the average tannin content of black tea leaf extract from various samples with concentrations used of 8, 16, 24, 32, and 40 g/ml. Data analysis to determine the tannin content using the standard curve method, linear regression y = a + bx. The results obtained from the TLC qualitative test contained sample and comparison spots at UV 254 nm, namely Rf T1 of 0.84 cm, T2, T4, T5, T8, T9 of 0.85 cm, on samples T3, T7, T10, T11 obtained an Rf value of 0.86 cm which has the same Rf value as the comparison of catechins. and the sample T6 obtained an Rf value of 0.81 cm. As for the quantitative test, the highest levels were obtained in samples T1, T3, T6, T8, T10 as much as 0.004 ± 0 g/g while the lowest levels were obtained in samples T2, T4, T5, T7, T9, T11 as much as 0.003 ± 0 g/g It can be concluded that the circulating tannins produced by Pekalongan meet the consumption limit requirements.Keywords: Content; Tea; Tannins; UV-Vis Spectrophotometry AbstrakTanaman teh memiliki manfaat sebagai antioksidan dan membantu melindungi sel-sel tubuh dari efek buruk radikal bebas. Kandungan pada daun teh hitam kering mempunyai senyawa tanin yang memberikan efek baik bagi tubuh. Tujuan penelitian ini mengetahui adanya perbedaan kadar tanin pada teh kering produksi Pekalongan dengan metode Spektrofotometri UV-Vis dan mengetahui semua sampel merk teh memenuhi persyaratan batas konsumsi dalam teh. Data yang didapatkan adalah data rata-rata kadar tanin dari ekstrak daun teh hitam dari berbagai sampel dengan konsentrasi yang digunakan 8, 16,24, 32,dan40µg/ml. Analisis data untuk mengetahui kadar tanin dengan menggunakan metode kurva standar, regresi linier y = a + bx. Hasil yang diperoleh dari uji kualitatif KLT terdapat bercak noda sampel dan pembanding pada UV 254 nm, yaitu Rf T1 sebesar 0,84 cm , T2,T4,T5,T8, T9 sebesar 0,85 cm, pada sampel T3,T7,T10,T11 diperoleh nilai Rf sebesar 0,86 cm yang nilai Rf nya sama dengan pembanding katekin. dan pada sampel T6 diperoleh nilai Rf sebesar 0,81 cm. Adapun untuk uji kuantitatif nya diperoleh kadar tertinggi pada sampel T1, T3, T6, T8, T10 sebanyak 0,004 ± 0 g/g sedangkan kadar terendah diperoleh sampel T2, T4, T5, T7, T9, T11 sebanyak 0,003 ± 0 g/g, Hal ini dapat disimpulkan bahwa tanin yang beredar produksi Pekalongan memenuhi syarat batas konsumsi.Kata kunci: Kadar; Teh; Tanin; Spektrofometri UV-Vis