Environmental and Biotechnologies

A reverse phase stability indicating HPLC method for simultaneous determination of two antispasmodic drugs in pharmaceutical parenteral dosage forms (injectable) and in serum has been developed and validated. Mobile phase ingredients consist of Acetonitrile : buffer : sulfuric acid 0.1 M (50 : 50 : 0.3 v/v/v), at flow rate 1.0 mL/min using a Hibar μBondapak ODS C18 column monitored at dual wavelength of 266 nm and 205 nm for phloroglucinol and trimethylphloroglucinol, respectively. The drugs were subjected to stress conditions of hydrolysis (oxidation, base, acid, and thermal degradation). Oxidation degraded the molecule drastically while there was not so much significant effect of other stress conditions. The calibration curve was linear with a correlation coefficient of 0.9999 and 0.9992 for PG and TMP, respectively. The drug recoveries fall in the range of 98.56% and 101.24% with 10 pg/mL and 33 pg/mL limit of detection and limit of quantification for both phloroglucinol and trim...

A stability indicating, accurate, specific, precise, and simple reverse phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for the simultaneous determination of Phloroglucinol (PGD) and Trimethylphloroglucinol (TMP) in bulk, pharmaceutical dosage forms of tablet and in body fluid. Methanol: Buffer: Sulfuric Acid 0.1mol/l (60:40:03) was the mobile phase at flow rate 1.0 ml/min using a Symmetry C18 column monitored at 234nm. The API’s were subjected to stress conditions of hydrolysis (acid, base, oxidation, and thermal degradation). Maximum degradation was observed in acid and 35% H2O2 while found stable in the other stress conditions. The calibration curve was linear with a correlation coefficient of more than 0.9995 for both drugs. The averages of the absolute and relative recoveries were found to be 100.154% and 99.993% for Phloroglucinol and Trimethylphloroglucinol respectively, with 30pg/ml LOD and with 300pg/ml LOQ. The developed meth...

The thermal and catalytic pyrolysis of two kinds of Tetra Pak waste (TP-1 and TP-2) over three different acidic catalysts—HZSM-5(SiO2/Al2O3, 30), HBeta (38), and Al-MCM-41(20)—were investigated in this study. Tetra Pak (TP) wastes consist of composite material comprising kraft paper, polyethylene (PE) film, and aluminum foil. Thermal decomposition behaviors during the pyrolysis of TPs were monitored using a thermogravimetric (TG) analyzer and tandem micro reactor-gas chromatography/mass spectrometry (TMR-GC/MS). Neither the interaction between the non-catalytic pyrolysis intermediates of kraft paper and PE, nor the effect of aluminum foil have been monitored during the non-catalytic TG analysis of TPs. The maximum decomposition temperatures of PE in TP-1 shifted from 465 °C to 432 °C by HBeta(38), 439 °C by HZSM-5(30), and 449 °C by Al-MCM-41(20), respectively. The results of the TMR-GC/MS analysis indicate that the non-catalytic pyrolysis of TPs results in the formation of large am...

The pyrolysis of waste electronically heated tobacco (EHT), consisting of tobacco leaves (TL), a poly-lactic acid (PLA) filter, and a cellulose acetate (CA) filter, was investigated using thermogravimetric (TG) and pyrolyzer–gas chromatography/mass spectrometry (Py-GC/MS) analysis. The pyrolytic properties of waste EHT obtained after smoking were comparable to those of fresh EHT. Although the maximum decomposition temperatures (TmaxS) of waste TL and CA were similar to those of fresh EHT components, the Tmax of waste PLA was slightly higher than that of fresh PLA due to smoldering. The Tmaxs of PLA and CA were lowered when they were co-pyrolyzed with TL due to interactions between pyrolysis intermediates. The apparent activation energies for the non-isothermal pyrolysis of waste EHT components were higher than those of fresh EHT components. Py-GC/MS analysis results indicated that considerable amounts of chemical feedstocks, such as nicotine and limonene from TL, caprolactone and la...

A reverse phase stability indicating HPLC method for simultaneous determination of two antispasmodic drugs in pharmaceutical parenteral dosage forms (injectable) and in serum has been developed and validated. Mobile phase ingredients consist of Acetonitrile : buffer : sulfuric acid 0.1 M (50 : 50 : 0.3 v/v/v), at flow rate 1.0 mL/min using a HibarμBondapak ODS C18column monitored at dual wavelength of 266 nm and 205 nm for phloroglucinol and trimethylphloroglucinol, respectively. The drugs were subjected to stress conditions of hydrolysis (oxidation, base, acid, and thermal degradation). Oxidation degraded the molecule drastically while there was not so much significant effect of other stress conditions. The calibration curve was linear with a correlation coefficient of 0.9999 and 0.9992 for PG and TMP, respectively. The drug recoveries fall in the range of 98.56% and 101.24% with 10 pg/mL and 33 pg/mL limit of detection and limit of quantification for both phloroglucinol and trimet...

High-density polyethylene (HDPE) was co-fed into the catalytic pyrolysis (CP) of mandarin peel (MP) over different microporous catalysts, HY and HZSM-5, with different pore and acid properties. Although the non-catalytic decomposition temperature of MP was not changed during catalytic thermogravimetric analysis over both catalysts, that of HDPE was reduced from 465 °C to 379 °C over HY and to 393 °C over HZSM-5 because of their catalytic effects. When HDPE was co-pyrolyzed with MP over the catalysts, the catalytic decomposition temperatures of HDPE were increased to 402 °C over HY and 408 °C over HZSM-5. The pyrolyzer-gas chromatography/mass spectrometry results showed that the main pyrolyzates of MP and HDPE, which comprised a large amount of oxygenates and aliphatic hydrocarbons with a wide carbon range, were converted efficiently to aromatics using HY and HZSM-5. Although HY can provide easier diffusion of the reactants to the catalyst pore and a larger amount of acid sites than ...

Polyvinyl acetate (PVAc) is used in various adhesive, paint, and transparent tape applications. It is also used as a food additive in food manufacturing to make chewing gum and fruit and vegetable glazes; however, guidelines on the amount of food additives that is used have not yet been established. In this study, a method was developed for analysis of polyvinyl acetate (PVAc) using high-performance liquid chromatography with an evaporative light scattering detector (HPLC–ELSD) and pyrolyzer–gas chromatography–mass spectrometry (Py–GC–MS). The analytical methods were applied to commercially available chewing gum. In the HPLC–ELSD analysis, the linearity was acceptable (R2 > 0.999), and the limits of detection and quantification were 22.2 and 67.3 µg/mL, respectively. The accuracies of PVAc were 87–115% at spike levels of 200–1000 µg/mL for the intra- and inter-day tests. The contents of PVAc in the chewing gum samples were n.d. (not detected)—13.8 g/kg. The presence of PVAc in ch...

In this study, shrimp shell powder, prepared by treating shrimp-processing waste by boiling and crushing, was used as a substrate for isolation of chitinase-producing microorganism. These organisms may have an important economic role in the biological control of rice and other fungal pathogens. Two hundred strains of bacteria with the ability to degrade chitin from shrimp shell waste were isolated from paddy soil, and of these, 40 strains showed chitinase activity in a solid state cultivation. One of the most potent isolates (strain R 176) was identified as Bacillus thuringiensis. Identification was carried out using morphological and biochemical properties along with 16S rRNA sequence analysis. This strain was able to produce high levels of extracellular chitinase in solid media containing shrimp shells as sole carbon source [1.36 U/g initial dry substrate (IDS)], which was 0.36-fold higher than the productivity in a liquid culture with colloidal chitin. The effects of medium composition and physical parameters on chitinase production by this organism were studied. The optimal medium contained shrimp shell mixed with rice straw in 1:1 ratio added with ball-milled chitin 0.5 % (w/v) and ammonium sulfate 0.5 % (w/v). The highest enzyme production (3.86 U/g IDS) by B. thuringiensis R 176 was obtained at pH 7, 37 °C after 14 days growth. With respect to the high amount of chitinase production by this strain in a simple medium, this strain could be a suitable candidate for the production of chitinase from chitinous solid substrates, and further investigations into its structure and characteristics are merited.

A new accurate, specific, precise, acetonitrile-free and cost-effective high performance liquid chromatographic method has been developed and validated for the determination of montelukast in bulk and in its pharmaceutical dosage forms of tablet and suspension. Methanol: D.I water adjusted to pH 2.8 ± 0.1 was used as the mobile phase at a flow rate of 1.0 ml/min using a Symmetry C18 column. The effluent was spectrophotometrically monitored at 220 nm. The intraday and inter-day precisions showed coefficients of variation ranging from 0.54% to 1.14% at three concentrations. The calibration curve was linear with a correlation coefficient of 0.999979. The averages of the absolute and relative recoveries were found to be 98.78 to 99.25%. The proposed HPLC method was successfully applied to quantify the amount of montelukast in bulk and two dosage forms in quality control.

The emphasis of this study was on the sensitivity of the antibiotics to pathogenic bacterial strains of methicillin resistant Staphylococcus aureus (MRSA). Total of 280 samples were collected in microbiology laboratory of Sheikh Zayed Hospital, Lahore. Staphyloccus aureus was isolated by using Blood agar, Nutrient agar, Mannitol salt agar, Catalase, Coagulase and Dnase tests. Anti PBP-2a latex agglutination test was used to identify MRSA. Out of 139 Staphylococcus aureus strains isolated from various clinical samples, 43.16% were found to be methicillin resistant. The efficacies of these isolates were tested by paper disc diffusion method on Mueller Hinton agar. All MRSA isolates were resistant to penicillin. Among MRSA isolates, 44.82% were from different inpatient departments, whereas, 40.43% of the MRSA isolates were from outpatients. This preliminary report showed a high prevalence of MRSA in the hospital. To reduce the prevalence of MRSA, regular surveillance of hospital acquired infections is the need of the hour. Keywords: Methicillin resistant, Staphylococcus aureus, Anti PBP-2a, latex agglutination test, Paper disc diffusion method

Multidrug resistance is a condition or status of a micro-organism that facilitate or enable the organism to not only act as pathogen but also to resist against distinct chemicals of a wide variety of structure and function targeted to eradicate the organism such as antibiotics antiviral medications, antiparasitic drugs, and antifungal drugs etc. Based on degree of resistance different types of MDR can be categorized such as extensively-drug resistant (XDR) and pandrug-resistant (PDR). The explanations of such terminologies were published and are openly accessible in a journal called "Clinical Microbiology and Infection".

The medicinal and preservative uses of clove (syzygium aromaticum) have been claimed for centuries and it was valued by the people of ancient times for its beneficial health effects. This study was conducted to evaluate the antibacterial activity of aqueous extract of clove against clinical and foodborne isolates. In vitro antibacterial activity of different concentrations (40, 35, 30, 25, 20, 15, 10 and 5%) ranged from 400 mg/ml to 50mg/ml of aqueous extract of clove was investigated against five clinical isolates including Escherichia coli,
Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi and Streptococcus pyogenes and one foodborne isolate Salmonella enterica ATCC 14028. Agar well diffusion assay and filter paper disk diffusion assay were used to determine the growth inhibition. MICs and MBCs/MLCs were evaluated by broth dilution method. Antibiotic susceptibility testing was performed by Kirby-Bauer Disk Diffusion Susceptibility Test. The aqueous extract of clove exhibited strong inhibition against S. enterica ATCC 14028, E. coli , K. pneumoniae, P.
aeruginosa, S. typhi and S. pyogenes. The maximum diameters of zones of inhibition that were measured ranged between 23-20 mm/100 μl in well diffusion assay and 12-11 mm/10 μl in filter paper disk diffusion assay for 40% (400 mg/ml) concentration of aqueous extract. The minimum concentration of extract that checked for
growth inhibition was 50 mg/ml and was inhibitory and effective in well diffusion assay. The MBC of clove extract was found to be 40 mg/ml for P. aeruginosa, 70 mg/ml for S. typhi, 80 mg/ml for S. enterica ATCC 14028 and E. coli and 90 mg/ml for S. pyogenes. The MICs were also recorded. In conclusion, since the aqueous extract of clove has bacteriostatic and bactericidal activity against all test isolates that were resistant against various antibiotics tested, so its effective use can be made in therapy for infections caused by these organisms as
in recent years multidrug resistance has emerged among pathogenic bacteria against antibiotic therapy. Moreover, as spice extract showed remarkable activity against S. enterica atcc 14028 and E. coli which are pathogenic and important food spoilage causing organisms so it may also provide an alternative to conventional antibacterial food additives.

E.cli (Uropathogn) on agar medium showing resistance to different antibiotics applied. Multidrug resistance is a condition or status of a microorganism that facilitate or enable the organism to not only act as pathogen but also to resist against distinct chemicals of a wide variety of structure and function targeted to eradicate the organism such as antibiotics antiviral medications, antiparasitic drugs, and antifungal drugs etc. Based on degree of resistance different types of MDR can be categorized such as extensively-drug resistant (XDR) and pandrug-resistant (PDR). The explanations of such terminologies were published and are openly accessible in a journal called "Clinical Microbiology and Infection".