Chemical composition and anti-fungal properties of the essential oils and crude extracts of Orthosiphon stamineus Benth

Hossain, M.A.,Ismail, Z.,Rahman, A.,Kang, S.C. Elsevier 2008 Industrial crops and products Vol.27 No.3

The hydrodistilled essential leaves and stems oils of Orthosiphon stamineus Benth were analysed by GC-MS/MS. Sixty nine compounds representing 97.6 and 97.4% of the total leaves and stems oils, respectively were identified, of which β-caryophyllene (24.0 and 35.1%), α-humulene (14.2 and 18.4%), β-elemene (11.1 and 8.5%), 1-octen-3-ol (8.2 and 7.0%), β-bourbonene (3.4 and 3.0%), β-pinene (2.1 and 1.7%), caryophyllene oxide (1.6 and 2.2%), camphene (1.6 and 1.3%) and limonene (1.2 and 1.1%) were the major compounds. Thus, the monoterpenes and sesquiterpenes were the predominant portions of the oils. Essential oils and methanol extract of O. stamineus and the derived fractions of hexane, chloroform, and ethyl acetate were tested for anti-fungal activity, which was determined by disc diffusion and minimum inhibitory concentration (MIC) determination methods. The oils, methanol extract and derived fractions of methanol extract displayed great potential of anti-fungal activity as a mycelial growth inhibitor against the tested phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium solani, Colletotricum capsici and Phytophthora capsici, in the range of 49.3-70.3% and minimum inhibitory concentration ranging from 500 to 1000μg/ml.

Synthesis and analysis of the influence of Eu3+ on the structural, ferromagnetic, dielectric and conductive characteristics of Ni0.4Zn0.45Cu0.15Fe(2-x)EuxO4 composites using conventional double sintering ceramic method

I. N. Esha,Md. Al-Amin,F. T. Z. Toma,Enayet Hossain,M. N. I. Khan,Kazi Hanium Maria 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.5

Conventional double sintering ceramic method has been followed to prepare a series of Eu substituted Ni0.4Zn0.45Cu0.15Fe(2-x) EuxO4 (NZCFEO) ferrites with x = 0.00, 0.02, 0.04, 0.07, 0.10, 0.12, 0.15. X-ray diffraction peaks confirm the single phase cubic spinel structures of all the samples. The lattice parameter is found to be distorted with the addition of Eu into the samples. X-ray density and bulk density increase with the increase of Eu content. Better crystallization has been obtained with the decreasing porosity as a result of increasing Eu3+ concentration. The dielectric constant of the samples shows a decreasing trend while both AC and DC resistivities are observed to increase with the increase of Eu3+ concentration. The high resistivity offers greater value of the activation energy. Permeability is found to decrease with increasing Eu content. Saturation magnetization changed significantly with Eu3+ concentration. Noteworthy decrease of the Curie temperature is observed with the addition of Eu substituent.

Spectroscopic and cloud point studies of the interaction and thermodynamics of ciprofloxacin hydrochloride+surfactants mixture in different solvents: Effect of temperature and composition

Md. Anamul Hoque,Md. Mofaqkharur Rahman,Shamim Mahbub,Mezbah Hossain,Mohammed Abdullah Khan,Md. Ruhul Amin,Ali S. Alqahtani,Mohammad Z. Ahmed,Mohammed S. Alqahtani,Omar M. Almarfadi 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.7

Surfactant is one of the most important chemical entities in drug formulation which can bind with drug molecules. Herein, the binding interaction of ciprofloxacin hydrochloride (CFH) drug with two different surfactants (sodium dodecyl sulfate (SDS) and Triton X-100 (TX-100)) has been investigated through UV-Visible spectroscopic and cloud point measurement techniques at different conditions. The absorption spectrum of CFH was found to be dependent on presence of additives/temperature change. The binding constant (Kb) of CFH+SDS/CFH+TX-100 was found to be increased primarily, reached a maximum value and then decreased with the increase of temperature, except in water medium (pH=2.0) and 30% (v/v) methanol. The Kb values for CFH+SDS were found to be higher in the aqueous medium than almost all medium studied herein, while better binding was observed in the alcoholic medium in the case of the CFH+TX-100 system. The Gibbs free energy of binding (Gb o) for both CFH+SDS and CFH+TX- 100 systems were attained negative in each case studied, inferring the spontaneous binding phenomenon. The cloud point (CP) value of CFH+TX-100 mixture was lessened in ZnSO4·7H2O solution and the CP values exhibited a gradual reduction through the upsurge of electrolyte concentration. The positive values of the Gibbs free energy of clouding indicated the nonspontaneous clouding phenomena. To disclose the interaction between drug and surfactant, other thermodynamic parameters, e.g., enthalpy (Hb o) and entropy (Sb o), different transfer energies as well as entropyenthalpy compensation parameters of binding/clouding were evaluated and clarified with proper explanation.

The presence of carcinogenic radon in the Padma River water, adjacent to the Rooppur Nuclear Power Plant

Siraz M.M. Mahfuz,Alam M.S.,Jubair A.M.,Das S.C.,Ferdous J.,Hossain Z.,Das S.,Khandaker Mayeen Uddin,Bradley D.A.,Tokonami Shinji,Yeasmin S. 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.8

Radon is a naturally occurring carcinogenic agent, poses a serious health hazard when inhaled or ingested in significant amounts. The water of the Padma river will be used as a tertiary coolant for the soon-to-be-commissioned ‘Rooppur Nuclear Power Plant’. Hence, it is important to assess the radiological status of the river prior to the commission of this power plant. Therefore, for the first time, 25 samples of water were collected from various locations of the Padma River and analyzed for radon concentration using the RAD H2O (DURRIDGE) radon monitoring device. The radon concentrations were found in the range from 0.077 ± 0.036 to 0.494 ± 0.211 Bq/L with a mean of 0.250 ± 0.093 Bq/L. All the concentrations were found to be below the recommended limits of WHO (100 Bq/L) and USEPA (11.1 Bq/ L). The mean annual effective dose due to the radon exposure via inhalation and ingestion pathways were 0.638 mSv/y and 0.629 mSv/y, respectively, which were all well below the annual effective dose recommended by WHO (0.1 mSv/y). Since Bangladesh lacks a national safety limit of radon in water, this pioneering study provides baseline data on radon levels for the environment around Rooppur Nuclear Power Plant.

Evaluation of a Typhoid/Paratyphoid Diagnostic Assay (TPTest) Detecting Anti- <i>Salmonella</i> IgA in Secretions of Peripheral Blood Lymphocytes in Patients in Dhaka, Bangladesh

Khanam, Farhana,Sheikh, Alaullah,Sayeed, Md. Abu,Bhuiyan, Md. Saruar,Choudhury, Feroza Kaneez,Salma, Umme,Pervin, Shahnaz,Sultana, Tania,Ahmed, Dilruba,Goswami, Doli,Hossain, Md. Lokman,Mamun, K. Z.,C Public Library of Science 2013 PLoS neglected tropical diseases Vol.7 No.7

<▼1><P><B>Background</B></P><P>Rapid and reliable diagnostic assays for enteric (typhoid and paratyphoid) fever are urgently needed. We report the characterization of novel approach utilizing lymphocyte secretions, for diagnosing patients with enteric fever by the TPTest procedure.</P><P><B>Methodology</B></P><P>TPTest detects <I>Salmonella</I>-specific IgA responses in lymphocyte culture supernatant. We utilized TPTest in patients with suspected enteric fever, patients with other illnesses, and healthy controls. We also evaluated simplified modifications of TPTest for adaptation in laboratories with limited facilities and equipment.</P><P><B>Principal Findings</B></P><P>TPTest was positive in 39 (27 typhoid and 12 paratyphoid A) patients confirmed by blood culture and was negative in 74 healthy individuals. Among 32 individuals with other illnesses, 29 were negative by TPTest. Of 204 individuals with suspected enteric fever who were negative by blood culture, 44 were positive by TPTest and the patients were clinically indistinguishable from patients with confirmed bacteremia, except they were more likely to be under 5 years of age. We evaluated simplifications in TPTest, including showing that lymphocytes could be recovered using lysis buffer or buffy coat method as opposed to centrifugation, that incubation of cells at 37°C did not require supplemental CO<SUB>2</SUB>, and that results were available for majority of samples within 24 hours. Positive results by TPTest are transient and revert to negative during convalescence, supporting use of the test in endemic areas. The results can also be read using immunodot blot approach as opposed to ELISA. Since no true gold standard currently exists, we used a number of definitions of true positives and negatives. TPTest had sensitivity of 100% compared to blood culture, and specificity that ranged from 78–97% (73–100, 95% CI), depending on definition of true negative.</P><P><B>Conclusion</B></P><P>The TPTest is useful for identification of patients with enteric fever in an endemic area, and additional development of simplified TPTest is warranted.</P></▼1><▼2><P><B>Author Summary</B></P><P><I>Salmonella enterica</I> serotype Typhi and Paratyphi A are responsible for typhoid and paratyphoid fever respectively and the disease caused is known generally as enteric fever. Appropriate and early diagnosis of the disease is important for initiation of treatment of the patient with a suitable antibiotic. The performance of the available diagnostic methods take time and as well as have low sensitivity and specificity. We describe here an immunodiagnostic assay, the TPTest, which is based on the use of secretions of antibodies from peripheral blood lymphocytes. We describe simplifications of the procedure and show that the assay has as a sensitivity of 100% with a specificity that ranges from 78–97% (73–100, 95% CI) for detecting patients with typhoid and paratyphoid fever in an enteric fever endemic zone. The TPTest uses a small blood volume, and reverts to negative by convalescence, supporting its further development as a relatively low cost assay to diagnose patients with enteric fever in endemic zones.</P></▼2>