Biologically Active C-Alkylated Flavonoids from Dodonaea viscosa

Akhtar Muhammad,Itrat Anis,Ajmal Khan,Bishnu P. Marasini,Muhammad Iqbal Choudhary,Muhammad Raza Shah 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.3

A new C-alkylated flavonoid (5,7-dihydroxy-3'-(4''-acetoxy-3''-methylbutyl)-3,6,4'-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3'-(3-hydroxymethylbutyl)-3,6,4'-trimethoxyflavone (2), 5,7,4'-trihydroxy-3'-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-3,6,4'-trimethoxyflavone (4), 5,7,4'-trihydroxy-3,6-dimethoxy-3'-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1-5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin.

In vitro Study on the Antimicrobial Activity of Human Tears with Respect to Age

( Muhammad Zahoor ),( Haji Bahadar ),( Muhammad Ayaz ),( Ajmal Khan ),( Muhammad Jalat Shah ) 대한임상검사과학회 2018 대한임상검사과학회지(KJCLS) Vol.50 No.2

Lysozyme is present in tears and has the ability to inhibit bacterial growth. In addition, it acts as a physiological scavenger for harmful substances. In the present study, sixteen tear samples from people of different ages were evaluated for their antibacterial spectrum against selected bacterial strains (Escherichia coli, Shigella sonnei, Staphylococcus aureus, Salmonella enterica Typhi). A radial diffusion assay was used to evaluate the antibacterial potential of tear samples. To correlate the antibacterial activities of these tear samples, the concentration of lysozyme in the tear samples was also determined. Ampicillin was used as a standard drug. The zone of inhibition (mm) was used to measure the antibacterial property of the tears. All samples showed good antibacterial activities. The tear samples of children showed antibacterial activities in the range of 4.40∼5.00 mm inhibition zones against the selected bacterial strains. The tear samples from the young and adults showed good antibacterial potential with a zone of inhibition in the range of 3.20∼4.00 and 4.00∼5.50 mm, respectively. The tear samples from the old age group showed inhibition zones from 1.50∼5 mm. The adult tear samples showed the maximum inhibition against the selected bacterial strains among all groups. The lysozyme concentration was 1.7 mg/mL, 1.95 mg/mL, 2.13 mg/mL, and 1.76 mg/mL for children, young, adults, and elderly, respectively. In conclusion, the tears from adults have the high inhibition potential. In addition, this data also showed that the lysozyme contents in the tear sample increased with age until 40∼42 years.

In vitro Study on the Antimicrobial Activity of Human Tears with Respect to Age

Zahoor, Muhammad,Bahadar, Haji,Ayaz, Muhammad,Khan, Ajmal,Shah, Muhammad Jalat Korean Society for Clinical Laboratory Science 2018 대한임상검사과학회지(KJCLS) Vol.50 No.2

Lysozyme is present in tears and has the ability to inhibit bacterial growth. In addition, it acts as a physiological scavenger for harmful substances. In the present study, sixteen tear samples from people of different ages were evaluated for their antibacterial spectrum against selected bacterial strains (Escherichia coli, Shigella sonnei, Staphylococcus aureus, Salmonella enterica Typhi). A radial diffusion assay was used to evaluate the antibacterial potential of tear samples. To correlate the antibacterial activities of these tear samples, the concentration of lysozyme in the tear samples was also determined. Ampicillin was used as a standard drug. The zone of inhibition (mm) was used to measure the antibacterial property of the tears. All samples showed good antibacterial activities. The tear samples of children showed antibacterial activities in the range of 4.40~5.00 mm inhibition zones against the selected bacterial strains. The tear samples from the young and adults showed good antibacterial potential with a zone of inhibition in the range of 3.20~4.00 and 4.00~5.50 mm, respectively. The tear samples from the old age group showed inhibition zones from 1.50~5 mm. The adult tear samples showed the maximum inhibition against the selected bacterial strains among all groups. The lysozyme concentration was 1.7 mg/mL, 1.95 mg/mL, 2.13 mg/mL, and 1.76 mg/mL for children, young, adults, and elderly, respectively. In conclusion, the tears from adults have the high inhibition potential. In addition, this data also showed that the lysozyme contents in the tear sample increased with age until 40~42 years.

Study of an improved and novel venturi scrubber configuration for removal of radioactive gases from NPP containment air during severe accident

Farooq Mujahid,Ahmed Ammar,Qureshi Kamran,Shah Ajmal,Waheed Khalid,Siddique Waseem,Irfan Naseem,Ahmad Masroor,Farooq Amjad 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.9

Owing to the rising concerns about the safety of nuclear power plants (NPP), it is essential to study the venturi scrubber in detail, which is a key component of the filtered containment venting system (FCVS). FCVS alleviates the pressurein containment byfiltering and venting out the contaminated air. Themain objective of this research was to perform a CFD investigation of different configurations of a circular, non-submerged, selfpriming venturi scrubber to estimate and improve the performance in the removal of elemental iodine from the air. For benchmarking, a mass transfer model which is based on two-film theory was selected and validated by experimental data where an alkaline solution was considered as the scrubbing solution. This mass transfer model was modified and implemented on a unique formation of two self-priming venturi scrubbers in series. Euler-Euler method was used for two-phase modeling and the realizable K ε model was used for capturing the turbulence. The obtained results showed a remarkable improvement in the removal of radioactive iodine from the air using a series combination of venturi scrubbers. The removal efficiency was improved at every single data point.

Investigation of dust particle removal effi ciency of self-priming venturi scrubber using computational fl uid dynamics

Sarim Ahmed,Hassan Mohsin,Kamran Qureshi,Ajmal Shah,Waseem Siddique,Khalid Waheed,Naseem Irfan,Masroor Ahmad,Amjad Farooq 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.5

A venturi scrubber is an important element of Filtered Containment Venting System (FCVS) for theremoval of aerosols in contaminated air. The present work involves computational fluid dynamics(CFD) study of dust particle removal efficiency of a venturi scrubber operating in self-priming mode usingANSYS CFX. Titanium oxide (TiO2) particles having sizes of 1 micron have been taken as dust particles. CFD methodology to simulate the venturi scrubber has been first developed. The cascade atomizationand breakup (CAB) model has been used to predict deformation of water droplets, whereas the EulerianeLagrangian approach has been used to handle multiphase flow involving air, dust, and water. Thedeveloped methodology has been applied to simulate venturi scrubber geometry taken from the literature. Dust particle removal efficiency has been calculated for forced feed operation of venturi scrubberand found to be in good agreement with the results available in the literature. In the second part, venturiscrubber along with a tank has been modeled in CFX, and transient simulations have been performed tostudy self-priming phenomenon. Self-priming has been observed by plotting the velocity vector fields ofwater. Suction of water in the venturi scrubber occurred due to the difference between static pressure inthe venturi scrubber and the hydrostatic pressure of water inside the tank. Dust particle removal efficiencyhas been calculated for inlet air velocities of 1 m/s and 3 m/s. It has been observed that removalefficiency is higher in case of higher inlet air velocity.

Silver and palladium nanoparticle embedded poly(n-isopropylacrylamide-co-2- acrylamido-2-methylpropane sulfonic acid) hybrid microgel catalyst with pH and temperature dependent catalytic activity

Abdul Haleem,Sidra Bibi Syaal,Muhammad Ajmal,Jaweria Ambreen,Sajid Rauf,Nasir Ali,Saz Muhammad,Afzal Shah,Muhammad Abid Zia,Muhammad Siddiq 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.4

Here in, we demonstrate facile fabrication of silver and palladium nanoparticles in dual responsive poly(Nisopropylacrylamide- co-2-Acrylamido-2-methylpropane sulfonic acid) microgel with temperature- and pH-dependent catalytic potential. Palladium-based catalyst showed better catalytic efficiency as compared to silver-based catalyst for degradation of Rhodamine-B and P-Nitrophenol in aqueous medium under the same set of reaction conditions. The responsive nature of the microgel was found to be useful to tune the catalytic activity of the as-prepared catalysts, and reduction rate was enhanced with the pH and temperature elevation of the reaction medium; however, the increasing trend was slowed in the volume phase transition region of the microgel. Under a specific set of reaction conditions, the reduction of Rhodamine-B was as fast as 0.968 and 0.571 min1 when catalyzed with palladium and silver based catalysts, respectively. The hydrodynamic radius of the particles of microgel support was found to be in the range of 65- 180 nm when pH and temperature of the medium were varied in the range of 2-12 and 25-45, respectively. The estimated diameter of silver and palladium nanoparticles fabricated in the microgel support under the same set of reaction conditions was 9-15 and 7-11 nm, respectively.

Flow characteristics within the wall boundary layers of swirling steam flow in a pipe comprising horizontal and inclined sections

Afrasyab Khan,Mohd Sobri Takriff,Masli Irwan Rosli,Nur Tantiyani Ali Othman,Khairuddin Sanaullah,Andrew Ragai Henry Rigit,Ajmal Shah,Atta Ullah 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.1

Handling and utilization of steam flow efficiently to obtain various tangible industrial outcomes relies mainly upon how to optimize various flow parameters like boundary layer thickness, skewness, shear stress, and turbulent dissipation for minimum losses such as pressure and heat. Swirling steam flow, driven by a propeller through a circular duct along horizontal and inclined surfaces presents an interesting flow regime that includes the boundary layer flows close to the wall of the pipe and weak and uniform flow that prevails across the inner region of the pipe. Such flow was investigated here with a specially designed experimental facility. Convective Instabilities were observed that propagate along the axial direction in a nonlinear fashion. It was observed that the operating conditions could be optimized for measuring the shear stresses based on the intersection of the profiles under the effect of variations in the inlet pressure of steam and the rotational speed of the propeller. We found that the flow transformed from positive to negative skewness when the rotational speed of the propeller was raised from 4-14 thousand per minute at 10 bars of constant inlet steam pressure. More area came under the effect of reduced skin friction when the rotational speed of the propeller was raised. More turbulent energy was found to be dissipated when the rotational speed of the propeller was raised. It was found that yet the dissipation of the turbulent energy takes place under the joint effect of inlet pressure of steam and the rotational speed of the propeller, but the exact effect of any one of these two operating parameters still needs to be determined and requires further investigation.