Potential antifilarial activity of the fruit, leaf and stem extract of Melia azedarach Linn. on cattle filarial parasite Setaria cervi in vitro

Ahmed, Qamar U.,Zaidi, S.M.K.R.,Kaleem, M.,Khan, N.U.,Singhal, K.C. Kyung Hee Oriental Medicine Research Center 2006 Oriental pharmacy and experimental medicine Vol.6 No.2

The effect of aqueous and alcoholic extracts of the fruit, leaf and stem of Melia azedarach Linn. (Meliaceae) on the spontaneous movements of both the whole worm and the nerve-muscle (n.m.) preparation of Setaria (S.) cervi and on the survival of microfilariae in vitro was studied. Alcoholic extracts of fruit, leaf and stem caused inhibition of the spontaneous movements of the whole worm and the n.m. preparation of S. cervi, while only aqueous extract of fruit caused inhibition of the spontaneous movements of the whole worm and the n.m. preparation of S. cervi. The initial stimulatory effect was not observed by the aqueous and alcoholic extracts of fruit on n.m. preparation. The concentrations required to inhibit the movements of the whole worm and n.m. preparation for alcoholic extracts of fruit, leaf and stem were 250, $40\;{\mu}g/ml$; 280, $40\;{\mu}g/ml$ and 270, $25\;{\mu}g/ml$ respectively, whereas an aqueous extract of fruit caused inhibition of whole worm and n.m. preparation at $200\;{\mu}g/ml$ and $40\;{\mu}g/ml$ respectively. Alcoholic extracts of the fruit, leaf and stem and aqueous extract of the fruit of M. azedarach caused concentration related inhibition on the survival of microfilariae (m.f.) of S. cervi. The $LC_{50}$ and $LC_{90}$ as observed after 6 h were found to be 5, 15, 10, 20 ng/ml and 10, 25, 20 and 35 ng/ml, respectively. This work was conducted in view of the exploration of potential antifilarial herbal drug.

Momordica charantia and Allium sativum : Broad Spectrum Antibacterial Activity

Khan, M.R.,Omoloso, A.D. The Korean Society of Pharmacognosy 1998 생약학회지 Vol.29 No.3

In the Asian sub-continent Momordica charantia and Allium sativum are extensively used as food and are popular in herbal medicine. The two were screened against 15 pathogens and both exhibited broard spectrum antimicrobial activity. As compared to the standard antibiotics, M. charantia demonstrated broader and higher level of activity against most of the organisms. On the other hand A. sativum showed comparable activity to the standard antibiotics. Both M. Charantia and A. sativum are proposed as non toxic, safe, broad spectrum antibacterial agents.

Quorum sensing activity of the plant growth-promoting rhizobacterium Serratia glossinae GS2 isolated from the sesame (Sesamum indicum L.) rhizosphere

Jung, B. K.,Khan, A. R.,Hong, S. J.,Park, G. S.,Park, Y. J.,Kim, H. J.,Jeon, H. J.,Khan, M. A.,Waqas, M.,Lee, I. J. UNIV. OF MILAN DEPARTMENT OF FOOD SCIENCE AND MICR 2017 ANNALS OF MICROBIOLOGY Vol.67 No.9

<P>Plant growth-promoting rhizobacteria (PGPR) affect plant growth through various mechanisms, such as indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and biofilm formation. The aim of the study reported here was to isolate and characterize rhizobacteria that produce quorum-sensing signal molecules and other PGPR-related molecules. A biofilm-forming bacterium, GS2, was isolated from the rhizosphere of a sesame plant and subsequently found to produce two quorum-sensing signal molecules that were identified as N-hexanoyl-L-homoserine lactone (m/z 200) and N-octanoyl-L-homoserine lactone (m/z 228) by liquid chromatography-tandem mass spectrometry analysis. The strain was also found to produce IAA (17.2 mu g mL(-1)), gibberellins (113.7 mu g mL(-1)), and ACC deaminase (9.7 mu M alpha-ketobutyrate mg(-1) protein h(-1)). The strain was identified as Serratia glossinae based on a comparison of 16S rRNA gene sequences. Inoculation of the strain promoted growth of a gibberellin-deficient rice dwarf mutant (Waito-C). Different growth attributes, including shoot and root elongation, chlorophyll content, and plant weight could be attributed to the PGPR characteristics of strain GS2. These results suggest that S. glossinae strain GS2 can serve as a microbial agent that improves plant growth.</P>

<i>N6</i>-methyladenosine modification of hepatitis B virus RNA differentially regulates the viral life cycle

Imam, Hasan,Khan, Mohsin,Gokhale, Nandan S.,McIntyre, Alexa B. R.,Kim, Geon-Woo,Jang, Jae Young,Kim, Seong-Jun,Mason, Christopher E.,Horner, Stacy M.,Siddiqui, Aleem National Academy of Sciences 2018 Proceedings of the National Academy of Sciences Vol.115 No.35

<P>N6-methyladenosine (m(6)A) RNA methylation is the most abundant epitranscriptomic modification of eukaryotic messenger RNAs (mRNAs). Previous reports have found m(6)A on both cellular and viral transcripts and defined its role in regulating numerous biological processes, including viral infection. Here, we show that m(6)A and its associated machinery regulate the life cycle of hepatitis B virus (HBV). HBV is a DNA virus that completes its life cycle via an RNA intermediate, termed pregenomic RNA (pgRNA). Silencing of enzymes that catalyze the addition of m(6)A to RNA resulted in increased HBV protein expression, but overall reduced reverse transcription of the pgRNA. We mapped the m(6)A site in the HBV RNA and found that a conserved m(6)A consensus motif situated within the epsilon stem loop structure, is the site for m(6)A modification. The epsilon stem loop is located in the 3' terminus of all HBV mRNAs and at both the 5' and 3' termini of the pgRNA. Mutational analysis of the identified m(6)A site in the 5' epsilon stem loop of pgRNA revealed that m(6)A at this site is required for efficient reverse transcription of pgRNA, while m(6)A methylation of the 3' epsilon stem loop results in destabilization of all HBV transcripts, suggesting that m(6)A has dual regulatory function for HBV RNA. Overall, this study reveals molecular insights into how m(6)A regulates HBV gene expression and reverse transcription, leading to an increased level of understanding of the HBV life cycle.</P>

A non-catalytic, supercritical methanol route for effective deacidification of naphthenic acids

Khan, M.K.,Insyani, R.,Lee, J.,Yi, M.,Lee, J.W.,Kim, J. Butterworths [etc.] ; Elsevier Science Ltd 2016 Fuel Vol.182 No.-

High acid crudes contain large amounts of naphthenic acids (NAs), which lead to severe corrosion in oil refinery equipment and serious environmental problems. The goal of this study is to develop a non-catalytic supercritical methanol (scMeOH) route for effective deacidification of NA mixtures and high acid crudes (Laguna and Bachaquero-13). Various reaction parameters, including temperature, pressure, reaction time, and NA-to-methanol ratio, are explored to find effective reaction conditions for reducing the total acid number (TAN) of the mixtures. Almost complete TAN reduction of naphthenic acid (96.9%) is achieved at 400<SUP>o</SUP>C, 10MPa, and 3h. The reaction in scMeOH at 400<SUP>o</SUP>C, 30MPa and 1h is effective in the TAN reaction of high acid crudes (93.6-94.0%). The chemical composition of the liquid products obtained under the different reaction conditions, analyzed using gas chromatography-mass spectroscopy, show that esters are the most abundant species, indicating that esterification with scMeOH is the major reaction pathway. The most recalcitrant NA species, which remained after the reaction, are found to be 2-ethyl-2,3,3-trimethyl-butanoic acid and 2,3-dimethyl-2-(1-methylethyl)-butanoic acid. This is attributed to the branched hydrocarbons located near the carboxylic acid groups, which hinder the access of methanol molecules.

Electrospun Nanofibers: Preparation, Characterization and Atmospheric Fog Capturing Capabilities

M. A. Alamir,I. M. Alarifi,W. A. Khan,W. S. Khan,R. Asmatulu 한국섬유공학회 2019 Fibers and polymers Vol.20 No.10

This study was aimed at enhancing the capability of electrospun nanofiber mats to convert atmospheric fog intofresh water effectively. The demand for clean water has been increasing worldwide, and this problem can be addressedeconomically by utilizing new technologies. It is known that atmospheric fresh water found on the earth is about 0.03 % ofthe total global fresh water, which is more than enough to meet the demand for fresh water in many locations. Althoughdesalination may produce a significant quantity of fresh water, it is a fairly costly, energy-intensive, and time-consumingprocess. In this research, the electrospinning method was used to fabricate superhydrophilic polyacrylonitrile (PAN) andpolyvinyl chloride (PVC) nanofiber mats incorporated with hydrophilic polymers of polyvinylpyrrolidone (PVP),polyethylene glycol (PEG), and chitosan at various direct current (DC) voltages, pump speeds, and tip-to-collector distances,in order to evaluate their capability of capturing fresh water from atmospheric fog. Fourier transform infrared (FTIR) andRaman spectroscopy were used to characterize the chemical structures of the nanofibers, while scanning electron microscopy(SEM) and water contact angle measurement methods were used to determine the morphology and surface hydrophobicity,respectively, of the produced nanofibers. At higher concentrations of PVP, PEG, and chitosan (e.g., 16 and 32 wt%), most ofthe electrospun nanofibers were superhydrophilic, with water contact angle values less than 5 o in 0.5 seconds. Humidifierand humidity test chamber results indicated that superhydrophilic nanofibers could absorb up to 69 % of their weight in ashorter period of time. This scalable process can be extended to capturing a larger quantity of fresh water from theatmosphere.

Filler Effect of Pozzolanic Materials on the Strength and Microstructure Development of Mortar

M. N. N. Khan,M. Jamil,M. R. Karim,M. F. M. Zain,A. B. M. A. Kaish 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.1

The utilization of pozzolans in cementitious system (concrete and mortar) minimizes both cost and energy. It also enhances mechanical strength and durability of the system. The total contribution of pozzolans can be categorized into two: (i) physical or filler effect which is attributed by the fineness of the particles and (ii) chemical or pozzolanic effect which is attributed by the pozzolanic reaction. It is difficult to quantify the strength development of cementitious system caused by the filler and pozzolanic effect separately. Therefore, the individual contribution of pozzolans in cementitious system because of its physical and chemical effects need to be profoundly understood by the scientific community. This paper reviews available literatures to understand the effect of non-reactive fillers that attributed as the microfiller effect of pozzolans in cementitious systems. The previous studies utilized chemically inactive materials that attributed only the microfiller activity of pozzolans for a partial replacement of cement. It was reported that filler effect is equal or sometimes more significant than pozzolanic effect in concrete. A larger range of replacement percentages (like 5%, 10%, 15% or 10%, 20%, 30% etc.) was used in the previous studies. However, probabilities of the optimum compressive strength because of the filler effect may lie in between two larger range of replacement percentages. Therefore, an experimental work is also carried out using natural ground sand of size 7.6-μm at a lower range of cement replacement percentages (like 2.5%, 5%, 7.5% etc.) in mortar. Compressive strength of mortar at different ages and microstructure analysis of mortar at 28 days were performed in this study. Test results showed that the filler effect is more pronounced at a lower replacement percentages of cement (0-10%) while using smaller non-reactive fillers. The maximum strength due to filler effect of ground sand is acheieved at 7.5% replacement of cement. Scanning Electron Microscope (SEM) images also confirmed the effect of fillers on the microstructure development of mortar.

Broad Spectruc Anti-bacterial Activity of the Leaves , Stem and Root Barks of Myristica subabulata

M. R. Khan,M. Kihara,A. D. Omoloso 한국생약학회 2001 Natural Product Sciences Vol.7 No.1

A number of Myristica species are used in herbal medicine for a variety of ailments. The methanol extracts of the leaves and the stem and root barks of Myristica subabulata were fractionated into petrol, dichloromethane and finally ethyl acetate. These were then screened against a total of 31 micro-organisms comprising of 13 G +ve, 12 G ve, one protozoa and 5 moulds. A broad-spectrum antibacterial activity was observed. As compared to fractionated the un-fractionated extracts exhibited much better level of activity.

Effect of Al-doping on optical and electrical properties of spray pyrolytic nano-crystalline CdO thin films

M.K.R. Khan,M. Azizar Rahman,M. Shahjahan,M. Mozibur Rahman,M.A. Hakim,Dilip Kumar Saha,Jasim Uddin Khan 한국물리학회 2010 Current Applied Physics Vol.10 No.3

CdO and Al-doped CdO nano-crystalline thin films have been prepared on glass at 300 ℃ substrate temperature by spray pyrolysis. The films are highly crystalline with grain size (18–32 nm) and found to be cubic structure with lattice constant averaged to 0.46877 nm. Al-doping increased the optical transmission of the film substantially. Direct band gap energy of CdO is 2.49 eV which decreased with increasing Al-doping. The refractive index and dielectric constant varies with photon energy and concentration of Al as well. The conductivity of un-doped CdO film shows metallic behavior at lower temperature region. This behavior dies out completely with doping of Al and exhibits semiconducting behavior for whole measured temperature range. Un-doped and Al-doped CdO is an n-type semiconductor having carrier concentration is of the order of ~1021 cm-3, confirmed by Hall voltage and thermo-power measurements.

Effect of Season and Fertilizer on Species Composition and Nutritive Value of Native Grasses

Khan, R.I.,Alam, M.R.,Amin, M.R. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.8

Effect of three major cropping seasons and five fertilizer treatments on botanical composition, nutritional composition and in sacco digestibility of native grasses grown in 30 experimental plots of a medium fertile land was determined. It was observed that all the major grass species were grown in all seasons but their predominancy of growth was different. During the study the predominant grass species were Panicum repens (Angta), Fimvristylis miliacea (Joina), Cyanolis axillaries (Kanainala), Cynodon dactylon (Durba) and Cyperus iria (Phulchaise) which contributed about 27, 20, 13, 11 and 9% of the total grass yield, respectively. Dry matter (DM) contents was higher in dry followed by monsoon and summer seasons (p<0.05). Crude protein (CP) content in the summer and monsoon appeared to be higher (p<0.05) than that of dry season. Organic matter (OM) and neutral detergent fibre (NDF) were higher (p<0.05) in dry and monsoon than in summer season. Application of urea fertilizer and cowdung increased 28.2% of CP content of the grasses, but decreased 19.5 and 9.8% of DM and NDF contents, respectively. The potential degradation of DM and CP of the grasses grown in summer were 4.1 and 8.4% and 3.9 and 5.8% higher than those of monsoon and dry seasons, respectively, and both of these increased (11.3 and 5.9%, respectively) with the application of cowdung and urea fertilizer.