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>

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.

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.

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.

A Class of Multivalent Functions with Negative Coefficients Defined by Convolution

R. M. Ali,M. H. Khan,V. Ravichandran,K. G. Subramanian 대한수학회 2006 대한수학회보 Vol.43 No.1

For a given $p$-valent analytic function $g$ with positive coefficients in the open unit disk $\UD$, we study a class of functions $f(z)=z^p-\sum_{n=m}^\infty a_nz^n$\ ($a_n\geq 0$) satisfying \[ \frac{1}{p}\Re \left( \frac{z(f*g)'(z)}{(f*g)(z)}\right) > \alpha\quad (0\leq \alpha<1; z\in\Delta).\] Coefficient inequalities, distortion and covering theorems, as well as closure theorems are determined. The results obtained extend several known results as special cases.

Rheological and mechanical properties of ABS/PC blends

Khan M.M.K.,Liang R.F.,Gupta R.K.,Agarwal S. The Korean Society of Rheology 2005 Korea-Australia rheology journal Vol.17 No.1

Acrylonitrile-Butadiene-Styrene (ABS), polycarbonate (PC) and their alloys are an important class of engineering thermoplastics that are widely used for automotive industry, computer and equipment housings. For the process of recycling mixtures of ABS and PC, it is desirable to know how sensitive the blend properties are to changes in compositions. It was for this reason that blends of virgin ABS and virgin PC at five different compositions, namely, $15\%,\;30\%,\;50\%,\;70%$ and $85\%$ by weight of ABS were prepared and characterised by rheological and mechanical measurements. Rheological properties of these blends in steady, oscillatory and transient step shear and mechanical properties, namely, tensile strength, elongation-at-break and Izod impact strength are reported. The results show that PC behaves in a relatively Newtonian manner, but ABS exhibits significant shear thinning. The ABS-rich blends show a trend that is similar to that of ABS, while PC-rich blends, namely $0\%$ and $15\%$, exhibit a nearly Newtonian behaviour. However, at a fixed shear rate or frequency, the steady shear or the dynamic viscosity varied respectively in a non-mono-tonic manner with composition. Except for $15\%$ blend, the viscosities of other blends fall into a narrow band indicating a wide-operation window of varying blend ratio. The blends exhibited a lower viscosity than either of the two pure components. The other noticeable feature was that the blends at $70\%$ and $85\%$ ABS content had a higher G' than pure ABS, indicating an enhancement of elastic effect. The tensile yield strength of the blends followed the 'rule of mixtures' showing a decreasing value with the increase of ABS content in PC. However, the elongation-at-break and the impact strength did not appear to obey this 'rule of mixtures,' which suggests that morphology of the blends also plays a significant role in determining the properties. Indeed, scanning electron micrographs of the fracture surfaces of the different blends validate this hypothesis, and the $15\%$ blend is seen to have the most distinct morphology and correspondingly different behaviour and properties.

Host plant growth promotion and cadmium detoxification in Solanum nigrum, mediated by endophytic fungi

Khan, A.R.,Ullah, I.,Waqas, M.,Park, G.S.,Khan, A.L.,Hong, S.J.,Ullah, R.,Jung, B.K.,Park, C.E.,Ur-Rehman, S.,Lee, I.J.,Shin, J.H. Academic Press 2017 Ecotoxicology and environmental safety Vol.136 No.-

<P>Current investigation conducted to evaluate the associated fungal endophyte interactions of a Cd hyper accumulator Solanum nigrum Korean ecotype under varying concentrations of Cd. Two indole-3-acetic acid (IAA) producing fungal strains, RSF-4L and RSF-6L, isolated from the leaves of S. nigrum, were initially screened for Cd tolerance and accumulation potential. In terms of dry biomass production, the strain RSF-6L showed higher tolerance and accumulation capacity for Cd toxicity in comparison to RSF-4L. Therefore, RSF-6L was applied in vivo to S. nigrum and grown for six weeks under Cd concentrations of 0, 10, and 30 mg Kg(-1) of dry sand. The effect of fungal inoculation assessed by plant physiological responses, endogenous biochemical regulations, and Cd profile in different tissues. Significant increase were observed in plant growth attributes such as shoot length, root length, dry biomass, leaf area, and chlorophyll contents in inoculated RSF-6L plants in comparison to non-inoculated plants with or without Cd contamination. RSF-6L inoculation decreased uptake of Cd in roots and above ground parts, as evidenced by a low bio-concentration factor (BCF) and improved tolerance index (TI). However, Cd concentration in the leaves remained the same for inoculated and non-inoculated plants under Cd spiking. Fungal inoculation protected the host plants, as evidenced by low peroxidase (POD) and polyphenol peroxidase (PPO) activities and high catalase (CAT) activity. Application of appropriate fungal inoculation that can improve tolerance mechanisms of hyper-accumulators and reduce Cd uptake can be recommended for phyto-stabilisation/immobilisation of heavy metals in crop fields. (C) 2016 Elsevier Inc. All rights reserved.</P>

Rheological and mechanical properties of ABS/PC blends

M.M.K. Khan,R.F. Liang,R.K. Gupta,S. Agarwal 한국유변학회 2005 Korea-Australia rheology journal Vol.17 No.1

Acrylonitrile-Butadiene-Styrene (ABS), Polycarbonate (PC) and their alloys are an important class of engineering thermoplastics that are widely used for automotive industry, computer and equipment housings. For the process of recycling mixtures of ABS and PC, it is desirable to know how sensitive the blend properties are to changes in compositions. It was for this reason that blends of virgin ABS and virgin PC at five different compositions, namely, 15%, 30%, 50%, 70% and 85% by weight of ABS were prepared and characterised by rheological and mechanical measurements. Rheological properties of these blends in steady, oscillatory and transient step shear and mechanical properties, namely, tensile strength, elongation-at-break and Izod impact strength are reported. The results show that PC behaves in a relatively Newtonian manner, but ABS exhibits significant shear thinning. The ABS-rich blends show a trend that is similar to that of ABS, while PC-rich blends, namely 0% and 15%, exhibit a nearly Newtonian behaviour. However, at a fixed shear rate or frequency, the steady shear or the dynamic viscosity varied respectively in a non-monotonic manner with composition. Except for 15% blend, the viscosities of other blends fall into a narrow band indicating a wide-operation window of varying blend ratio. The blends exhibited a lower viscosity than either of the two pure components. The other noticeable feature was that the blends at 70% and 85% ABS content had a higher G’ than pure ABS, indicating an enhancement of elastic effect. The tensile yield strength of the blends followed the ‘rule of mixtures’ showing a decreasing value with the increase of ABS content in PC. However, the elongation-at-break and the impact strength did not appear to obey this ‘rule of mixtures,’ which suggests that morphology of the blends also plays a significant role in determining the properties. Indeed, scanning electron micrographs of the fracture surfaces of the different blends validate this hypothesis, and the 15% blend is seen to have the most distinct morphology and correspondingly different behaviour and properties.

Supplementation of lycopene in maturation media improves bovine embryo quality in vitro

Chowdhury, M.M.R.,Choi, B.H.,Khan, I.,Lee, K.L.,Mesalam, A.,Song, S.H.,Xu, L.,Joo, M.D.,Afrin, F.,Kong, I.K. Butterworths, etc ; Elsevier Science Ltd 2017 Theriogenology Vol.103 No.-

This study sought to modulate factors that reduce embryo quality in in vitro culture (IVC) systems. Over eight replicates, 3075 oocytes were cultured in in vitro maturation media containing various concentrations of lycopene, followed by in vitro fertilization and culture. The percentages of MII-stage oocytes, the presumptive zygotes that underwent cleavage and developed into blastocysts were significantly (P < 0.05) higher, the intracellular ROS concentrations reduced significantly (P < 0.05) in oocytes/blastocysts, TUNEL assay demonstrates reduced apoptosis and increased total cell number per blastocyst (P < 0.05), Immunocytochemistry confirmed that diminished protein expression of nuclear factor kappa B (NFκB), cyclooxygenase-2 (COX2), and 8-oxoguanine (indicated by ROS) and relative mRNA expression of the Caspase-3, NFκB, COX2, iNOS and BCL2-associated X (BAX) was significantly (P < 0.05) lower whereas the anti-apoptotic gene BCL2 was significantly (P < 0.05) higher in the 0.2 μM lycopene-supplemented group than the control. In conclusion, lycopene improves blastocyst quality by overcoming unfavorable conditions in in vitro culture systems.

Nutritional Evaluation of Distillery Sludge and Its Effect as a Substitute of Canola Meal on Performance of Broiler Chickens

Sharif, M.,Shahzad, M.A.,Rehman, S.,Khan, S.,Ali, R.,Khan, M.L.,Khan, K. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.3

The study was conducted to investigate the chemical composition of distillery yeast sludge and its inclusion in broiler diets to replace canola meal. Raw distillery yeast sludge was washed with water using water and sludge in the ratio 6:1, respectively. Proximate analysis of raw distillery yeast sludge and washed distillery sludge was carried out for crude protein (CP), true protein (TP), ether extract (EE), ash, acid insoluble ash and nitrogen free extract (NFE) determination. Mineral contents and amino acid profile of raw distillery yeast sludge and washed distillery sludge were also determined. After chemical evaluation, four iso-caloric and iso-nitrogenous broiler starter and finisher diets were prepared in mash form using 0 (control), 4, 8 and 12% levels of washed distillery sludge replacing canola meal. One hundred and twenty day-old broiler chicks were randomly distributed into 12 experimental units in such a way that each diet was offered to three experimental units, each comprising of 10 chicks. It was observed that washing affected the nutrients either by decreasing or increasing their concentration. It decreased the total mineral contents whereas CP, TP, EE and NFE contents increased. Washing also increased amino acid profile. Average feed intake and weight gain were higher in birds fed diet containing 8% washed distillery sludge and lower in birds fed diet containing 0% washed distillery sludge. Feed cost per kg live weight gain decreased significantly as the level of washed distillery sludge was increased in the diet. Average heart, liver and pancreas weights decreased with increased level of washed distillery sludge in the diet. The study revealed that after washing, distillery yeast sludge can be used successfully in broiler diets up to the level of 8% without any adverse effect on broiler's performance.