Apple Quality as Affected by the Precooling Rate and $O_2$ Pulldown Rate in Controlled Atmosphere Storage

Mahajan, P.V.,Goswami, T.K. Korean Society for Agricultural Machinery 2002 Agricultural and Biosystems Engineering Vol.3 No.1

Quality attributes of apple are greatly affected by the cooling rate and environmental conditions during storage. Studies were conducted to evaluate the effect of cooling rate on different quality attributes of apple. The effect of $O_2$ pulldown rate of the CA chamber on the quality of apple was also determined. Two methods were used viz. conventional CA procedure and rapid CA procedure. Apples stored by medium and slow cooling methods lost its flesh firmness significantly from an initial level of 4.55 kg to 2.83 kg and 2.27 kg, respectively on 35 days after storage whereas, in rapid cooling, the firmness level changed from 4.55 kg to 3.20 kg on 35 days after storage. At the end of 35 days of storage, titratable acidity decreased insignificantly from an initial value of 0.24l% to 0.239% in the case of rapid CA whereas in the case of conventional CA it dropped significantly to 0.215% from its initial level. The initial flesh firmness of 4.55 kg also changed significantly to 4.05 kg on 35 days after storage in conventional CA whereas in rapid CA it changed to 4.36 kg, which was found to be non-significant at 5% level of significance. Total soluble solids increased from an initial level of $12.43^{\circ}$Bx to $12.60^{\circ}C.$ Bx on 35 days after storage in rapid CA whereas it increased to $13.07^{\circ}$ Bx in conventional CA. Ascorbic acid content of apple juice decreased insignificantly from 6.67 mg/100 mL to 5.87 mg/100 mL on 35 days after storage in rapid CA whereas in conventional CA, it decreased significantly to 5.27 mg/100 mL from its initial level.

Facile synthesis of ZnO-Au nanocomposites for high-performance supercapacitors

Mahajan, Hansa,Bae, Joonho,Yun, Kyusik Elsevier 2018 JOURNAL OF ALLOYS AND COMPOUNDS Vol.758 No.-

<P><B>Abstract</B></P> <P>A facile and economic method for the synthesis of ZnO-Au heterostructured nanoflowers was developed by implementing a surfactant-mediated route. Pure ZnO nano-flowers were initially synthesized and Au nanoparticles (NPs) were further deposited on the ZnO surface by using hydrazine hydrate as a reducing agent. The effect of the accumulated Au NPs on the surface of ZnO was demonstrated by applying the as-synthesized nanostructures in supercapacitors. The ZnO-Au composite functioned as a pseudocapacitor electrode in 2 M KOH aqueous electrolyte. The Au NP formed a systematic nanocomposite after deposition on the ZnO surface. The composite exhibited enhanced conductivity and hence high specific capacitance and good cycling stability during cyclic voltammetric and charge/discharge analyses when used as the electrode material in supercapacitors. The average specific capacitance of the fabricated composite was augmented relative increasing from 89 Fg<SUP>-1</SUP> (ZnO nanoflowers) to 205 Fg<SUP>-1</SUP> (ZnO-Au composite) at a scan rate of 20 mVs<SUP>-1</SUP> in a two-electrode system at 0 to 0.8 Ag<SUP>-1</SUP> current density. Metal oxides are considered the most promising materials for next-generation supercapacitors owing to their unique physical and chemical properties. The magnificent performance of the composite material is attributed to the synergetic effects of the size and good redox activity of the ZnO particles, combined with the high surface area of the ZnO-Au composites.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of ZnO nanoflowers and ZnO-Au composite for supercapacitor were proposed. </LI> <LI> The synthesis method is facile, low-cost and low-temperature based. </LI> <LI> Main mechanism of synthesis is investigated. </LI> <LI> ZnO-Au composite demonstrate excellent electrochemical characteristics compared to ZnO nanoflowers. </LI> </UL> </P>

Nano molar level chromogenic and fluorogenic sensing of heavy metal ions using multi-responsive novel Schiff base as a dual mode chemosensor

Mahajan, Prasad G.,Dige, Nilam C.,Vanjare, Balasaheb D.,Kamaraj, Eswaran,Seo, Sung-Yum,Lee, Ki Hwan Elsevier Sequoia 2019 Journal of photochemistry and photobiology Chemist Vol. No.

<P><B>Abstract</B></P> <P>A Schiff base centered chemosensor namely (2<I>E</I>,<I>NE</I>)-<I>N</I>-(2,4-dihydroxybenzylidene)-2-(quinolin-2-ylmethylene)hydrazinecarbothioamide <I>i.e.</I> <B>SB</B> has been synthesized and further utilized for the selective and sensitive detection of four metal ions through dual channels based on absorption and fluorescence properties. The distinctive recognition of Ni<SUP>2+</SUP>, Cu<SUP>2+</SUP>, Co<SUP>2+</SUP>, and Cd<SUP>2+</SUP> in an aqueous solution was achieved by observation with the naked eye rapid color change, analyzing the absorption and fluorescence spectrum of chemosensor <B>SB</B> in the absence and presence of specific metal ion at respective concentration. The synthesized chemosensor <B>SB</B> offered extremely lower detection limit of nano molar level employing either the absorption or fluorescence method. The strong binding constant values such as 9.02 × 10<SUP>5</SUP> M<SUP>−1</SUP> for Ni<SUP>2+</SUP>, 11.21 × 10<SUP>5</SUP> M<SUP>−1</SUP> for Cu<SUP>2+</SUP>, 7.52 × 10<SUP>5</SUP> M<SUP>−1</SUP> for Co<SUP>2+</SUP> and 6.73 × 10<SUP>5</SUP> M<SUP>−1</SUP> for Cd<SUP>2+</SUP> indicate strong complexation between chemosensor <B>SB</B> and respective metal ion. The mechanism for change in the absorption and fluorescence properties of <B>SB</B> involves the interaction of respective metal ion with sulfur and oxygen functionality in <B>SB</B> molecule followed by the formation of ground state non-fluorescent complex <I>via</I> static quenching process. The TD-DFT studies for the theoretical calculations are in support of experimental interpretations. Pleasingly, the present approach allows quantitative determination of said metal ions in water samples at nano molar level.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Schiff base as dual mode chemosensor for detection of Ni<SUP>2+</SUP>, Cu<SUP>2+</SUP>, Co<SUP>2+</SUP> and Cd<SUP>2+</SUP>. </LI> <LI> Rapid naked eye color change and sensitive fluorescence sensing. </LI> <LI> Detection limit at nano molar levels <I>via</I> absorption or fluorescence method. </LI> <LI> TD-DFT based theoretical calculations are in support of experimental findings. </LI> <LI> Effective real water sample analysis for quantitative determination of said metal ions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Occupational asthma and related respiratory diseases

Mahajan, Shailaja G,Mehta, Anita A Kyung Hee Oriental Medicine Research Center 2006 Oriental pharmacy and experimental medicine Vol.6 No.4

Epidemiological evidences and clinical as well as experimental observations have suggested a link between asthma and occupations. This relationship also involves other aspects like nonimmunologic exposures in the environment that can increase the chance of developing work related asthma and respiratory diseases. The purpose of this pamphlet is to supply information of work related diseases, which will give patients suffering with asthma, an intelligent understanding of their disease, and thus stimulate their interest so that they will cooperate more readily with their allergist. Recognizing the symptoms, causes, risk factors, diagnosis and treatment is an important part of managing occupational asthma and related diseases, so that it helps in decline of this rapidly increasing prevalence throughout the world.

IMPROVEMENT AND GENERALIZATION OF A THEOREM OF T. J. RIVLIN

Mahajan Pritika,Khangembam Babina Devi,N. Reingachan,Barchand Chanam 경남대학교 기초과학연구소 2022 Nonlinear Functional Analysis and Applications Vol.27 No.3

In this paper, we generalize as well as sharpen the above inequality. Also our results not only generalize, but also sharpen some known results proved recently.

Selective detection of Co²⁺ by fluorescent nano probe: Diagnostic approach for analysis of environmental samples and biological activities

Mahajan, Prasad G.,Dige, Nilam C.,Desai, Netaji K.,Patil, Shivajirao R.,Kondalkar, Vijay V.,Hong, Seong-Karp,Lee, Ki Hwan Elsevier 2018 Spectrochimica acta. Part A, Molecular and biomole Vol.198 No.-

<P><B>Abstract</B></P> <P>Nowadays scientist over the world are engaging to put forth improved methods to detect metal ion in an aqueous medium based on fluorescence studies. A simple, selective and sensitive method was proposed for detection of Co<SUP>2+</SUP> ion using fluorescent organic nanoparticles. We synthesized a fluorescent small molecule viz. 4,4′-{benzene-1,4-diylbis-[(Z)methylylidenenitrilo]}dibenzoic acid (BMBA) to explore its suitability as sensor for Co<SUP>2+</SUP> ion and biocompatibility in form of nanoparticles. Fluorescence nanoparticles (BMBANPs) prepared by simple reprecipitation method. Aggregation induced enhanced emission of BMBANPs exhibits the narrower particle size of 68nm and sphere shape morphology. The selective fluorescence quenching was observed by addition of Co<SUP>2+</SUP> and does not affected by presence of other coexisting ion solutions. The photo-physical properties, viz. UV-absorption, fluorescence emission, and lifetime measurements are in support of ligand-metal interaction followed by static fluorescence quenching phenomenon in emission of BMBANPs. Finally, we develop a simple analytical method for selective and sensitive determination of Co<SUP>2+</SUP> ion in environmental samples. The cell culture <I>E</I>. <I>coli</I>, <I>Bacillus</I> sps., and <I>M</I>. <I>tuberculosis H</I> <SUB> <I>37</I> </SUB> <I>RV</I> strain in the vicinity of BMBANPs indicates virtuous anti-bacterial and anti-tuberculosis activity which is of additional novel application shown by prepared nanoparticles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New fluorescent Nano probe developed for detection of Co<SUP>2+</SUP> in aqueous medium </LI> <LI> Selective fluorescence quenching induced by Co<SUP>2+</SUP> only </LI> <LI> Quenching mechanism disclose ground state complexation and ligand (COO<SUP>–</SUP>) – metal (Co<SUP>2+</SUP>) interaction </LI> <LI> Lower detection limit for Co<SUP>2+</SUP> = 0.102 µg/mL </LI> <LI> The practical application includes analysis of environmental samples and biological activities </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>

Facile synthesis of new quinazolinone benzamides as potent tyrosinase inhibitors: Comparative spectroscopic and molecular docking studies

Mahajan, Prasad G.,Dige, Nilam C.,Vanjare, Balasaheb D.,Raza, Hussain,Hassan, Mubashir,Seo, Sung-Yum,Kim, Chong- Hyeak,Lee, Ki Hwan Elsevier Scientific Pub. Co 2019 Journal of molecular structure Vol.1198 No.-

<P><B>Abstract</B></P> <P>The simple reaction approach has been designed and utilized for the synthesis of quinazolinone benzamides <B>4a-4h</B> using isatoic anhydride, <I>m-</I>Anisic hydrazide and various aldehydes. The formation of target compounds was confirmed by spectral characterization techniques such as IR, NMR, Mass and elemental analysis. The spectrophotometric investigations based on absorption and fluorescence outputs denote distinctive properties such as molar extinction coefficient, fluorescence emission, fluorescence lifetime, quantum yield and Stokes shift for compounds <B>4a-4h</B> in three different solvents. Along with spectroscopic studies, synthesized compounds <B>4a-4h</B> were tested for bioevaluation against tyrosinase inhibitory activity. Pleasingly, all compounds displayed lower IC<SUB>50</SUB> values (0.006 ± 0.074 to 1.609 ± 0.324 μM) than standard kojic acid (16.832 ± 1.162 μM) against tyrosinase inhibition. The comparative spectrophotometric properties, <I>in vitro</I> and <I>in silico</I> analysis suggest that compounds <B>4d</B> and <B>4f</B> have significant absorption and fluorescence properties in addition to extremely low IC<SUB>50</SUB> values as potent tyrosinase inhibitors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ease of synthesis for quinazolinone benzamides <B>4a-4h</B>. </LI> <LI> Insights to comparative spectroscopic properties in different solvents. </LI> <LI> <I>In vitro</I> bio-evaluation against tyrosinase enzyme. </LI> <LI> <I>In silico</I> molecular docking studies are in supports of <I>In vitro</I> findings. </LI> <LI> Synthesized compounds can be beneficial as template in molecular drug design. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Synthesis and Studies of Fluorescein Based Derivatives for their Optical Properties, Urease Inhibition and Molecular Docking

Mahajan, Prasad G.,Dige, Nilam C.,Vanjare, Balasaheb D.,Raza, Hussain,Hassan, Mubashir,Seo, Sung-Yum,Hong, Seong-Karp,Lee, Ki Hwan Springer-Verlag 2018 JOURNAL OF FLUORESCENCE Vol.28 No.6

Synthesis, Photophysical Properties and Application of New Porphyrin Derivatives for Use in Photodynamic Therapy and Cell Imaging

Mahajan, Prasad G.,Dige, Nilam C.,Vanjare, Balasaheb D.,Phull, Abdul Rehman,Kim, Song Ja,Hong, Seong-Karp,Lee, Ki Hwan Springer-Verlag 2018 JOURNAL OF FLUORESCENCE Vol.28 No.4

A potential mediator for photodynamic therapy based on silver nanoparticles functionalized with porphyrin

Mahajan, Prasad G.,Dige, Nilam C.,Vanjare, Balasaheb D.,Eo, Seong-Hui,Seo, Sung-Yum,Kim, Song Ja,Hong, Seong-Karp,Choi, Chang-Shik,Lee, Ki Hwan Elsevier 2019 Journal of photochemistry and photobiology Chemist Vol.377 No.-

<P><B>Abstract</B></P> <P>The development of photodynamic therapy (PDT) agent’s emphasis on metal nanoparticles loaded with porphyrin derivative has been explored in the present investigation. For this purpose, a novel porphyrin derivative 5,10,15,20-Tetrakis(2,4-dihydroxyphenyl) porphyrin (POR) was synthesized and characterized at a molecular scale. The synthesized POR was loaded on the surface of simply prepared mercaptosuccinic acid (MSA) capped silver nanoparticles(MSA-AgNPs). The formation of newly designed nanocomposite system (POR-MSA-AgNPs) was confirmed by different characterization techniques such as Zeta-Particle size analyzer, X-ray photoelectron spectroscopy (XPS) and Field emission scanning electron microscopy (FE-SEM). While optical properties were investigated by UV–Vis. absorption spectroscopy and fluorescence spectroscopy. In order to explore the capacity of synthesized nanosystem as a competent photosensitizer in PDT, the efficiency of singlet oxygen generation was successfully estimated using photooxidation of 9,10-Dimethylanthracene. An efficiency of singlet oxygen quantum yield was seen higher when the POR is incorporated onto MSA-AgNPs rather than in its free form. In an addition, synthesized nanocomposite could be a potent candidate for cell imaging application against cancer cell line A375 with non-toxic behavior. Thus, the excellent photophysical properties, significant singlet oxygen generation efficiency and cell imaging application of POR-MSA-AgNPs can open a new window to explore it as PDT agent in bioanalytical, drug formulation and biosensing field.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of novel porphyrin derivative <B>POR</B>. </LI> <LI> Ease of preparation for Mercaptosuccinic acid capped silver nanoparticles. </LI> <LI> Efficacy of singlet oxygen quantum yield for <B>POR-MSA-AgNPs</B>. </LI> <LI> Non-toxic nature signifies utility of <B>POR-MSA-AgNPs</B> in cell imaging. </LI> <LI> <B>POR-MSA-AgNPs</B> could be potent candidate in PDT and biosensing field. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>