Recycled de-Oiled Algal Biomass Extract as a Feedstock for Boosting Biodiesel Production from <Emphasis Type="Italic">Chlorella minutissima</Emphasis>

The investigation for the first time assesses the efficacy of recycled de-oiled algal biomass extract (DABE) as a cultivation media to boost lipid productivity in Chlorella minutissima and its comparison with Bold’s basal media (BBM) used as control. Presence of organic carbon (3.8 ± 0.8 g/l) in recycled DABE resulted in rapid growth with twofold increase in biomass productivity as compared to BBM. These cells expressed four folds higher lipid productivity (126 ± 5.54 mg/l/d) as compared to BBM. Cells cultivated in recycled DABE showed large sized lipid droplets accumulating 54.12 % of lipid content. Decrement in carbohydrate (17.76 %) and protein content (28.12 %) with loss of photosynthetic pigments compared to BBM grown cells were also recorded. The fatty acid profiles of cells cultivated in recycled DABE revealed the dominance of C16:0 (39.66 %), C18:1 (29.41 %) and C18:0 (15.82 %), respectively. This model is self-sustained and aims at neutralizing excessive feedstock consumption by exploiting recycled de-oiled algal biomass for cultivation of microalgae, making the process cost effective.     

LC-ESI-MS/MS Method for Simultaneous Determination of Triterpenoid Glycosides and Aglycones in Centella asiatica L.

A new and rapid method for simultaneous identification and estimation of bioactive triterpenoid glycosides [asiaticoside (AS) and madecassoside (MS)] and their aglycones [asiatic acid (AA) and madecassic acid (MA)] in Centella asiatica was developed by using high-performance liquid chromatography (HPLC) coupled with triple-quadrupole mass spectrometry (MS/MS). Estimation was based on multiple reaction monitoring (MRM) using the precursor → product ion combination for determination of four analytes using Alltima C18 column (50 × 4.6 mm, 3 µm). An electrospray ionization (ESI) tandem interface in positive mode was employed prior to mass-spectrometric detection. The method was subjected to a thorough validation procedure in terms of linearity, limit of detection (LOD) and quantification (LOQ), accuracy, and precision. Six-point calibration curves were linear in the range of 50–500 ng mL⁻¹ for AS and MS, and 25–250 ng mL⁻¹ for AA and MA, with excellent linearity (R ² > 0.98). With the optimized conditions, the four analytes were detected accurately within 10 min. LOD and LOQ ranged from 2.5 to 5 and 10 to 15 ng mL⁻¹, respectively. Method accuracy in terms of average recoveries of all four analytes ranged between 98.61 and 102.85 % at three spiking levels with intra- and interday precision relative standard deviation (RSD, %) of 1.01–4.62 and 1.13–4.16, respectively. The new method was successfully applied to estimate the concentration of these four bioactive compounds in extracts of C. asiatica prepared by nonpolar-to-polar solvents.

     

Transition from antagonistic to synergistic interaction in mixed micellar system by increase in alkyl chain length of alkyl trimethylammonium bromide

Herein, the electrical conductivity technique used to measure the critical micelle concentration (cmc) for pure cationic surfactants (Dodecyl/cetyltrimethylammonium bromides) and phenothiazine drug (Promethazine hydrochloride), as well as their different mole fractions in 10^?3 ?mol/kg 1-methyl-3-octylimidazolium chloride (C₈mim.Cl) at different temperatures. By using the cmc values the regular solution theory used to evaluate the micellar mole fraction for DTAB/CTAB-PMT mixed systems. The clint's model used to calculate the ideal critical micelle concentration (cmc1) that helps to evaluate the ideal micellar mole fraction for studied mixed systems, both explain the deviation from ideality. In addition, interaction parameter β^m helps to confirm the nature of interaction (either antagonistic or synergistic) for the studied systems. The calculated parameters confirm a transition in the binding nature from antagonistic to synergistic with the increase in alkyl chain length of cationic surfactant i.e., component of the binary mixed system. The ease of micellization for the studied systems discussed by the standard Gibb's energy of micellization ($\Delta G_m^0$), as well as the standard enthalpy and standard entropy of micellization were ($\Delta H_m^0$) and ($\Delta S_m^0$), respectively to discuss the stability of the studied systems.     

Soft matter lithium salt electrolytes: ion conduction and application to rechargeable batteries

Abstract  

Soft matter provides diverse opportunities for the development of electrolytes for all solid state lithium batteries. Here we review soft matter solid electrolytes for lithium batteriesthat are primarily obtained starting from liquid electrolytic systems. This concept of solid electrolyte synthesis from liquid is significantly different from prevalent approaches. The novelty of our approach is discussed in the light of various fundamental issues and in relation to its application to rechargeable lithium batteries.     

Note Synthesis and Characterization of Some New Polyesters from 4, 4′-Dicarboxyacetyldiphenyl Ether and its Dimethyl Ester

In continuation of the work in connection with the synthesis and characterization of polyketoetheresters [1], the present paper describes the synthesis of structurally related polyketoetheresters in which the ether linkage is in the acid moiety of the repeat unit. The polyesters listed in Table 1 were prepared by polycondensation of equimolar amounts of 4,4′-dicarboxyacetyldiphenyl ether (DCADPE) and the required diacetate of dihydroxyarenes and/or of the dimethyl ester of DCADPE and the required aliphatic diol or arene diol in the presence of zinc acetate.     

A New Enrichment Method for Isolation of Bacillus thuringiensis from Diverse Sample Types

New or more efficient methodologies having different principles are needed, as one method could not be suitable for isolation of organisms from samples of diverse types and from various environments. In present investigation, growth kinetics study revealed a higher germination rate, a higher growth rate, and maximum sporulation of Bacillus thuringiensis (Bt) compared to other Bacillus species. Considering these facts, a simple and efficient enrichment method was devised which allowed propagation of spores and vegetative cells of Bt and thereby increased Bt cell population proportionately. The new enrichment method yielded Bt from 44 out of 58 samples. Contrarily, Bt was isolated only from 16 and 18 samples by sodium acetate selection and dry heat pretreatment methods, respectively. Moreover, the percentages of Bt colonies isolated by the enrichment method were higher comparatively. Vegetative whole cell protein profile analysis indicated isolation of diverse population of Bt from various samples. Bt strains isolated by the enrichment method represented novel serovars and possibly new cry2 gene.     

Studies on Polyazomethine Chelate Polymers

Poly-Schiff-base ligand (SBSAL-DDM) is synthesized by condensing bis-salicylaldehyde 5,5′-sulfone with 4,4′-diaminodiphenyl methane. The polychelates of Cu(II), Ni(II), Co(II), and Mn(II) with poly-Schiff base have been isolated and analyzed. The analytical data agree with 1:1 metal-ligand stoichiometry. The polychelates are studied in terms of electrical, thermal, spectral, and magnetic properties. A probable structure has been proposed for the above polymers.     

A New and Convenient Synthesis of 3(2H)-Pyridazinones by Reacting Carbanion of Ethyl Trimethylsilylacetate with Phenylhydrazones

A one-pot synthesis of 5,6-disubstituted-2-phenyl-3(2H)-pyridazinones 4 is achieved on treatment of carbanion of ethyl trimethlsiylacetate with phenylhydrazones of 1,2-dicarbonyl compounds 1.     

Synthesis and structural conformation of N‐substituted 1,4‐dihyropyridine derivatives

N‐(Phenyl)‐3,5‐dicarbethoxy‐2,6‐dimethyl‐4‐(phenyl)‐1,4‐dihydropyridine (A) and N‐(4‐methoxy phenyl)‐‐3,5 dicarbethoxy‐2,6 dimethyl‐4‐(3‐nitro phenyl)‐1,4‐dihydropyridine (B) has been synthesized as per scheme and characterized by the X‐ray diffraction method. The compound A crystallizes in monoclinic space group P21/c with cell parameters a = 9.2770(11)Å, b = 8.6410(5)Å, c = 27.601(3)Å, β = 97.724(3)°, Z = 4. The compound B crystallizes in monoclinic space group P21/c with cell parameters a = 11.229(6), b = 12.746(7)Å, c =17.606(6)Å, β = 104.531(3)°, Z = 4. The structures exhibit both intra and intermolecular hydrogen bonds. Dihydropyridine ring of both the compounds adopt a flat boat conformation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

A new spectrophotometric method for the determination of total and ferric iron in rain water at the ppb level

A new, simple, selective and sensitive spectrophotometric procedure for the on-site quantification of iron at nano-gram levels in atmospheric precipitations, i.e. rain as sample source is described. It is based on the color reaction of Fe³⁺ with SCN^– ions in the presence of a cationic surfactant, i.e. cetylpyridinium chloride (CPC), in strong HCl solution, and subsequent extraction of the complex with N-octylacetamide into toluene or chloroform. The apparent molar absorptivity of the complex is 2.60 × 10⁵ L mol^–1 cm^–1 at λ_max = 480 nm at an enrichment factor (EF) of 10. The detection limit (causing higher absorbance than the sum of the blank absorbance (0.009) and 3 SD) is 5 ng mL^–1 Fe. Ions commonly associated with iron did not interfere in the present method. The effect of analytical variables, i.e. amount and type of the reagents, acidity, solvent, temperature, dilution, etc., in the determination of iron are discussed. The validity of the present method is checked with GF-AAS. The method has been applied to the determination of iron at the ppb level in rain water samples.