Bioactivity-guided isolation of Laccaic Acid-A: A potent anti-cancer agent from Laccifer lacca (Kerr)

677-685Laccifer lacca (Kerr) (LL) has widely been used as pigmenting, dying and coloring agent in chemical industry. Although, it has wide range of industrial applications, but unfortunately, due to lesser availability of data, it has been ignored. Keeping in mind, the broad application of Laccifer lacca (Kerr), we tried to report the in vitro anti-cancer effects along with its chemical characterization. This work is divided into two sections, first section to assess the anti-cancer activity of dye of Laccifer lacca (Kerr) employing SRB assay. In second section, the active fraction was processed to isolate the active chemical entities using preparative gradient HPLC-UV. The detector was set at 275 nm and 360 nm as reference wavelength. Results of ethyl acetate fraction (EA) showed promising anti-cancer spectrum for MDA-MB-231 (Laccifer lacca. In conclusion, our results suggested being the first report for isolation of laccaic acid-A from Laccifer lacca. We characterized the isolated compound be UV, IR, NMR and Mass spectrometry. We also propose that this is the first report for isolation of laccaic acid-A using preparative HPLC with a good yield and purity

Mechanism and theory of d-glucopyranose homogeneous acid catalysis in the aqueous solution phase

peer-reviewedA detailed systematic theoretical study of the mechanism of the homogeneous Brønsted -acid catalysis of D-glucose in aqueous solution phase ("acid hydrolysis") is reported. G4MP2 with the SMD solvation model at B3LYP/6-31G(2df,p) are employed to compute the free energies of the molecular and ionic species pertaining to the isomerization, protonation, hydrogen cation transfer and decomposition processes of D-glucopyranose in aqueous solution phase. This information is used to hypothesise a reaction mechanism that is of improved accuracy and completeness from the existing art. It is found that rotation of the D-glucose alkyl carbon-carbon bond is a facile process and is very important to the subsequent catalytic mechanism. This rotation produces two rotameric isomers which are of notably different thermodynamic stability and reactivity, even with regard to the products of this acid catalysis. As a low energy process =E2 = ~3.8 6.7 kcal/mol), the alkyl carbon-carbon bond may rotate toward the hydroxyl group at the adjacent "4" position reducing the energy required to protonate that position by 3.0 7.2 kcal/mol (or 15 30 %). The combination of two rotomeric isomers with the six structural isomers owing to the oxygen atoms, means that protonated D-glucose cations embark on a complex competition of interconversion and decomposition that is both thermodynamically and kinetically influenced. The calculations support the hypothesis that the acid-catalysed hydrolysis of D-glucose may yield a number of platform chemicals that have not previously been suggested. These include the prospect of three isomers of 5-hydroxymethylfurfural (HMF); 5- (hydroxymethyl)furan-2-carbaldehyde, 5-(hydroxymethyl)furan-3-carbaldehyde and 5-(hydroxymethyl)furan-4- carbaldehyde. Vibrational spectra of these HMF isomers are also computed and compared to experimentally determined infrared spectra of "humins". On this basis, it is cautiously speculated that the alternative HMF isomers, may be monomeric constituent of the polymeric "humins"

Degree of Complementarity Determines the Nonlocality in Quantum Mechanics

Complementarity principle is one of the central concepts in quantum mechanics which restricts joint measurement for certain observables. Of course, later development shows that joint measurement could be possible for such observables with the introduction of a certain degree of unsharpness or fuzziness in the measurement. In this paper, we show that the optimal degree of unsharpness, which guarantees the joint measurement of all possible pairs of dichotomic observables, determines the degree of nonlocality in quantum mechanics as well as in more general no-signaling theories.Comment: Close to published versio

A comparative study of neonatal and maternal outcome between forceps delivery and vacuum extraction

Background: Aims and objectives of the study were to compare maternal and neonatal outcomes of forceps versus vacuum application in assisted vaginal delivery. Methods: This prospective study was conducted in a tertiary care hospital of West Bengal over one year. Women in labor with vertex presentation were delivered by vacuum and forceps. A total of 100 cases were included of which 50 patients selected for forceps delivery and 50 patients for vacuum extraction. The instruments were either silastic cup vacuum extractor or Wrigley`s outlet forceps. Maternal morbidity was studied in terms of cervical tears, vaginal lacerations, episiotomy extension, perineal tears, PPH, and retention of urine. Neonatal morbidity was studied in terms of Apgar score, instrumental injuries, cephalhematoma, NICU admission and the outcome was compared. Chi square test was used to analyze the data. Results: Observations maternal morbidity viz. episiotomy extension, traumatic PPH were significant in the forceps group (p=0.01). With regards to neonatal morbidity, SNCU admission were significantly higher in forceps delivery (p=0.02) and incidence of cephalohematomas were more in ventouse delivery (p=0.02). Conclusions: Vacuum and forceps should remain appropriate tools in the armamentarium of the modern obstetrician. However, ventouse may be chosen first (if there is no fetal distress) as it is significantly less likely to injure the mother.