Anti-bacterial activity, anti-cancer activity and nanofiber formation of certain poly (ester amides) from 2,5-pyridine dicarboxylic acid

A new series of four poly(ester amides) were synthesized by direct polycondensation of 2,5-pyridine dicarboxylic acid  with two different varying diols and diamines in pyridine medium using diphenylchlorophosphate as a condensation agent. The two diamines employed in the synthesis were 4,4’-diamino diphenyl methane and 1,4-diamino benzene. The arylidenediols 2,5-bis(4-hydroxy-3-methoxybenzylidene)cyclopentanone and 2,6-bis(4-hydroxy-3-methoxybenzylidene) cyclohexanone were also used. The synthesized poly(ester amides) were characterized by qualitative solubility test, FT-IR, 1H and 13C-NMR spectra. The monomeric moieties were found by spectroscopic analysis to be well incorporated in the polymer back bone. The thermal phase transition behavior of the poly(ester amides) were investigated by differential thermo gravimetry (DTG). The nanofibers of synthesized poly(ester amides) with PVC and composite fibers with PVC/nanoclay were formed by electrospinning.  The morphology of these composite fibers was studied by scanning electron microscopy (SEM). These poly(ester amides) were screened for their anti-bacterial potential in vitro against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Bacillus subtilis. In vitro anti-cancer activities of synthesized polymers were also evaluated against MCF7 human breast carcinoma cells. The results show that the polymers exhibited significant anti-bacterial and anti-cancer activity. Keywords: Poly (ester amides), Anti-bacterial activity, Nano fiber, Anticancer activit

2-Hy­droxy­ethyl 4-hy­droxy­benzoate

In the title compound, C9H10O4, the dihedral angle between the benzene ring and the –CO2 unit is 11.93 (8)° and the conformation of the 2-hy­droxy­ethyl side chain is gauche [O—C—C—O = −71.91 (17)°]. In the crystal, mol­ecules are linked by O—H⋯O and C—H⋯O hydrogen bonds

Anthropogenic influence on the drivers of the Western Cape drought 2015-2017

In the period 2015-2017, the Western Cape region has suffered from three consecutive years of below average rainfall - leading to a prolonged drought and acute water shortages, most prominently in the city of Cape Town. After testing that the precipitation deficit is the primary driver behind the reduced surface water availability, we undertake a multi-method attribution analysis for the meteorological drought, defined in terms of a deficit in the 3 years running mean precipitation averaged over the Western Cape area. The exact estimate of the return time of the event is sensitive to the number of stations whose data is incorporated in the analysis but the rarity of the event is unquestionable, with a return time of more than a hundred years. Synthesising the results from five different large model ensembles as well as observed data gives a significant increase by a factor of three (95% confidence interval 1.5-6) of such a drought to occur because of anthropogenic climate change. All the model results further suggest that this trend will continue with future global warming. These results are in line with physical understanding of the effect of climate change at these latitudes and highlights that measures to improve Cape Town's resilience to future droughts are an adaptation priority

Differential Expression of Iron Acquisition Genes by Brucella melitensis and Brucella canis during Macrophage Infection

Brucella spp. cause chronic zoonotic disease often affecting individuals and animals in impoverished economic or public health conditions; however, these bacteria do not have obvious virulence factors. Restriction of iron availability to pathogens is an effective strategy of host defense. For brucellae, virulence depends on the ability to survive and replicate within the host cell where iron is an essential nutrient for the growth and survival of both mammalian and bacterial cells. Iron is a particularly scarce nutrient for bacteria with an intracellular lifestyle. Brucella melitensis and Brucella canis share ∼99% of their genomes but differ in intracellular lifestyles. To identify differences, gene transcription of these two pathogens was examined during infection of murine macrophages and compared to broth grown bacteria. Transcriptome analysis of B. melitensis and B. canis revealed differences of genes involved in iron transport. Gene transcription of the TonB, enterobactin, and ferric anguibactin transport systems was increased in B. canis but not B. melitensis during infection of macrophages. The data suggest differences in iron requirements that may contribute to differences observed in the lifestyles of these closely related pathogens. The initial importance of iron for B. canis but not for B. melitensis helps elucidate differing intracellular survival strategies for two closely related bacteria and provides insight for controlling these pathogens

Synthesis of Certain Poly[bis(benzylidene)] Esters and Investigation on their Photocrosslinkability

Random copolyesters were synthesized directly from respective diacids and diols with diphenylchlorophosphate (DPCP) as a polycondensation agent. These polymers were characterized by FT-IR and NMR spectrometry. Interestingly, they were observed to possess photocrosslinkability which was established using scanning electron microscopy by UV irradiation experiments. Photocrosslinkable polymers have significant applications in the field of non-linear optics, in the generation of photoresists and photorefractive materials

BIOCHEMICAL AND PIGMENT ANALYSIS ON PHYCOREMEDIATED MICROALGAL BIOMASS

<p>Phycoremediation is a term of treating microalgae with waste water to reduce the<br>toxic elements in it. Textile dye industrial effluents contain highly concentrated CO2 and<br>Nitrogen in it, which causes severe harmful effects to human and to the environment. The<br>reduction of Physiochemical parameters were seen from before and after treated effluents.<br>Biochemical analysis from the microalgae biomass reveals that Scenedesmus obliquus, Chlorella<br>vulgaris and its consortium have shown high amount of Protein and Lipid in ascending order.<br>Microalgae pigments such as chlorophyll a, b and â-carotene were determined and â-carotene<br>found high amount than chlorophyll from all the treated biomass as expected but high than<br>normal grown media. Scenedesmus obliquus is found to be the highest producer of â-carotene.<br>Positive and negative correlation were analysed between removal of nitrogen from the effluent<br>and increase in protein content and removal of COD from the effluent and high lipid content<br>(Positive) and Increase in Lipid content leads to decrease in â-carotene levels (Negative).</p> <p> </p