Antimicrobial properties of black grape (Vitis vinifera L.) peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds

Aim:

Black grape peel possesses a substantial amount of polyphenolic antimicrobial compounds that can be used for controlling the growth of pathogenic microorganisms. The purpose of this study was to assess antibacterial and antifungal activity of black grape peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds, respectively.

Materials and Methods:

Peel of grape was subjected to polyphenolic extraction using different solvents viz., water, ethanol, acetone, and methanol. Antibiotic-resistant strains of Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Salmonella typhimurium, and Escherichia coli were screened for the antibacterial activity of different grape extracts. Antibacterial activity was analyzed using agar well diffusion method. Penicillium chrysogenum, Penicillium expansum, Aspergillus niger and Aspergillus versicolor were screened for the antifungal activity. Antifungal activity was determined by counting nongerminated spores in the presence of peel extracts.

Results:

As compared to other solvent extracts, methanol extracts possessed high antibacterial and antifungal activity. S. typhimurium and E. coli showed complete resistance against antibacterial action at screened concentrations of grape peel extracts. Maximum zone of inhibition was found in case of S. aureus, i.e., 22 mm followed by E. faecalis and E. aerogenes, i.e., 18 and 21 mm, respectively, at 1080 mg tannic acid equivalent (TAE)/ml. The maximum and minimum percent of growth inhibition was shown by P. expansum and A. niger as 73% and 15% at 1080 TAE/ml concentration of grape peel extract, respectively.

Conclusions:

Except S. typhimurium and E. coli, growth of all bacterial and mold species were found to be significantly (P < 0.05) inhibited by all the solvent extracts.KEY WORDS: Antibacterial activity, antifungal activity, polyphenolic compounds, Vitis vinifera L, zone of inhibition     

Ag2O nanoparticle-catalyzed substrate-controlled regioselectivities: direct access to 3-ylidenephthalides and isocoumarins

Herein, we disclose the first example of an efficient, silver oxide nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides 11–16 and isocoumarins 17–20via sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively. This one pot coupling involves reaction of substituted 2-halobenzoic acid with meta/para-substituted and ortho-substituted terminal alkynes, which proceeded in a regioselective manner resulting in the formation of 3-ylidenephthalides or isocoumarins, respectively, in excellent yields (up to 95%) with complete Z-selectivity. This protocol features relatively broad substrate scope, mild conditions, operational simplicity, and is favourable with aromatic/alicyclic terminal alkynes. The competition experiments and gram-scale synthesis further highlight the importance and versatility of the methodology. The proposed mechanistic pathways illustrate that the regioselectivity is substantially being controlled by the substituent(s) present on the acetylenic phenyl ring.

We report the first example of an efficient, Ag₂O nanoparticle-catalyzed, direct regioselective synthesis of 3-ylidenephthalides and isocoumarins via Sonogashira type coupling followed by substrate-controlled 5-exo-dig or 6-endo-dig cyclization reaction, respectively.     

Mycophenolate in idiopathic inflammatory myositis: outcome data of a large South Asian cohort

Clinical Rheumatology - Consensus on treatment of idiopathic inflammatory myositis (IIM), particularly with regard to flares and interstitial lung disease (ILD), does not exist. We studied the...     

Association of Interleukin-1β-31C/T, -511T/C and -3954C/T Single Nucleotide Polymorphism and Their Blood Plasma Level in Acquired Aplastic Anemia

Aplastic anemia (AA) is an immune-mediated disorder in which hematopoietic stem and progenitor cells are targeted by a number of cellular and molecular pathways. This case control study aims to investigate the association of interleukin-1beta (IL-1β) gene polymorphisms, (IL-1β-31, IL-1β-511 and IL-1β-3954) and their plasma levels with acquired AA. Genotyping was done by Restricted Fragment Length Polymorphism (PCR–RFLP) method and IL-1β plasma levels were evaluated in peripheral blood using ELISA. Increased level of IL-1β was reported to be significant in cases as compared to controls. The susceptibility of developing AA was higher in the cases for IL-1β-3954 genotype. IL-1β-511 genotype showed significant association with the severity groups of AA. No significant association was noticed in responder versus non-responder group. Plasma level of IL-1β gene was found to be significantly higher in severe and very-severe group of AA versus control group. Our findings suggest that IL-1β gene and its genotypes might be involved in the pathophysiology of AA and play a central role in the etiopathogenesis of AA.     

An audit of percutaneous drainage for acute necrotic collections and walled off necrosis in patients with acute pancreatitis

Background and objectives

Percutaneous catheter drainage (PCD) is used as a first step in the management of symptomatic fluid collections in patients with acute pancreatitis (AP). We aimed to compare the outcome of patients with acute necrotic collection (ANC) and those with walled-off necrosis (WON), who had undergone PCD as a part of management of AP.

Research on tuberculosis in tribal areas in India: A systematic review

Background

Tuberculosis (TB) remains a major public health problem in resource-poor countries including India. Scientific knowledge is used to guide policy and practice. There is however, a limited, systematically collected data required for guiding the scale-up of interventions particularly amongst vulnerable populations including tribal groups in the country. In view of this, a systematic review of the TB research studies carried out in tribal areas of different parts of the country was undertaken.

Micro-array Analysis of Cold Tolerant Tomato Expressing Nicotiana tabacum Osmotin

Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Our earlier studies have established improved cold tolerance in the transgenic tomato (Solanum lycopersicum...     

Immunomodulatory Effects of Curcumin

Curcumin (diferuloylmethane), found in the spice turmeric, exhibits anti-inflammatory, antioxidant, and chemopreventive activities. However, the effect of curcumin on the immunological responses largely remains unknown. In this study we have investigated the effect of curcumin on mitogen (phytohaemagglutinin; PHA) stimulated T-cell proliferation, natural killer (NK) cell cytotoxicity, production of cytokines by human peripheral blood mononuclear cells (PBMCs), nitric oxide (NO) production in mouse macrophage cells, RAW-264.7. Furthermore, we have carried out an electromobility shift assay to elucidate the mechanism of action of curcumin at DNA protein interaction level. We observed that curcumin inhibits PHA-induced T-cell proliferation, interleukin-2 production, NO generation, and lipopolysachharide-induced nuclear factor-κB (NF-κB) and augments NK cell cytotoxicity. Our results suggest that curcumin most likely inhibits cell proliferation and cytokine production by inhibiting NF-κB target genes involved in the induction of these immune parameters.     

Characterization of a new begomovirus and a beta satellite associated with the leaf curl disease of French bean in northern India

Begomoviruses are emerging as serious threat to many crops throughout the world particularly in tropical and sub-tropical regions. A leaf curl disease with symptoms typical of infection by many begomoviruses was observed in French bean (Phaseolus vulgaris) at Kanpur, India, during 2010–2012. The disease caused downward leaf curling and made the plants unproductive. The disease was transmitted from infected to healthy plants through whitefly (Bemisia tabaci). The products of five samples digested with EcoRI yielded DNA fragments of about 2.7 kb. The complete sequence of the Fb1 sample comprised 2,741 nucleotides with genome organization typical of begomoviruses having two ORFs in virion-sense and five ORFs in complementary-sense separated by an intergenic region with begomovirus conserved nonanucleotide sequence, TAATATTAC. The complete DNA-A sequence homology was most closely related to Cotton leaf curl Bangalore virus with 80 % nucleotide sequence identity. Based on the demarcation criteria for identifying a begomovirus species, Fb1 is considered as a distinct begomovirus species, named French bean leaf curl virus and designated as FbLCV-[IN:Knp:12]. The complete sequence of associated satellite DNA-β comprises 1,379 nucleotides with single ORF and has 80 % identity with Papaya leaf curl beta satellite. There was no evidence of recombination in DNA-A of FbLCV and associated beta satellite DNA molecule.