scholarly journals PARTIAL CHARACTERIZATION AND ANTIMICROBIAL PROPERTY OF SMALL PEPTIDES ISOLATED FROM THE FLOWERS OF MILLINGTONIA HORTENSIS

Author(s):  
Angayarkanni R ◽  
Sridevi G

Objective: The flowers of Millingtonia hortensis were initially screened for the presence of Cu (II) ninhydrin-positive compounds. Purification and characterization of small alpha peptides from the flowers of M. hortensis have been done. Further elucidation of the antimicrobial properties of these small peptides is also taken as part of the work.Methods: Using 80% aqueous ethanol the crude extract was prepared and screening was carried out by a circular paper chromatographic technique. Purification and characterization of small alpha peptides from the flowers of M. hortensis have been done. Further elucidation of the antimicrobial properties of these small peptides by disc diffusion method is also taken as part of the work.Results: Based on the findings of UV–visible spectrophotometer, it is confirmed that the purified compound is a small peptide and might contain glycine, cysteine, and tyrosine or histidine. The result of antimicrobial studies proves the ability of small peptides to function as antimicrobial peptides.Conclusion: It is concluded that the small peptides show an inhibitory effect against various Gram-negative and some Gram-positive bacteria.

2019 ◽  
pp. 27-32
Author(s):  
Emőke Mihok ◽  
Éva György ◽  
Endre Máthé

Wild berry is an excellent source of phytonutrients and/or bioactive compounds associated with significant therapeutic properties, so that they have been utilized in folk medicine and traditional nutrition throughout centuries. Multiple health-promoting effects, such as anti-inflammatory, anti-diabetic, anti-heart and coronary disease properties were attributed to such wild berries. It has also been proved that berries could feature antimicrobial effects that could be of a great importance for the prevention of food-feed poisoning and fighting back antibiotic resistance. In this study, we investigated the antimicrobial properties of lingonberry (Vaccinium vitis-idaea), raspberry (Rubus idaeus) and blackberry (Rubus fruticosus) crude and ethanolic extracts prepared from fruits obtained from the spontaneous flora of Eastern Carpathian Mountains situated in Transylvania. The antimicrobial effect of crude and alcoholic extracts were assessed on four Gram-negative, five Gram-positive bacteria and one yeast species using the agar diffusion method. The studied bacteria can cause food or feed spoilage and foodborne diseases. Our results indicate the significant inhibitory effect of lingonberry extracts in the case of Gram-negative bacteria like Proteus vulgaris and Salmonella Hartford, while among Gram-positive bacteria the strongest inhibitory effect was observed for Bacillus species like B. cereus, B. subtilis, B. mojavensis and Micrococcus luteus. The raspberry and blackberry extracts featured milder inhibitory effects in the case of the studied bacteria species. Furthermore, we have studied the crude or ethanolic extract combinations associated antimicrobial effects synergistic/additive or antagonistic properties. Interestingly, the triple and double ethanolic extract mixes had stronger antimicrobial properties, whereas the crude extract mixes showed relatively reduced effects, if any. Our results indicate that the antimicrobial activity of studied fruit extracts obtained from wild berries can vary upon the applied extraction method and their combination formulae, so that all these considerations must be taken into account when such fruit extracts are considered for foodstuff development.


2021 ◽  
Vol 34 (1) ◽  
pp. 42-52
Author(s):  
S. Tamilvanan

The synthesis and characterization of novel antimony(III) dithiocarbamate complexes tris(N-furfuryl- N-propyldithiocarbamato-S,S′)antimony(III) (1) and tris(N-furfuryl-N-butyldithiocarbamato- S,S′)antimony(III) (2) have been characterized by elemental analysis, FT-IR, NMR (1H and 13C) spectra and antimicrobial studies. The characteristic thioureide (νC-N) bands occur at 1462 and 1475 cm-1 for complex 1 and 2, respectively. The theoretical calculations of the complexes have been carried out by density functional theory (DFT). The FMOs, MEP, Mulliken charge distribution and chemical activity parameters of the optimized structure have been calculated at the same level of theory. The MEP structure indicated that the positive and negative potential sites are around hydrogen atoms and electronegative atoms of the studied complexes, respectively. The Agar-well diffusion method were used to study the antimicrobial activity of the complexes against two Gram-positive bacteria (Klebsiella pneumoniae and Staphylococcus aureus), two Gram-negative bacteria (Escherichia coli and Vibrio cholera) and two fungal organisms (Candida albicans and Aspergillus niger).


2021 ◽  
pp. 088391152110142
Author(s):  
Velu Gomathy ◽  
Venkatesan Manigandan ◽  
Narasimman Vignesh ◽  
Aavula Thabitha ◽  
Ramachandran Saravanan

Biofilms play a key role in infectious diseases, as they may form on the surface and persist after treatment with various antimicrobial agents. The Staphylococcus aureus, Klebsiella pneumoniae, S. typhimurium, P. aeruginosa, and Escherichia coli most frequently associated with medical devices. Chitosan sulphate from marine litter (SCH-MW) was extracted and the mineral components were determined using atomic absorption spectroscopy (AAS). The degree of deacetylation (DA) of SCH was predicted 50% and 33.3% in crab and shrimp waste respectively. The elucidation of the structure of the SCH-MW was portrayed using FT-IR and 1H-NMR spectroscopy. The molecular mass of SCH-MW was determined with Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF). The teratogenicity of SCH-MW was characterized by the zebrafish embryo (ZFE) model. Antimicrobial activity of SCH-MW was tested with the agar well diffusion method; the inhibitory effect of SCH-MW on biofilm formation was assessed in 96 flat well polystyrene plates. The result revealed that a low concentration of crab-sulfated chitosan inhibited bacterial growth and significantly reduced the anti-biofilm activity of gram-negative and gram-positive bacteria relatively to shrimp. It is potentially against the biofilm formation of pathogenic bacteria.


2020 ◽  
Vol 83 (1) ◽  
pp. 19-25
Author(s):  
Suntini Suntini ◽  
Anastasia Wheni Indrianingsih ◽  
Harjono Harjono

Recently, a wound healing from natural composite with excellent properties is in a high demand. In this study, a novel composite of bacterial cellulose made from Siwalan sap (Borassus flabellifer) was achieved. Siwalan is a common plant in Java Island of Indonesia and the application is very limited for beverage only. This study aims to determine the effect of the AgNO3/NaBH4 concentration ratio in the development of Ag-BC composites and its antibacterial properties from Siwalan sap. Ag-BC composites were prepared by impregnating the silver solution into the BC matrix through the reduction process with NaBH4. Characterization of Ag-BC composites conducted using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX). Antibacterial assay was performed using disc diffusion method against Salmonella typhimurium (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. The characterization of Ag-BC composite shows the nanostructure of BC with a length of fiber around 35-60 nm in width. The SEM-EDX micrograph showed that silver particles were impregnated into the BC matrix. Antibacterial activity test results showed that the Ag-BC composite had the ability to inhibit the bacteria S. typhimurium and S. aureus with good inhibition. This result showed the potential application of Ag-BC composite from Siwalan plant as a natural material for medical and pharmaceutical purpose, especially as an antibacterial agent.


2019 ◽  
Vol 31 (12) ◽  
pp. 2821-2826 ◽  
Author(s):  
Seema A. Gosavi ◽  
Dattatray H. Nandal ◽  
Sarita S. Pawar

Novel isoxazoline derivatives were synthesized by condensation of substituted acetophenones with aldehyde in presence of alcoholic NaOH to get intermediate chalcones, which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazoline derivatives. The latter were refluxed separately with isonicotinic acid hydrazide and sulphanilamide in presence of formaldehyde for 6-10 h to afford corresponding Mannich bases. The structures of synthesized compounds were established on the basis of melting point, TLC, IR, 1H NMR and HRMS. Antimycobacterial activity of compounds (3a-j) were assessed against M. tuberculosis (vaccine strain, H37 Rv strain) ATCC27294 using microplate Alamar Blue assay (MABA). Further the derivatives were evaluated for the antibacterial activity against Gram positive bacteria S. aureus (ATCC 9144), S. epidemidis (ATCC12228) and Gram negative bacteria E. coli (ATCC 25922), Klebsiella (ATCC 4352), while antifungal activity against A. flavus (ATCC 9643) and A. niger (ATCC 16404) by using agar well diffusion method using ciprofloxacin and fluconazole as standards, respectively. The results of antimicrobial studies showed that some of the derivatives posses mild to moderate biological activity as compared to standard.


1990 ◽  
Vol 267 (2) ◽  
pp. 509-515 ◽  
Author(s):  
N M Hooper ◽  
J Hryszko ◽  
A J Turner

Aminopeptidase P (EC 3.4.11.9) was solubilized from pig kidney membranes with bacterial phosphatidylinositol-specific phospholipase C (PI-PLC) and then purified by a combination of anion-exchange and hydrophobic-interaction chromatographies. Contaminating peptidase activities were removed by selective affinity chromatography. The purified enzyme was apparently homogeneous on SDS/PAGE with an Mr of 91,000. Enzymic deglycosylation revealed that aminopeptidase P is a glycoprotein, with up to 25% by weight of the protein being due to the presence of N-linked sugars. The phospholipase-solubilized aminopeptidase P was recognized by an antiserum to the cross-reacting determinant (CRD) characteristic of the glycosyl-phosphatidylinositol anchor. This recognition was abolished by mild acid treatment or deamination with HNO2, indicating that the CRD was due exclusively to the inositol 1,2-cyclic phosphate ring epitope generated by the action of PI-PLC. The activity of aminopeptidase P was inhibited by chelating agents and was stimulated by Mn2+ or Co2+ ions, confirming the metallo-enzyme nature of this peptidase. Selective inhibitors of other aminopeptidases (actinonin, amastatin, bestatin and puromycin) had little or no inhibitory effect.


1999 ◽  
Vol 62 (5) ◽  
pp. 543-546 ◽  
Author(s):  
J. FERNÁNDEZ ◽  
A. F. MOHEDANO ◽  
P. GAYA ◽  
M. MEDINA ◽  
M. NUÑEZ

Three proteinases were isolated from culture medium of Pseudomonas fluorescens INIA 745 and purified to homogeneity by a combination of Phenyl-Sepharose, DEAE-Sepharose, and Sephadex G-100 chromatography. Optimal temperature for enzymatic activity was 45°C for all three proteinases. The pH optimum of proteinases I and II was found to be 7.0, while that of proteinase III was 8.0. Divalent metal ions like Cu2+, Co2+, Zn2+, Fe2+, and Hg2+ were inhibitory to proteinase activity while Ca2+, Mg2+, and Mn2+ had little or no inhibitory effect. The three enzymes were strongly inhibited by EDTA and 1,10-phenantroline and partially by cysteine. The three enzymes are metalloproteinases since they were inhibited by chelators and reactivated by Co2+, Mn2+, Cu2+, and Zn2+. The Km values of proteinases I, II, and III for casein were calculated to be 3.2, 2.6, and 5.2 mg/ml, respectively. Proteinases II and III rapidly degraded β-casein, with preference to αs1-casein, whereas proteinase I hydrolyzed both casein fractions at a slow rate.


1998 ◽  
Vol 61 (10) ◽  
pp. 1330-1335 ◽  
Author(s):  
T. PADGETT ◽  
I. Y. HAN ◽  
P. L. DAWSON

Lysozyme and nisin are both antimicrobial proteins effective against gram-positive bacteria. The use of these antimicrobials in combination with chelating agents displays increased effectiveness against gram-negative bacteria. Packaging films with lysozyme or nisin incorporated into the film structure were tested separately for inhibition against Lactobacillus plantarian. Both lysozyme and nisin were used in combination with EDTA in films and were evaluated for inhibition against Escherichia coli. Two packaging film-forming methods were used to incorporate lysozyme or nisin into biodegradable protein films to determine if antimicrobial properties could be induced in the film. Heat-press and casting methods were used to produce films made from soy protein and corn zein. Circular samples were cut from the finished films, which were then placed on a bacterial lawn, incubated, and measured for any zones of inhibition. Both cast and heat-press films with added lysozyme or nisin formed excellent films and exhibited inhibition of bacterial growth. The lysozyme and nisin retained their bacteriocidal properties throughout both the heat-press and cast film-forming processes. The cast films exhibited larger inhibitory zones, as compared to the heat-press films, when the same levels of lysozyme or nisin were incorporated. L. plantarum was inhibited by films containing nisin or lysozyme. The addition of EDTA increased the inhibitory effect of films against E. coli.


1999 ◽  
Vol 276 (6) ◽  
pp. G1435-G1441 ◽  
Author(s):  
Tomohiro Terada ◽  
Kyoko Sawada ◽  
Hideyuki Saito ◽  
Yukiya Hashimoto ◽  
Ken-Ichi Inui

The apical H+-coupled peptide transporter (PEPT1) and basolateral peptide transporter in human intestinal Caco-2 cells were functionally compared by the characterization of [14C]glycylsarcosine transport. The glycylsarcosine uptake via the basolateral peptide transporter was less sensitive to medium pH than uptake via PEPT1 and was not transported against the concentration gradient. Kinetic analysis indicated that glycylsarcosine uptake across the basolateral membranes was apparently mediated by a single peptide transporter. Small peptides and β-lactam antibiotics inhibited glycylsarcosine uptake by the basolateral peptide transporter, and these inhibitions were revealed to be competitive. Comparison of the inhibition constant values of various β-lactam antibiotics between PEPT1 and the basolateral peptide transporter suggested that the former had a higher affinity than the latter. A histidine residue modifier, diethyl pyrocarbonate, inhibited glycylsarcosine uptake by both transporters, although the inhibitory effect was greater on PEPT1. These findings suggest that a single facilitative peptide transporter is expressed at the basolateral membranes of Caco-2 cells and that PEPT1 and the basolateral peptide transporter cooperate in the efficient transepithelial transport of small peptides and peptidelike drugs.


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