New Alkenylresorcinols with Cytotoxic and Antimicrobial Activities from the Leaves of Embelia schimperi

Planta Medica ◽  
2020 ◽  
Vol 86 (17) ◽  
pp. 1298-1303
Author(s):  
Tatiana Arlette M. Togue ◽  
Blanche Laure Ndontsa ◽  
Gabin Thierry M. Bitchagno ◽  
Anja Schüffler ◽  
Till Opatz ◽  
...  
Keyword(s):  
Antimicrobial Properties ◽  
Antimicrobial Activities ◽  
Spectroscopic Techniques ◽  
Ongoing Research ◽  
Phytochemical Study ◽  
Phenolic Lipids ◽  
Cervical Cancer Cells ◽  
Hela S3 ◽  
Human Cervical Cancer Cells

AbstractA phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1 – 3, together with the known analogs 4 – 7. Their structures were established by a combination of spectroscopic techniques. Compounds 1 – 7 exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.

Isolation and Characterization of Soil Myxobacteria from Nepal

2019 ◽  
Vol 24 (2) ◽  
pp. 7-16
Author(s):  
Nabin Rana ◽  
Saraswoti Khadka ◽  
Bishnu Prasad Marasini ◽  
Bishnu Joshi ◽  
Pramod Poudel ◽  
...  
Keyword(s):  
Sequence Similarity ◽  
Antimicrobial Properties ◽  
Antimicrobial Activities ◽  
Rrna Gene ◽  
Isolation And Characterization ◽  
The Family ◽  
Global Concern ◽  
Bacteria And Fungi ◽  
Antimicrobial Metabolites

 Realizing myxobacteria as a potential source of antimicrobial metabolites, we pursued research to isolate myxobacteria showing antimicrobial properties. We have successfully isolated three strains (NR-1, NR-2, NR-3) using the Escherichia coli baiting technique. These isolates showed typical myxobacterial growth characteristics. Phylogenetic analysis showed that all the strains (NR-1, NR-2, NR-3) belong to the family Archangiaceae, suborder Cystobacterineae, and order Myxococcales. Furthermore, 16S rRNA gene sequence similarity searched through BLAST revealed that strain NR-1 showed the closest similarity (91.8 %) to the type strain Vitiosangium cumulatum (NR-156939), NR-2 showed (98.8 %) to the type of Cystobacter badius (NR-043940), and NR-3 showed the closest similarity (83.5 %) to the type of strain Cystobacter fuscus (KP-306730). All isolates showed better growth in 0.5-1 % NaCl and pH around 7.0, whereas no growth was observed at pH 9.0 and below 5.0. All strains showed better growth at 32° C and hydrolyzed starch, whereas casein was efficiently hydrolyzed by NR-1 and NR-2. Besides, preliminary antimicrobial tests from crude extracts showed activities against Gram-positive, Gram-negative bacteria, and fungi. Our findings suggest that the arcane soil habitats of Nepal harbor myxobacteria with the capability to produce diverse antimicrobial activities that may be explored to overcome the rapidly rising global concern about antibiotic resistance.

Characterization of microemulsions formulated from naturally and chemically extracted oils from Cocos nucifera Linne

2020 ◽  
Vol 16 (1) ◽  
pp. 39-48
Author(s):  
O.A. Adetunji ◽  
B. Adesanwo ◽  
O.A. Odeniyi
Keyword(s):  
Castor Oil ◽  
Cocos Nucifera ◽  
Antimicrobial Properties ◽  
Coconut Oil ◽  
Tween 80 ◽  
Antimicrobial Activities ◽  
Oil Extraction ◽  
Hot Water ◽  
Copper Zinc

Background: Oil derived from Cocos nucifera Linne (CNL) has been used in formulating creams; however, its use in formulation of microemulsion is not well documented in literature.Objective: Oils obtained from CNL were characterized, used in the formulation of microemulsions and were evaluated for their antimicrobial properties in comparison with Castor oil BP (CO) and commercially available coconut oil (CACO).Methodology: Oil from CNL was extracted by maceration in hot – water and petroleum ether to yield naturally extracted oil (NEO) and chemically extracted oil (CEO) respectively. The NEO and CEO were used in formulating microemulsions containing pre-determined ratios (3:7, 1:1, 9:1) of oil to surfactant mix (Smix) [containing polyethylene glycol: Tween 80® at ratio 2:1] Characterization of NEO, CEO and microemulsions were carried out using elemental constituents, rheology, physico-and phyto-chemical analysis, thermal stability and antimicrobial profiles as parameters. Statistical analysis was done using ANOVA at p<0.05Results: The NEO and CEO contained antraquinones and terpenoids, but were devoid of lead, copper, zinc, alkaloids, saponins, cardiac glycosides and flavonoids. Viscosity profiles were in the order CO>CEO>CACO>NEO. The microemulsions were in the size range 54.24±0.26-89.08±0.07 μm. Microemulsions of oil:Smix (3:7) were the most stable. Inhibition ranking was Candida sp.D25 (CEO:Smix>CACO: Smix>NEO: Smix>NEO>CO>CEO), Candida sp.D33 (CEO = CO>CACO: Smix=NEO>CEO:Smix=NEO:Smix), Staphylococcus sp.DS2 (NEO>CO>CACO:Smix>NEO: Smix>CEO: Smix=CEO) and Pseudomonas sp.DP8 (NEO:Smix>CO>CACO:Smix>CEO:Smix=NEO > CEO).Conclusion: Oil derived from CNL has good potentials as an excipient in the formulation of microemulsions and the method of oil extraction had a significant effect on the antimicrobial activities and on the microemulsions formulated using the oils. Keywords: Coconut oil, extraction method, castor oil, microemulsions, antimicrobial properties.

Synthesis and Characterization of Chemical Structures, Thermal Decomposition and Biological Properties of Novel Copper (II) Bio- Based Surfactants

2020 ◽  
Vol 10 (3) ◽  
pp. 213-228
Author(s):  
Asha Meena ◽  
Rashmi Sharma ◽  
Vandana Sukhadia
Keyword(s):  
Staphylococcus Aureus ◽  
Thermal Degradation ◽  
Edible Oils ◽  
Waste Water Treatment ◽  
Antimicrobial Properties ◽  
Antimicrobial Activities ◽  
Biological Properties ◽  
Synthesis And Characterization ◽  
Chemical Structures

Background: Thermal degradation has attracted the attention of scientific community throughout the world due to its multiple applications in environment, energy, waste water treatment, pollution control, green chemistry, etc. Objective: The present work deals with the study of synthesis and characterization of thermal and biological properties of novel copper complex. Methods: Chemical structures of copper (II) sesame 2-amino-6-ethoxy benzothiazole complex were confirmed by IR, NMR, and ESR techniques. Thermal and biological properties were analysed by Thermogravimetry (TGA) and antimicrobial activity determination against Staphylococcus aureus. Results: The TGA study reveals that copper (II) sesame 2-amino-6-ethoxy benzothiazole complex undergoes stepwise thermal degradation of ligand-soap bond of complex and unsaturated and saturated fatty acid components of edible oils. The complex exhibit significant antimicrobial activities against Staphylococcus aureus. Conclusion: This study provides relevant basic information on the thermal and antimicrobial properties of new copper (II) bio-based surfactants, as well as an explicit relationship structure-biological activity for their potential use as safe and green chemicals.

scholarly journals Synthesis and characterization of new 2-amino-4-(substituted phenyl)-6-(7’’-methoxy, 3’’,4’’-dihydro, 2’’,2’’-dimethyl-2hbenzopyran) pyrimidines and their bio evaluation

2012 ◽  
Vol 77 (7) ◽  
pp. 859-866
Author(s):  
Y.L.N. Murthy ◽  
Padma Suhasini ◽  
Jha Anjali
Keyword(s):  
Bacillus Pumilus ◽  
Antimicrobial Properties ◽  
Spectroscopic Techniques ◽  
Gram Negative Bacteria ◽  
Antibacterial And Antifungal Activities ◽  
Ft Ir ◽  
Inhibition Zones ◽  
Antibacterial And Antifungal ◽  
Ir Spectroscopic

A series of eight novel 2-amino-4-(substituted phenyl)-6-(7"- methoxy, 3",4"-dihydro, 2",2"-dimethyl-2H-benzopyran) pyrimidines were designed and synthesized by utilizing benzene-1,3-diol as starting material. The structures of the isolated products (6a-h) were established through 1HNMR, 13C-NMR, and FT-IR spectroscopic techniques and elemental analysis. The synthesized compounds were utilized for screening antimicrobial properties against gram positive (Bacillus pumilus, Bacillus subtilis, Streptococcus faecalis), gram negative bacteria (Enterococcus faecalis, Escheria coli, Proteus vulgaris) and fungi (Pencillian expasom, Aspergillus niger, Candida albicans) using Ampicillin and Ketoconazole. Most of the compounds showed moderate to high antibacterial and antifungal activities against studied strains with inhibition zones between 8 and 30 mm.

scholarly journals A novel horse α-defensin: gene transcription, recombinant expression and characterization of the structure and function

2007 ◽  
Vol 407 (2) ◽  
pp. 267-276 ◽  
Author(s):  
Oliver Bruhn ◽  
Petra Regenhard ◽  
Matthias Michalek ◽  
Sven Paul ◽  
Christoph Gelhaus ◽  
...  
Keyword(s):  
Small Intestine ◽  
Recombinant Expression ◽  
Paneth Cell ◽  
Lethal Dose ◽  
Antimicrobial Properties ◽  
Antimicrobial Activities ◽  
Minimal Bactericidal Concentration ◽  
Transcription Analysis ◽  
And Function

Defensins are a predominant class of antimicrobial peptides, which act as endogenous antibiotics. Defensins are classified into three distinct sub-families: θ-, β-, and α-defensins. Synthesis of α-defensin has been confirmed only in primates and glires to date and is presumably unique for a few tissues, including neutrophils and Paneth cells of the small intestine. Antimicrobial activities of these peptides were shown against a wide variety of microbes including bacteria, fungi, viruses and protozoan parasites. In the present study, we report the characterization of the equine α-defensin DEFA (defensin α) 1. Transcription analysis revealed that the transcript of the gene is present in the small intestine only. An alignment with known α-defensins from primates and glires displayed a homology with Paneth-cell-specific α-defensins. DEFA1 was recombinantly expressed in Escherichia coli and subsequently analysed structurally by CD and molecular modelling. To examine the antimicrobial properties, a radial diffusion assay was performed with 12 different micro-organisms and the LD90 (lethal dose killing ≥90% of target organism) and MBC (minimal bactericidal concentration) values were examined. DEFA1 showed an antimicrobial activity against different Gram-positive and Gram-negative bacteria and against the yeast Candida albicans. Using viable bacteria in combination with a membrane-impermeable fluorescent dye, as well as depolarization of liposomes as a minimalistic system, it became evident that membrane permeabilization is at least an essential part of the peptide's mode of action.

Characterization of intergranular cuprous oxide in polycrystalline YBa2Cu3O7-x

1988 ◽  
Vol 46 ◽  
pp. 880-881
Author(s):  
Bradley L. Thiel ◽  
Chan Han R. P. ◽  
Kurosky L. C. Hutter ◽  
I. A. Aksay ◽  
Mehmet Sarikaya
Keyword(s):  
Grain Boundary ◽  
Cuprous Oxide ◽  
Room Temperature ◽  
Boundary Phase ◽  
Spectroscopic Techniques ◽  
Transition Width ◽  
Practical Applications ◽  
Thin Foils ◽  
Superconducting Oxides

The identification of extraneous phases is important in understanding of high Tc superconducting oxides. The spectroscopic techniques commonly used in determining the origin of superconductivity (such as RAMAN, XPS, AES, and EXAFS) are surface-sensitive. Hence a grain boundary phase several nanometers thick could produce irrelevant spectroscopic results and cause erroneous conclusions. The intergranular phases present a major technological consideration for practical applications. In this communication we report the identification of a Cu2O grain boundary phase which forms during the sintering of YBa2Cu3O7-x (1:2:3 compound).Samples are prepared using a mixture of Y2O3. CuO, and BaO2 powders dispersed in ethanol for complete mixing. The pellets pressed at 20,000 psi are heated to 950°C at a rate of 5°C per min, held for 1 hr, and cooled at 1°C per min to room temperature. The samples show a Tc of 91K with a transition width of 2K. In order to prevent damage, a low temperature stage is used in milling to prepare thin foils which are then observed, using a liquid nitrogen holder, in a Philips 430T at 300 kV.

Synthesis and Characterization of Potential and Degraded Impurities of Regadenoson

2020 ◽  
Vol 16 (8) ◽  
pp. 1130-1139
Author(s):  
Singaram Sathiyanarayanan ◽  
Chidambaram Subramanian Venkatesan ◽  
Senthamaraikannan Kabilan
Keyword(s):  
Mass Spectra ◽  
Degradation Products ◽  
Hplc Method ◽  
Forced Degradation ◽  
Spectroscopic Techniques ◽  
A2a Adenosine Receptor ◽  
Degradation Study ◽  
Related Substances ◽  
Adenosine Receptor Agonist

Background: Regadenoson is an A2A adenosine receptor agonist that is a coronary vasodilator and commonly used as a pharmacologic cardiac stressing agents. Methods: HPLC method was used for the analysis of related substances. The degraded impurities during the process were isolated and characterized by IR, Mass and NMR spectral analysis. Results: Forced degradation study of regadenoson under conditions of hydrolysis (neutral, acidic and alkaline) and oxidations suggested in the ICH Q1A(R2) was accomplished. The drug showed significant degradation under all the above conditions. On the whole, five novel degradation products were found under diverse conditions along with process related impurities which were not reported earlier. Conclusion: All the degradation products were well characterized by using advanced spectroscopic techniques like IR, 1H NMR, 13C NMR and Mass spectra. The identification of these impurities will be productive for the quality control during the production and stability behavior of the regadenoson drug substance.

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