This study describes a sago starch-based film by incorporation of cinnamon essential oil (CEO) and nano titanium dioxide (TiO2-N). Different concentrations (i.e., 0%, 1%, 3%, and 5%, w/w) of TiO2-N and CEO (i.e., 0%, 1%, 2%, and 3%, v/w) were incorporated into sago starch film, and the physicochemical, barrier, mechanical, and antimicrobial properties of the bionanocomposite films were estimated. Incorporation of CEO into the sago starch matrix increased oxygen and water vapor permeability of starch films while increasing TiO2-N concentration decreased barrier properties. Moisture content also decreased from 12.96% to 8.04%, solubility in water decreased from 25% to 13.7%, and the mechanical properties of sago starch films improved. Sago starch bionanocomposite films showed excellent antimicrobial activity against Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus. Results also showed that incorporation of TiO2-N and CEO had synergistic effects on functional properties of sago starch films. In summary, sago starch films incorporated with both TiO2-N and CEO shows potential application for active packaging in food industries such as fresh pistachio packaging.
Artocarpus altilis (breadfruit) pulp, peel and whole fruit were extracted with various solvents such as hexane, dichloromethane (DCM) and methanol. The antioxidant activity of these extracts were examined using the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test. IC50 was 55 ± 5.89 μg/ml for the pulp part of methanol extract. In the β-carotene bleaching assay, the antioxidant activity was 90.02 ± 1.51 % for the positive control (Trolox) and 88.34 ± 1.31 % for the pulp part of the fruit methanol extract. The total phenolic content of the crude extracts was determined using the Folin-Ciocalteu procedure; methanol pulp part demonstrated the highest phenol content value of 781 ± 52.97 mg GAE/g of dry sample. While the total flavonoid content was determined using the aluminium chloride colorimetric assay, the highest value of 6213.33 ± 142.22 mg QE/g was indicated by pulp part of the fruit methanol extract. The antimicrobial activity of the crude extracts was tested using disc diffusion method against pathogenic microorganisms: Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus, Salmonella typhimurium, Escherichia coli, Klebsiella pneumonia and Candida albicans. Methanol extract of pulp part was recorded to have the highest zone of inhibition against Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) and MBC/minimal fungicidal concentration (MFC) for the extracts were also determined using the microdilution method ranging from 4000 to 63 μg/ml against pathogenic microbes. The MBC/MFC values varied from 250 to 4000 μg/ml. A correlation between antioxidant activity assays, antimicrobial activity and phenolic content was established. The results shows that the various parts of A. altilis fruit extracts promising antioxidant activities have potential bioactivities due to high content of phenolic compounds.
Polymeric nanoparticles are widely used for drug delivery due to their biodegradability property. Among the wide array of polymers, chitosan has received growing interest among researchers. It was widely used as a vehicle in polymeric nanoparticles for drug targeting. This review explored the current research on the antimicrobial activity of chitosan nanoparticles (ChNP) and the impact on the clinical applications. The antimicrobial activities of ChNP were widely reported against bacteria, fungi, yeasts and algae, in both in vivo and in vitro studies. For pharmaceutical applications, ChNP were used as antimicrobial coating for promoting wound healing, preventing infections and combating the rise of infectious disease. Besides, ChNP also exhibited significant inhibitory on foodborne microorganisms, particularly on fruits and vegetables. It is noteworthy that ChNP can be also applied to deliver antimicrobial drugs, which further enhance the efficiency and stability of the antimicrobial agent. The present review addresses the potential antimicrobial applications of ChNP from these few aspects.
A series of 1,3-thiazolidin-4-one derivatives were prepared by the reaction of respective aromatic amine, aromatic aldehyde, and thioglycolic acid in dry benzene/toluene. The newly synthesized compounds were characterized on the basis of elemental analysis, IR, (1) HNMR, and mass spectra. The newly synthesized final compounds were evaluated for their in vitro antibacterial, antifungal, and anti-viral activities. Preliminary results indicated that some of the compounds demonstrated antibacterial activity in the range of 7-13 μg/mL, antifungal activity in the range of 13-17 μg/mL, comparable with the standard drugs, ciprofloxacin and fluconazole. Structure-activity relationship studies revealed that the nature of the substituents at the 2 and 3 positions of the thiazolidinone nucleus had a significant impact on the in vitro antimicrobial and anti-viral activity of these classes of agents.
The in vitro cytotoxicity tests on the extracts of Mesua beccariana, M. ferrea, and M. congestiflora against Raji, SNU-1, HeLa, LS-174T, NCI-H23, SK-MEL-28, Hep-G2, IMR-32, and K562 were achieved using MTT assay. The methanol extracts of Mesua beccariana showed its potency towards the proliferation of B-lymphoma cell (Raji). In addition, only the nonpolar to semipolar extracts (hexane to ethyl acetate) of the three Mesua species indicated cytotoxic effects on the tested panel of human cancer cell lines. Antioxidant assays were evaluated using DPPH scavenging radical assay and Folin-Ciocalteu method. The methanol extracts of M. beccariana and M. ferrea showed high antioxidant activities with low EC₅₀ values of 12.70 and 9.77 μg/mL, respectively, which are comparable to that of ascorbic acid (EC₅₀ = 5.62 μg/mL). Antibacterial tests were carried out using four Gram positive and four Gram negative bacteria on Mesua beccariana extracts. All the extracts showed negative results in the inhibition of Gram negative bacteria. Nevertheless, methanol extracts showed some activities against Gram positive bacteria which are Bacillus cereus, methicillin-sensitive Staphylococcus aureus (MSSA), and methicillin-resistant Staphylococcus aureus (MRSA), while the hexane extract also contributed some activities towards Bacillus cereus.
The family Sterculiaceae is one of the most important families among flowering plants. Many of its members demonstrate medicinal properties and have been used for the treatment of various ailments and wounds. A wide range of compounds including alkaloids, phenyl propanoids, flavonoids, terpenoids and other types of compounds including hydrocarbons, sugars, quinones, phenolic acids, lactones, lignans, amine and amides have been isolated from several species in this family. Few studies have reported that some extracts and single compounds isolated from this family exhibited several biological activities, such as antimicrobial, anti-inflammatory, antioxidant and cytotoxic activities. The present review is an effort to provide information about the traditional uses, phytochemistry and pharmacology of species from family Sterculiaceae, and to uncover the gaps and potentials requiring further research opportunities regarding the chemistry and pharmacy of this family.
The present study describes palladium-catalyzed one pot Suzuki cross-coupling reaction to synthesize a series of novel pyridine derivatives 2a-2i, 4a-4i. In brief, Suzuki cross-coupling reaction of 5-bromo-2-methylpyridin-3-amine (1) directly or via N-[5-bromo-2-methylpyridine-3-yl]acetamide (3) with several arylboronic acids produced these novel pyridine derivatives in moderate to good yield. Density functional theory (DFT) studies were carried out for the pyridine derivatives 2a-2i and 4a-4i by using B3LYP/6-31G(d,p) basis with the help of GAUSSIAN 09 suite programme. The frontier molecular orbitals analysis, reactivity indices, molecular electrostatic potential and dipole measurements with the help of DFT methods, described the possible reaction pathways and potential candidates as chiral dopants for liquid crystals. The anti-thrombolytic, biofilm inhibition and haemolytic activities of pyridine derivatives were also investigated. In particular, the compound 4b exhibited the highest percentage lysis value (41.32%) against clot formation in human blood among all newly synthesized compounds. In addition, the compound 4f was found to be the most potent against Escherichia coli with an inhibition value of 91.95%. The rest of the pyridine derivatives displayed moderate biological activities.
This work aims to shed light in the fabrication of poly(3-hydroxybutyrate-co-44%-4-hydroxybutyrate)[P(3HB-co-44%4HB)]/chitosan-based silver nanocomposite material using different contents of silver nanoparticle (SNP); 1-9 wt%. Two approaches were applied in the fabrication; namely solvent casting and chemical crosslinking via glutaraldehyde (GA). A detailed characterization was conducted in order to yield information regarding the nanocomposite material. X-ray diffraction analysis exhibited the nature of the three components that exist in the nanocomposite films: P(3HB-co-4HB), chitosan, and SNP. In term of mechanical properties, tensile strength, and elongation at break were significantly improved up to 125% and 22%, respectively with the impregnation of the SNP. The melting temperature of the nanocomposite materials was increased whereas their thermal stability was slightly changed. Scanning electron microscopy images revealed that incorporation of 9 wt% of SNP caused agglomeration but the surface roughness of the material was significantly improved with the loading. Staphylococcus aureus and Escherichia coli were completely inhibited by the nanocomposite films with 7 and 9 wt% of SNP, respectively. On the other hand, degradation of the nanocomposite materials outweighed the degradation of the pure copolymer. These bioactive and biodegradable materials stand a good chance to serve the vast need of biomedical applications namely management and care of wound as wound dressing.
This study investigates the complete molecular characterization including bioinformatics characterization, gene expression, synthesis of N and C terminal peptides and their antimicrobial activity of the core histone 4 (H4) from freshwater giant prawn Macrobrachium rosenbergii (Mr). A cDNA encoding MrH4 was identified from the constructed cDNA library of M. rosenbergii during screening and the sequence was obtained using internal sequencing primers. The MrH4 coding region possesses a polypeptide of 103 amino acids with a calculated molecular weight of 11kDa and an isoelectric point of 11.5. The bioinformatics analysis showed that the MrH4 polypeptide contains a H4 signature at (15)GAKRH(19). Multiple sequence alignment of MrH4 showed that the N-terminal (21-42) and C-terminal (87-101) antimicrobial peptide regions and the pentapeptide or H4 signature (15-19) are highly conserved including in humans. The phylogenetic tree formed two separate clades of vertebrate and invertebrate H4, wherein MrH4 was located within the arthropod monophyletic clade of invertebrate H4 groups. Three-dimensional model of MrH4 was established using I-TASSER program and the model was validated using Ramachandran plot analysis. Schiffer-Edmundson helical wheel modeling was used to predict the helix propensity of N (21-42) and C (87-101) terminal derived Mr peptides. The highest gene expression was observed in gills and is induced by viral [white spot syndrome baculovirus (WSBV) and M. rosenbergii nodovirus (MrNV)] and bacterial (Aeromonas hydrophila and Vibrio harveyi) infections. The N and C terminal peptides were synthesized and their antimicrobial and hemolytic properties were examined. Both peptides showed activity against the tested Gram negative and Gram positive bacteria; however, the highest activity was noticed against Gram negative bacteria. Among the two peptides used in this study, C-terminal peptide yielded better results than the N-terminal peptide. Therefore, C terminal peptide can be recommended for the development of an antimicrobial agent.
The aim of the study was to determine the chemical profile, antioxidant properties and antimicrobial activities of Heterotrigona itama bee bread from Malaysia. The pH, presence of phytochemicals, antioxidant properties, total phenolic content (TPC) and total flavonoid content (TFC), as well as antimicrobial activities, were assessed. Results revealed a decrease in the pH of bee bread water extract (BBW) relative to bee bread ethanolic extract (BBE) and bee bread hot water extract (BBH). Further, alkaloids, flavonoids, phenols, tannins, saponins, terpenoids, resins, glycosides and xanthoproteins were detected in BBW, BBH and BBE. Also, significant decreases in TPC, TFC, DPPH activity and FRAP were detected in BBW relative to BBH and BBE. We detected phenolic acids such as gallic acid, caffeic acid, trans-ferulic acid, trans 3-hydroxycinnamic acid and 2-hydroxycinnamic acid, and flavonoids such as quercetin, kaempferol, apigenin and mangiferin in BBE using high-performance liquid chromatography analysis. The strongest antimicrobial activity was observed in Klebsilla pneumonia (MIC50 1.914 µg/mL), followed by E. coli (MIC50 1.923 µg/mL), Shigella (MIC50 1.813 µg/mL) and Salmonella typhi (MIC50 1.617 µg/mL). Bee bread samples possess antioxidant and antimicrobial properties. Bee bread contains phenolic acids and flavonoids, and could be beneficial in the management and treatment of metabolic diseases.
The essential oils obtained by hydrodistillation of the unripe and ripe fruits of Alpinia mutica Roxb. and Alpinia latilabris Ridl. were analysed by capillary GC and GC-MS. The oils were principally monoterpenic in nature. The unripe and ripe fruit oils of A. mutica were characterized by camphor (21.0% and 15.8%), camphene (16.6% and 10.2%), β-pinene (8.6% and 13.5%), and trans,trans-farnesol (8.0% and 11.2%), respectively. The oils of the unripe and ripe fruits were moderately active against Staphylococcus aureus, Bacillus subtilis, Trichophyton mentagrophytes, and Trichophyton rubrum. 1,8-Cineole (34.2% and 35.9%) and β-pinene (20.2% and 19.0%) were the two most abundant components in the unripe and ripe fruit oils of A. latilabris. The oil of the unripe fruits elicits moderate activity against Staphylococcus aureus and Trichophyton mentagrophytes while Candida glabrata was moderately sensitive to the oil of the ripe fruits.
The essential oils from the leaves and rhizomes of Alpinia pahangensis Ridl., collected from Pahang, Peninsular Malaysia, were obtained by hydrodistillation, and their chemical compositions were determined by GC and GC/MS analyses. The major components of the rhizome oil were γ-selinene (11.60%), β-pinene (10.87%), (E,E)-farnesyl acetate (8.65%), and α-terpineol (6.38%), while those of the leaf oil were β-pinene (39.61%), α-pinene (7.55%), and limonene (4.89%). The investigation of the antimicrobial activity of the essential oils using the broth microdilution technique revealed that the rhizome oil of A. pahangensis inhibited five Staphylococcus aureus strains with minimum inhibitory concentration (MIC) values between 0.08 and 0.31 μg/μl, and four selected fungi with MIC values between 1.25 and 2.50 μg/μl.
Furopyridine III, namely 1-(3-amino-4-(4-(tert-butyl)phenyl)-6-(p-tolyl)furo[2,3-b]pyridin-2-yl)ethan-1-one, synthesized from 4-(4-(tert-butyl)phenyl)-2-oxo-6-(p-tolyl)-1,2-dihydropyridine-3-carbonitrile I in two steps. The title compound is characterized by NMR, MS and its X-ray structure. The molecular structure consists of planar furopyridine ring with both phenyl rings being inclined from the furopyridine scaffold to a significant different extent. There are three intramolecular hydrogen bonds within the structure. The lattice is stabilized by N-H…O, H2C-H …π and π…π intermolecular interactions leading to three-dimensional network. Compound III exhibits fluorescent properties, which are investigated. Antimicrobial potential and antioxidant activity screening studies for the title compound III and the heterocyclic derivatives, I and II, show no activity towards neither bacterial nor fungal strains, while they exhibited weak to moderate antioxidant activity compared to reference.
Previous studies have shown that hydroxytyrosol (HT) can be a potential alternative therapeutic agent for the treatment of rheumatoid arthritis (RA). However, HT is extensively metabolized following oral administration, which leads to formulating HT in a topical vehicle to prolong drug action as well as to provide a localized effect. Hidrox-6 is a freeze-dried powder derived from fresh olives and contains a high amount of HT (∼3%) and other polyphenols. Alginate bilayer films containing 5% and 10% Hidrox-6 were formulated. The films were characterized with respect to their physical, morphology, rheological properties; drug content uniformity; and in vitro drug release. Acute dermal irritancy tests and a skin sensitization study were carried out in rats. An efficacy study of the bilayer films for RA was conducted using Freund's adjuvant-induced polyarthritis rats. Animal data showed that the bilayer film formulations did not cause skin irritancy. The efficacy in vivo results showed that the Hidrox-6 bilayer films lowered the arthritic scores, paw and ankle circumference, serum IL-6 level and cumulative histological scores compared with those measured for controls. The topical Hidrox-6 bilayer films improve synovitis and inflammatory symptoms in RA and can be a potential alternative to oral RA therapy.
Green synthesis of nanomaterials finds the edge over chemical methods due to its environmental compatibility. Herein, we report green synthesis of silver nanoparticles (Ag NPs) mediated with dextran. Dextran was used as a stabilizer and capping agent to synthesize Ag NPs using silver nitrate (AgNO3) under diffused sunlight conditions.
Polysaccharides are attracting the vigil eye of researchers in order to design the green synthesis of silver nanoparticles (Ag NPs) of diverse size, shape, and application. We report an environmentally friendly method to synthesize Ag NPs where no physical reaction conditions were employed. Hydroxypropylcellulose (HPC) was used as a template nanoreactor, stabilizer, and capping agent to obtain Ag NPs. Different concentrations of AgNO3 solutions (50 mmol, 75 mmol, and 100 mmol) were mixed with a concentrated aqueous solution of HPC and the progress of the reaction was monitored by noting color changes of the reaction mixture at different reaction times for up to 24 hours. Characteristic ultraviolet-visible spectroscopy (UV/Vis) absorption bands of Ag NPs were observed in the range of 388-452 nm. The morphology of the Ag NPs was studied by scanning electron microscopy, transmission electron microscopy (TEM), and atomic force microscopy. The TEM images confirmed that the size of the Ag NPs was in the range of 25-55 nm. Powder X-ray diffraction studies showed that the crystal phase of the Ag NPs was face-centered cubic. The as-prepared Ag NPs were found to be stable, and no changes in size and morphology were observed after storage in HPC thin films over 1 year, as indicated by UV/Vis spectra. So, the present work furnishes a green and economical strategy for the synthesis and storage of stable Ag NPs. As-synthesized Ag NPs showed significant antimicrobial activity against different bacterial (Escherichia coli, Staphylococcus epidermidis, S. aureus, Bacillus subtilis, Pseudomonas aeruginosa) and fungal strains (Actinomycetes and Aspergillus niger).
The therapy of various diseases by the drugs entrapped in calixarene derivatives is gaining attraction of researchers nowadays. Calixarenes are macrocyclic nano-baskets which belong to cavitands class of host-guest chemistry. They are the marvelous hosts with distinct hydrophobic three dimensional cavities to entrap and encapsulate biologically active guest drugs. Calixarene and its derivatives develop inclusion complexes with various types of drugs and vitamins for their sustained/targeted release. Calixarene and its derivatives are used as carriers for anti-cancer, anti-convulsant, anti-hypertensive, anthelmentic, anti-inflammatory, antimicrobial and antipsychotic drugs. They are the important biocompatible receptors to improve solubility, chemical reactivity and decrease cytotoxicity of poorly soluble drugs in supramolecular chemistry. This review focuses on the calixarene and its derivatives as the state-of-the-art in host-guest interactions for important drugs. We have also critically evaluated calixarenes for the development of prodrugs.
To investigate the suitability of chitosan films prepared using two different solvents, acetic acid (Chitosan-AA) and lactic acid (Chitosan-LA), for wound dressing, in comparison with a commercial preparation, Omiderm.
In this study, we reported a complete molecular characterization including bioinformatics features, gene expression, peptide synthesis and its antimicrobial activities of an anti-lipopolysaccharide (LPS) factor (ALF) cDNA identified from the established cDNA library of freshwater prawn Macrobrachium rosenbergii (named as MrALF). The mature protein has an estimated molecular weight of 11.240 kDa with an isoelectric point of 9.46. The bioinformatics analysis showed that the MrALF contains an antimicrobial peptide (AMP) region between T54 and P77 with two conserved cysteine residues (Cys55 and Cys76) which have an anti-parallel β-sheet confirmation. The β-sheet is predicted as cationic with hydrophobic nature containing a net charge of +5. The depicted AMP region is determined to be amphipathic with a predicted hydrophobic face 'FPVFI'. A highest MrALF gene expression was observed in hemocytes and is up-regulated with virus [white spot syndrome baculovirus (WSBV)], bacteria (Aeromonas hydrophila) and Escherichia coli LPS at various time points. The LPS binding region of MrALF peptide was synthesized to study the antimicrobial property, bactericidal efficiency and hemolytic capacity. The peptide showed antimicrobial activity against both the Gram-negative and Gram-positive bacteria. The bactericidal assay showed that the peptide recognized the LPS of bacterial cell walls and binding on its substrate and thereby efficiently distinguishing the pathogens. The hemolytic activity of MrALF peptide is functioning in a concentration dependant manner. In summary, the comprehensive analysis of MrALF showed it to be an effective antimicrobial peptide and thus it plays a crucial role in the defense mechanism of M. rosenbergii.
The sol-gel/ultrasonically rout produced the novel MnS2-SiO2 nano-hetero-photocatalysts with the various ratio of MnS2. Prepared nano-catalyst were investigated in the photo-degradation of methylene blue under UV light illumination. Structural and optical attributes of as-prepared nano-catalysts were evaluated by X-ray diffraction and photoelectron spectroscopy. The morphological were studied by scanning electron microscopy-EDS, and dynamic light scattering. The diffuse reflectance spectroscopy was applied to examine the band gap energy. The Eg values of SiO2, MnS2-SiO2-0, MnS2-SiO2-1, and MnS2-SiO2-2 nanocomposites are 6.51, 3.85, 3.17, and 2.67 eV, respectively. The particle size of the SiO2 and MnS2-SiO2-1 nanocomposites were 100.0, and 65.0 nm, respectively. The crystallite size values of MnS2-SiO2-1 were 52.21 nm, and 2.9 eV, respectively. MnS2-SiO2 nano-photocatalyst was recognized as the optimum sample by degrading 96.1% of methylene blue from water. Moreover, the influence of pH of the solution, and contact time as decisive factors on the photo-degradation activity were investigated in this project. The optimum data for pH and time were found 9 and 60 min, respectively. The photo-degradation capacity of MnS2-SiO2-2 is improved (96.1%) due to the low band gap was found from UV-vis DRS. The antimicrobial data of MnS2-SiO2 were studied and demonstrated that the MnS2-SiO2 has fungicidal and bactericidal attributes.