55 research outputs found
Biosynthesis, Characterization and Antimicrobial Activity of Silver Nanoparticles Using Cell Free Lysate of Bacillus Subtilis: A Biotechnology Approach
Present study was aimed at the bio-synthesis and characterization of silver nanoparticles (AgNPs) using bacterial cell free lysate of Bacillus specie isolated from iron-rust contaminated soil sample from the Niger Delta region of Nigeria. This method was cost effective, eco-friendly and an alternative to chemical synthesis which is hazardous and requiring tedious synthetic manipulation. This study also evaluated the antimicrobial effect of the synthesized silver nanoparticles. Silver nanoparticles produced by reacting cell-free lysate of Bacillus subtilis and 1 mM of aqueous silver nitrate solution were characterized by Ultraviolet-visible spectroscopy, Transmission electron microscopy (TEM) and Photon correlation microscopy (Zeta sizer). The UV-Visible spectrophotometric result revealed an absorption maxima corresponding to peaks near 428 nm, depicting reduction of ionic silver (Ag+) to silver atom (Ag0). It has already been reported that nitrate reductase enzymes are implicated in metal ion reduction reactions. The Transmission electron microscopy analysis revealed that the AgNPs size ranged between 58.24 ± 1.04 nm and 72.20 ± 2.10 nm complementing the result obtained from Photon correlation microscopy (76.86 ± 1.14 nm). The antibacterial activity of AgNPs gave highest inhibition zone diameter of 26 mm on Pseudomonas aeruginosa at the dose of 0.10 mg/ml and 14 mm on tested Candida albicans. The synthesized silver nanoparticles were found to produce a dose dependent antimicrobial inhibitory effect while surface adsorption and lysis were implicated as the mode of action
Rapid Synthesis of Thiol-Co-Capped-CdTe/CdSe/ZnSe Core Shell-Shell Nanoparticles
CdTe QDs has been demonstrated in many studies to possess good outstanding optical and photo-physical properties. However, it has been established from literature that the toxic Cd2+ that tends to leak out into nearby solutions can be protected by less toxic ZnS or ZnSe shells leading to the synthesis of core-shells and multi-core-shells. Hence, this has allowed the synthesis of CdTe multi-core-shells to have gained much interest. The preparation of most CdTe multi-core-shells reported from various studies usually has a longer reaction time (6–24 h) in reaching their highest emission maxima. The synthesis of CdTe multi-core-shells in this study only took 35 min to obtain a highest emission maximum compared to what has been reported from the literature. CdTe multi-core-shells were synthesized by injecting 7, 14, and 21 mL each of Zn complex solution and Se ions into the reacting mixture containing CdTe core-shells (3 h) at 5 min intervals over a 35 min reaction time. The emission maxima of the MPA-TGA-CdTe multi-core-shells at 21 mL injection was recorded around 625 nm. Therefore, we are reporting the rapid synthesis of five different thiol co-capped CdTe/CdSe/ZnSe multi-core-shell QDs with the highest emission maxima obtained at 35 min reaction time
Beneficial effects of medicinal plants in fish diseases
Fish are constantly in contact with pathogens inhabiting water. High populationdensity as well as poor hydrodynamic conditions and feeding lead to an increased sensitivitytowards infections. In order to prevent major economic losses due to diseases, variousmedications are used for treatment and prevention of infections. The use of antimicrobialdrugs in aquacultures could lead to emergence of resistance in pathogenic microorganisms.Alternatives are being sought over the last few years to replace antibiotics, and medicinalplants are one of available options for this purpose. These plants are rich in secondarymetabolites and phytochemical compounds, which have an effect against viral, bacterial, andparasitic diseases in fish. Their main advantage is their natural origin and most of these plantsdo not represent threat for human health, the fish, and the environment. The goal of this reviewis to present information on the treatment of viral, bacterial, and parasitic diseases in fishthrough medicinal plants, with focus on the mechanisms of action of the identified secondarymetabolites, fractions, or plant extracts
Nano-enabled liposomal mucoadhesive films for enhanced efavirenz buccal drug delivery
Buccal films (BFs) were prepared using a solvent casting method using the liposomal suspension as the dispersing medium. Optimization of some physical properties of the films containing different amounts of polymers was done using digital Vernier calliper and digital weighing balance. The physiochemical properties of the best optimized properties were characterized using Differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM), Energy dispersive X-ray spectroscopy (EDS), and Scanning Electron Microscopy (SEM). Permeation study of the BFs composed of Carbopol (CP) alone and CP to Pluronic 127 (PF127) demonstrated better bio-adhesive properties than the films made of other polymers such as HPMC (hydroxyl propyl methyl cellulose) and HPMC-PF127. These CP based BFs (without and with PF127) exhibited good film thickness 0.88 ± 0.10 and 0.76 ± 0.14 mm, with weight uniformity 68.22 ± 1.04 and 86.28 ± 2.16 mg, satisfactory flexibility values 258 and 321, and slightly acidic pH 6.43 ± 0.76 and 6.32 ± 0.01. The swelling percentage was found to be 50% for CP and 78% for CP-PF127. The cumulative amount of drug that permeated through the buccal epithelium after 24 h was about 66% from CP and 75% from CP-PF127
Nano-enabled liposomal mucoadhesive films for enhanced efavirenz buccal drug delivery
Buccal films (BFs) were prepared using a solvent casting method using the liposomal suspension as the dispersing medium. Optimization of some physical properties of the films containing different amounts of polymers was done using digital Vernier calliper and digital weighing balance. The physiochemical properties of the best optimized properties were characterized using Differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM), Energy dispersive X-ray spectroscopy (EDS), and Scanning Electron Microscopy (SEM). Permeation study of the BFs composed of Carbopol (CP) alone and CP to Pluronic 127 (PF127) demonstrated better bio-adhesive properties than the films made of other polymers such as HPMC (hydroxyl propyl methyl cellulose) and HPMC-PF127. These CP based BFs (without and with PF127) exhibited good film thickness 0.88 ± 0.10 and 0.76 ± 0.14 mm, with weight uniformity 68.22 ± 1.04 and 86.28 ± 2.16 mg, satisfactory flexibility values 258 and 321, and slightly acidic pH 6.43 ± 0.76 and 6.32 ± 0.01. The swelling percentage was found to be 50% for CP and 78% for CP-PF127. The cumulative amount of drug that permeated through the buccal epithelium after 24 h was about 66% from CP and 75% from CP-PF127
Phytochemical, anti-inflammatory and anti-trypanosomal properties of Anthocleista vogelii Planch (Loganiaceae) stem bark
Ethnopharmacological relevance: Anthocleista vogelii Planch (Loganiaceae) is used in African Traditional Medicine for the treatment of pain and inflammatory disorders as well as sleeping sickness. Aim of the study: To determine the in vivo anti-inflammatory and in vitro anti-trypanosomal activities of the extracts of A. vogelii stem bark and identify the phytochemical classes of the fractions responsible for the activities. Materials and methods: The in vivo anti-inflammatory activity of the extracts was evaluated using the egg albumin-induced rat paw oedema model while the in vitro anti-trypanosomal activity was assessed on Trypanosoma brucei brucei. The in vitro cytotoxicity was assessed on HeLa (human cervix adenocarcinoma) cell line. Results: The methanolic extract of A. vogelii stem bark, with 11.2% yield, gave LD50 > 5000 mg/kg. The n-hexane fraction of the extract contains steroids, terpenes and fatty acids and yielded non-cytotoxic terpenoidal column fraction with anti-trypanosomal IC50 of 3.0 μg/mL. The ethylacetate fraction at 100 mg/kg dose significantly (p less than 0.05) provoked 37.8, 62.5 and 69.7% inhibition of oedema induced by egg-albumin at the second, fourth and sixth hours respectively. Conclusion: The study demonstrated that the anti-inflammatory and anti-trypanosomal activities of A. vogelii are probably due to non-cytotoxic terpenoids and validated the traditional use of A. vogelii in the treatment of inflammation and sleeping sickness
Green synthesis of zinc oxide nanoparticles using Solanum torvum (L) leaf extract and evaluation of the toxicological profile of the ZnO nanoparticles–hydrogel composite in Wistar albino rats
Current study reports a simple and one-pot synthesis of zinc oxide nanoparticles (ZnONPs) using an aqueous extract of Solanum torvum and evaluation of its toxicological profile (0.5% w/w and 1.0% w/w) in Wistar albino rats with respect to the biochemical index. The nanoparticles were characterized using ultraviolet–visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction technique. Dynamic light scattering (DLS) and zeta potential of synthesized nanoparticles were analyzed to know the average size and stability of particles. Synthesized nanoparticles were stable, discreet, and mostly spherical, and size of particles was within the nanometre range. Biochemical markers of hepatic and renal functions were measured. Zinc oxide nanoparticles significantly decreased serum uric acid level (p  less than  0.001) in a dose-dependent manner, while the serum alkaline phosphatase level was increased at the two test doses. The level of alanine transaminase was increased after exposure for 28 days (p  less than  0.05). This study concludes that biogenic zinc oxide nanoparticles-infused hydrogel applied dermatologically could affect hepatic and renal performance in rats, and there was an observed cumulative toxicological effect with time of exposure
Anti-cancer and anti-trypanosomal properties of alkaloids from the root bark of Zanthoxylum leprieurii Guill and Perr
Purpose: To isolate the anti-cancer and anti-trypanosomal principles of Zanthoxylum leprieurii, a medicinally versatile wild tropical plant used for managing tumours, African trypanosomiasis, and inflammation in southeastern Nigeria. Methods: The pure compounds were isolated using chromatographic methods. The structural elucidation of the pure compounds was based on their NMR (1D and 2D) and mass spectral data as well as chemical test results. Structure-activity relationships were based on the structural differences among the compounds. The cytotoxicity of the extracts and compounds (1, 2, 3, and 4) was evaluated in HeLa (human cervix adenocarcinoma) cell line while the trypanocidal activities were evaluated on Trypanosoma brucei brucei. Results: Two acridone alkaloids, 1-hydroxy-3-methoxy-10-methylacridin-9 (10H)-one, named fabiocinine (1), and 1-hydroxy-2,3-dimethoxy-10-methylacridin-9 (10H)-one (arborinine, 2), together with a furoquinoline alkaloid, skimmianine (3), and a chelerythrine derivative, 6-acetonyl-5,6-dihydrochelerythrine (4) were isolated from the root bark of Zanthoxylum leprieurii. Skimmianine (3) exhibited cytotoxicity and anti-trypanosomal IC50 of 12.8 and 13.2 µg/mL respectively (p less than 0.05). Compound (1) and arborinine (2) were selectively cytotoxic to HeLa cells with cytotoxicity IC50 of 28.49 and 62.71 µg/mL, respectively, while (4) did not show significant activity (p less than 0.05). Conclusion: Zanthoxylum leprieurii root bark contains cytotoxic and trypanocidal compounds, and is thus a potential source of anti-cancer and anti-trypanosomal leads
Antibacterial effects of Alchornea cordifolia (Schumach. and Thonn.) Müll. Arg extracts and compounds on gastrointestinal, skin, respiratory and urinary tract pathogens
Ethnopharmacological relevance:The leaves, stems and roots ofAlchornea cordifolia(Schumach. andThonn.) Müll. Arg. are used as traditional medicine in many African countries for the management ofgastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds.Aim of the study:To determine the in vitro antibacterial activity of the crude extracts of leaves and stemsofA. cordifoliaon gastrointestinal, skin, respiratory and urinary tract pathogens and to identify thecompounds in the extracts that may be responsible for this activity.Materials and methods:The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethylacetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolatedfrom these extracts were evaluated by means of the micro-dilution assay against four Gram-positivebacteria, i.e.Bacillus cereusATCC 11778,Enterococcus faecalisATCC 29212, Staphylococcus aureusATCC25923 andS. saprophyticusATCC 15305,as well as four Gram-negative bacterial strains, i.e.EscherichiacoliATCC 25922, Klebsiella pneumoniaeATCC 13883, Moraxella catarrhalisATCC 23246 andProteus mir-abilisATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays inconjunction with chromatographic techniques. The identification and characterisation of the isolatedcompounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry(FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses.Results:The leaves and stems ofA. cordifoliaexhibited varied antibacterial activity against all eight pa-thogens. Most of the MIC values ranged between 63 and 2000mg/ml. The highest activities for the crudeextracts (63mg/ml) were observed againstS. saprophyticus[stem (EtOAc, CHCl3and hexane), leaves(MeOH, EtOH, EtOAc and CHCl3)],E. coli[stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc andCHCl3)],M. catarrhalis[leaves (EtOAc and CHCl3)],K. pneumoniae[stem (CHCl3), leaves (CHCl3)] andS.aureus[leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3),friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these com-pounds displayed some antibacterial activity against the eight pathogens with highest activity againstS.saprophyticus(2mg/ml). Furthermore, this is thefirst report of compounds1,2,3,4,6and7isolated fromA. cordifoliaand where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented.Conclusion:The study demonstrated that the antibacterial activities ofA. cordifoliaextracts may be dueto the presence of the seven isolated compounds, where compounds3–6showed the best activity. Theobserved activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports thetraditional use for the treatment of such ailments
Preparation and characterization of isoniazid-loaded crude soybean lecithin liposomes
Unexpected substituent-dependent regioselectivty challenges in the synthesis of C-benzylated (N-arylcarbamoyl)phosphonate esters have been resolved. The C-benzylated N-furfurylcarbamoyl derivative showed low micromolar PfLDH inhibition, while one of the C-benzylated N-arylcarbamoyl analogues was active against Nagana Trypanosoma brucei parasites which are responsible for African trypanosomiasis in cattle
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