Chitosan-coated liposomes of Carissa spinarum extract: synthesis, analysis and antipneumococcal potency

In the present study, a chitosan-coatedCarissa spinarum-polyphenol-loaded liposome (LipCsP-chitosan) nanocarrierwas fabricated for the delivery ofC. spinarumpolyphenols (CsPs) to improve the bioavailability andantipneumococcal potential of CsPs againstKlebsiella pneumoniae. LipCsP-chitosan was synthesized using the iongelation method and characterized by using a Malvern Zetasizer and Fourier transform infrared (FTIR) spectroscopy.CsP encapsulation and release kinetics were investigated. The antipneumococcal activity of the nanoformulationswas assessed using agar-well diffusion and microdilution assays. LipCsP-chitosan exhibited a hydrodynamic size anda zeta potential of 365.22 ± 0.70 nm and +39.30 ± 0.61 mV, respectively. The encapsulation efficiency of LipCsP-chitosan was 81.5%. FTIR analysis revealed interactions of the liposomes with chitosan and CsPs. A biphasic CsPrelease profile followed by a sustained-release pattern was observed. LipCsP-chitosan presented a higherbioaccessibility of polyphenols in the simulated gastric phase (74.1 ± 1.3%) than in the simulated intestinal phase(63.32 ± 1.00%). LipCsP-chitosan had a relative inhibition zone diameter of 84.33 ± 2.51% when compared with CsPs.At a minimum inhibitory concentration of 31.25 mg/ml, LipCsP-chitosan reduced the viability ofK. pneumoniaeby57.45 ± 3.76% after 24 h. The results obtained from this study offer a new approach to the utilization of LipCsP-chitosan as nanocarriers for candidate antipneumococcal agents

有機反応における炭素－酸素結合の形成と切断に関する研究

長崎大学学位論文 [学位記番号]博（医歯薬）甲第546号 [学位授与年月日]平成24年9月20

In-vitro Antimicrobial Properties of Methanol extracts of three Medicinal Plants from Kilifi District - Kenya

Multidrug resistant microbes are a health management challenge in immunocopromised individuals. The study aimed to evaluate antimicrobial potential and toxicity of the methanol extracts of Hosludia opposita, Rhus natalensis and Combretum illairii. The plants were collected from Kilifi District and authenticated at East African Herbarium. Samples collected were extracted in methanol. Quantitative bioassay was done using disc diffusion method; minimum inhibition concentration was done using broth dilution methods. The isolates used for bioactivity testing were Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans and Trichophyton mentarophyte. Phytochemical screening was done using thin layer chromatograpy and cell toxicity was done using human embryonic lung cells. The H. opposita and C. illairii had terpenoids, flavonoids and anthaquinones. All the extracts were safe to the mammalian cells. Combretum illairii plant extracts had good activity against S. aureus and P. aeruginosa with inhibition zones diameters of 15.60 mm and 17.00 mm respectively. Rhus natalensis had an MIC of 6.25mg/ against both S. aureus and P. aeruginosa. The plant extracts were active against both bacteria and fungi. The result indicates that’s the plants extracts have potential for managing infections caused by the tested microbes. Isolation of compounds present and determination of their bioactivity should be done together with conservation initiatives

Concise Synthesis of Photocleavable Molecular Tag for Laser Desorption Ionization Mass Spectrometry via Fries Reaction

A new synthetic route for the photocleavable molecular tag for laser desorption ionization mass spectrometry (LDI-MS) was achieved using Fries reaction of 2,6-dimethylphenyl ester as its key reaction. Zirconium chloride was found as uniquely efficient adjuvant to promote the reaction. The molecular tag was obtained in 5 steps without chromatographic purification

Inorganic Nanocarriers: Surface Functionalization, Delivery Utility for Natural Therapeutics - A Review

This research article was published by Scientific.Net, 2022Inorganic nanocarriers for a decade have increased interest in nanotechnology research platform as versatile drug delivery materials. The utility of the inorganic nanocarriers for delivery of therapeutic agents is attributed to their unique properties such as magnetic, photocatalytic nature and the ability to exhibit surface functionalization. Herein, we review the surface functionalization and delivery utility for natural therapeutics exhibited by inorganic nanocarriers mostly focusing on their magnetic, photocatalytic and the plasmonic properties. The review also highlights the influence of electronic property of inorganic surface on functionalization of ligand based natural therapeutic agents. Improvement of stability and therapeutic potential by formation of nanocomposites are detailed. Furthermore, we suggest improvement strategies for stability and toxicity reduction of inorganic nanoparticles that would potentially make them useful for clinical application as therapeutic delivery tools for treatment of various diseases

Development and Characterization of Nanovesicles Containing Phenolic Compounds of Carissa spinarum: Encapsulation, Release Kinetics, Antimicrobial Activity and Mathematical Modeling

This research article was published by Trans Tech Publications Ltd in 2023The aim of this study was to develop and characterize a delivery system for polyphenols from an extract of Carissa spinarum leaves, based on liposomes. Liposomes loaded with Carissa spinarum polyphenols (nanoliposomal CsP) were prepared by ethanol-solvent injection method and characterized in terms of zeta potential, size, and polydipersity index by using Zeta sizer and Fourier Transform Infrared spectrum analysis. Total Phenolic content was measured by using Folin-Ciocalteu method and entrapment efficiency was evaluated. The release behavior was conducted in Phosphate Buffer Saline (PBS) solution at pH, 7.4 and Kinetic model fitted to evaluate mechanism of release. Disc diffusion sensitivity test was used to evaluate antimicrobial activity of free extract and nanoliposomal CsP. The mean diameter of nanoliposomal CsP was 181 ± 1.02 nm and had 0.345 ± 0.014 polydipersity index. Zeta potential value for nanoliposomal CsP was-45.6 ± 8.84 mV. Entrapment efficiency under the optimum conditions was 66.11 ± 1.11%. and the nanoliposomal CsP was stable over 30 days. The antibacterial activity of nanoliposomal CsP exhibited inhibition zone diameter of 14.33 ± 1.53 mm and 12.00 ± 1.23 mm against S. aureus and E. coli respectively The results reveal the Carrisa spinarum liposome can be applied as potential carrier for delivery of polyphenols to improves therapeutic action against bacterial strain

Antimalarial activity and toxicity evaluation of Kenyan Hugonia castaneifolia Engl. Teclea nobilis Del. and Turraea mombassana C.DC

The aqueous and methanol extracts of three medicinal plants, Hugonia castaneifolia, Teclea nobilis and Turrae mombassana were evaluated for in vitro antiplasmodial activity against a chloroquine sensitive Plasmodium falciparum strain (D6) and in vivo, against a P. berghei ANKA strain in mice. The extracts were also assessed for cytotoxicity in Vero cell lines and acute toxicity in mice. The water extracts were moderately active with IC50 of 33.07 3g/ml for T. mombassana and 23.92 3g/ml for H. castaneifolia while the methanol extracts of T. mombassana, H. castaneifolia and T. nobilis were highly active in vitro with IC50 of 6.1 3g/ml, 8.86 3g/ml and 8.61 3g/ml respectively. The methanol extract of T. mombassana had the highest chemosupppression followed by the methanol extract of H. castaneifolia in vivo. Aqueous extract of H. casteinofolia was weakly cytotoxic against Vero cells CC50 =22.00 3g/ml. No toxic effect or mortality was observed in mice treated orally with any of the extracts at the highest concentration of 5000mg/kg. These results demonstrate antimalarial potential and safety of the three medicinal plants tested, which are used traditionally for the treatment of malaria in Kenya. Keywords: Antiplasmodial; Malaria; Toxicity; Meliaceae; Rutaceae; Linacea

Chitosan-coated liposomes of Carrisa spinarum extract: synthesis, analysis and anti-pneumococcal potency

This research article was published by ICE Publishing, 2023In the present study, a chitosan (CS)-coated liposome (LipCsP-Chitosan) nanocarrier was fabricated for the delivery of Carissa spinarum (CsP) polyphenols to improve bioavailability and anti-pneumococcal potential against Klebsiella pneumoniae. LipCsP-Chitosan was synthesized by the ion gelation method and characterized by using a Malvern zetasizer and Fourier Transform Infrared (FTIR); CsP encapsulation and release kinetics were investigated. Anti-pneumococcal activity of the nanoformulations was accessed by agar-well diffusion and microdilution assays. LipCsP-chitosan exhibited a hydrodynamic size and zeta potential of 365.22 ± 0.70 nm and +39.30 ± 0.61 mV, respectively. CsP had an encapsulation efficiency of 81.5%. FTIR analysis revealed the interaction of the liposomes with chitosan and the CsP. A biphasic CsP release profile followed by a sustained release pattern was observed. LiPCsP-Chitosan presented a higher bioaccessibility of polyphenols in the simulated gastric phase (74.1% ± 1.3) than in the simulated intestinal phase (63.32% ± 1.00). LipCsP-chitosan had a relative inhibition zone diameter of 84.33% ± 2.51 when compared to CsP. At minimum inhibition concentration of 31.25 mg/mL, LipCsP-Chitosan reduced the viability of Klebsiella pneumoniae by 57.45% ± 3.76 after 24 h. The results obtained from the current study offer a new approach to the utilization of LipCsP-Chitosan as nanocarriers for candidate anti-pneumococcal agents

In vitro antiproliferative potential of Annona senegalensis Pers. and Allophylus africanus P Beauv. plant extracts against selected cancer cell lines

This research article published by Journal of Medicinal Plants Research, Vol. 13(13), 10 July, 2019The medicinal plants Annona senegalensis Pers. and Allophylus africanus P Beauv. are used in Tanzania traditional medicine for the treatment of cancer. However, there is no scientific documentation on their therapeutic effectiveness. The present study evaluated antiproliferative potential as an indicator of anticancer activity of A. senegalensis and A. africanus plant species from Tanzania. A. senegalensis and A. africanus were collected from Ugweno village at Kilimanjaro, Tanzania. Different types of extracts were prepared in dichloromethane/methanol (DCM:MeOH), petroleum ether, DCM, ethyl acetate (EtOAc), MeOH and water respectively. Antiproliferative activity against HCC 1396 (breast), HEp-2 (throat) and CT 26 (colon) cancer cell lines was assessed by the MTT cell viability assay. The results of the present study showed that the antiproliferative activity varied between plant extracts and the cancer cell lines. The highest antiproliferative activity was achieved with petroleum ether extract of A. senegalensis against HEp-2 with an IC50 value of 0.42 ± 0.09 μg/ml. This also depicted the highest selectivity to cancerous cells (SI value 94.19) compared to the other extracts. A. africanus also depicted good antiproliferative activity against HEp-2 with IC50 values of 1.00 ± 0.41 and 2.37 ± 1.45 μg/ml for DCM:MeOH and petroleum ether extracts, respectively. The findings validate the traditional use of A. senegalensis and A. africanus in the treatment of cancer. Results also support previous studies which demonstrated the effect of extraction solvent used in extraction of bioactive agents from medicinal plants. Further studies involving the isolation of pure antiproliferative compounds against cancer cells from the two plants are recommended to elucidate bioactive molecules