RESUMEN
Silver nanoparticle is widely used in various field including medical, cosmetic, food and industrial purposes due to their unique properties in electrical conductivity, thermal, and biological activities. In the medical field, silver nanoparticles (AgNPs) have been reported to have strong antimicrobial and cytotoxic activities. This study aimed to synthesize and characterize silver nanoparticles (AgNPs) using Maclurodendron porteri (MP) extract and to evaluate the antimicrobial and cytotoxic activities of the synthesised MP-AgNPs. Green method of Ultrasound Assisted Extraction (UAE) was used to extract the leaves of M. porter. Liquid Chromatography -Mass Spectrometry/Quadrupole time-of-flight (LC-MS/QTOF) was used to identify the compounds in the leaf extract of M. porteri. Characterisation of the synthesised nanoparticles involved ultraviolet-visible (UV-Vis), Fourier Transform Infrared (FTIR), scanning electromagnetic microscopy (SEM), Zeta potential Analyzer and Particle Size Analyzer. The cytotoxic assay was conducted on MCF-7 and Caco-2 cell lines by MTT assay. Antimicrobial activity was tested on Gram-negative and Gram-positive bacteria using the disc diffusion method. Based on LC-MS/QTOF analysis, 430 compounds were found. The identified major compounds consist of amino acids, polyphenols, steroids, terpenoids and heterocyclic compounds which possibly act as reducing agents. 1 mM, 5 mM and 10 mM of silver nitrate solution were mixed with the leaf extract to form silver nanoparticles. 1.2 mg/ml of MP-AgNPs were found to have antibacterial activity against B. subtilis, S. aureus, E. coli, and P. aeruginosa with inhibitory zones of 8.0 ± 0.36 mm, 8.5 ± 0.45 mm, 7.5 ± 0.36 mm, and 9.0 ± 0.40 mm respectively. MP-AgNPs showed no cytotoxic activity against Caco-2 and MCF-7 cells. In conclusion, the presence of major amine compounds such as 10,11-dihydro-10,11-dihydroxyprotriptyline and harderoporphyrin in the extract facilitated the synthesis of AgNPs and the nanoparticle showed weak bioactivities in the assay conducted.
RESUMEN
BACKGROUND: Antibiotics are widely prescribed especially for upper respiratory tract infections (URTIs). Their irrational use can increase costs and resistance. AIM: Assess knowledge, attitude and prescribing of antibiotics for URTIs in Selangor, Malaysia, using a cross-sectional survey among general practitioners (GPs) working in private clinics in 2011. RESULTS: One hundred and thirty-nine physicians completed the questionnaire (response rate = 34.8%). 49.6% (n = 69) agreed antibiotics are helpful in treating URTIs, with most GPs agreeing antibiotics may reduce URTI duration and complications. The majority of GPs reported they felt patients expected antibiotics, with 36.7% (n = 51) agreeing patients would change doctors if they did not prescribe antibiotics and 21.6% (n = 30) agreeing when requested they prescribe antibiotics even if they believe them to be unnecessary. When assessed against six criteria, most GPs had a moderate level of knowledge of prescribing for URTIs. However, antibiotic prescriptions could be appreciably reduced. CONCLUSION: Further programs are needed to educate GPs and patients about antibiotics building on current initiatives.