Metrics details Abstract The current work investigated the green and low-cost preparation of silver nanoparticles AgNPs using the aqueous extract from Launaea taraxacifolia leaf and studied its antimicrobial effects. The leaf extract was analysed in a gas chromatogram—mass spectrometer to assess the phytochemicals present. UV—Vis spectrophotometer was used to monitor the formation of AgNPs, the morphological assessment was performed by a scanning electron microscope, energy dispersive X-ray analysis was used to determine the elemental composition, the particle size and shape were studied using transmission electron microscopy, and the vibrational modes of bonds in the AgNPs were assessed by Fourier transformed infrared spectroscopy. The AgNPs produced were spherical and in a size range of 9—
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Metrics details Abstract The current work investigated the green and low-cost preparation of silver nanoparticles AgNPs using the aqueous extract from Launaea taraxacifolia leaf and studied its antimicrobial effects. The leaf extract was analysed in a gas chromatogram—mass spectrometer to assess the phytochemicals present.
UV—Vis spectrophotometer was used to monitor the formation of AgNPs, the morphological assessment was performed by a scanning electron microscope, energy dispersive X-ray analysis was used to determine the elemental composition, the particle size and shape were studied using transmission electron microscopy, and the vibrational modes of bonds in the AgNPs were assessed by Fourier transformed infrared spectroscopy.
The AgNPs produced were spherical and in a size range of 9— Against P. Therefore, the AgNPs prepared using L. Graphic Abstract Introduction Nanotechnology has great potential in the field of materials science for producing materials of various types at nanoscale level. In this dimension, nanomaterials can generate therapeutic activities and several other unique properties [ 1 ] compared with their corresponding bulk materials. This is because their physicochemical properties, like surface charge, surface area, size, and shape greatly influence their properties.
At the nanometre scale, silver has applications in various fields, including medicine, biosensors, and analysis. AgNPs have long been credited with strong inhibitory effects against bacteria and fungi found in medical and industrial processes [ 3 , 4 ].
Thus, AgNPs have been applied in topical ointments to stop burns and open wounds from being infected [ 5 ]. Besides, biologically synthesized AgNPs are highly toxic to several multi-drug resistant human pathogens, and in monodisperse morphology, they are more effective in drug delivery, resonance imaging, and medical diagnostics [ 6 ].
There are many chemical techniques of synthesizing AgNPs, some involve reducing silver ions chemically in aqueous solutions, which could employ stabilizing agents. Others are decomposing silver ion thermally in organic solvents, chemical reduction and carrying out photoreduction in reverse micelles [ 7 , 8 ], and using radiation chemical reduction method [ 9 ].
However, most of these techniques are complex and involve the use of very expensive equipment [ 10 ]. Furthermore, these processes may release harmful gases into the atmosphere and the chemicals used may be hazardous and dangerous to health and pollute the environment as well [ 10 ].
The plant extract alternative pathway for synthesizing AgNPs, apart from its eco-friendliness, has the advantages of being facile and cost effective [ 11 , 12 ]. Additionally, in plant-mediated synthesis, the phytochemicals inherent in the plants, after playing a reducing role, also act as capping agents towards forming the nanoparticles.
Based on this, the AgNPs obtained from this technique are safe for human medical use [ 12 , 13 ]. It owes its origin to the family Asteraceae Compositae and is commonly found in several African countries including Ghana, Senegal, Benin, and Nigeria. There is a report that the milky fluid which exudes from the plant possesses therapeutic effect against conjunctivitis, and at a specific dosage, the leaves have been shown to provide protection against gentamicin-induced kidney damage in rats [ 14 ].
It is against this backdrop that the current work is designed to synthesize AgNPs from L. Based on our investigation, there is currently no report in literature on the preparation of silver AgNPs from L. Experimental Materials The L.
AgNO3 was purchased from Sigma-Aldrich. Preparation of L. Then, the powder 4. After allowing to cool to room temperature, the mixture was filtered to obtain the L. Synthesis of AgNPs The synthesis was performed by modifying a previous method by Krishnamoorthy and Jayalakshmi [ 18 ]. The reaction was performed in a dark room at room temperature and left overnight to minimize photoactivation of the AgNO3.
The particles formed were washed in deionized water to remove any residual organic compounds still present in the AgNPs. Characterization techniques A gas chromatograph—mass spectrometer GC—MS Shimadzu, QPSE performing at a injection ratio was used to determine the phytochemicals present in the ethanolic solution of the L.
The phytochemicals were identified using a software having a database incorporated into the GC—MS machine. Taraxacifolia leaf extract and AgNO3. The UV—visible spectrum of the L. Taraxacifolia leaf extract was also obtained at a similar wavelength range. The average particle size and distribution were determined from the TEM micrograph using a software—ImageJ.
The type of bonds present in the L. Antimicrobial analysis Broth dilution method as described by Krishnan et al. Bacterial suspensions of the test strains were prepared using a 0. Negative and positive control tubes were also prepared to check the sterility of the procedure and the bacterial activity, respectively.
The negative control tube contained only sterile broth, while the positive control tube contained the broth and bacterial inoculum, but no antimicrobial agent. The lowest concentrations of the AgNPs that visually inhibited the growth of the test microorganisms were taken as the MICs. Thereafter, the agar plates were observed for the presence or absence of bacterial growth. The plate representing the lowest concentration of the AgNPs which did not exhibit any bacterial growth or colony was taken as the MBC.
MBC is defined as the lowest concentration of antimicrobial agent that kills Results and discussion UV—Vis spectrophotometry During the biosynthesis reaction, colour change occurred as the solution changed colour from buff to brown as a result surface plasmon resonance SPR phenomenon caused by the formation of the AgNPs [ 20 ]. The absence of additional absorption bands at higher wavelengths indicates spherical shape uniformity of the nanoparticles [ 24 ].
The UV—Vis spectrum recorded and the visual observation made indicated that a bio-reduction reaction occurred giving rise to the formation of AgNPs. The result indicated that most of the biomolecules are alcohols, amides and carbohydrates.
Amides, in particular, have been shown to act as reducing and capping agents to obtain AgNPs [ 27 , 28 ].
LAUNAEA TARAXACIFOLIA PDF
Published05 Dec Abstract Launaea taraxacifolia and Amaranthus viridis used by people of Western Africa in the treatment of malaria and related symptoms were assessed for their antiplasmodial value against the chloroquine sensitive strain of Plasmodium berghei. The percentage of parasitemia, survival time, and haematological parameters were determined. Both extracts significantly inhibited parasitemia and improved survival time in infected mice. The crude extracts prevented loss of some haematological parameters.
Dakinos Evidence-Based Complementary and Alternative Medicine Therefore, in vitro propagation protocol for this crop is being investigated. The number of launaez branches on maturity 80 DAP ranges from nine to ten per plant. Increased lipid peroxidation and decreased activities of superoxide dismutase, glutathione, and catalase were also observed in cisplatin-exposed groups. Micronuclei are markers that provide information about the integrity of chromosome structure during nuclear division. Plants in the shade did not flower at all. Research over the years has revealed that Launaea taraxacifolia possesses important pharmacological activities. Launaea taraxacifolia Willd.