Eco-friendly synthesis of silver nanoparticles from the whole plant of Cleome viscosa and evaluation of their characterization, antibacterial, antioxidant and antidiabetic properties

Abstract

The current research is to develop an easy and eco-friendly method for the synthesis of three different concentrations of silver nanoparticles (1mMCvAgNPs, 2mMCvAgNPs and 3mMCvAgNPs) using aqueous whole plant extract of Cleome viscosa and to evaluate their antibacterial, antioxidant and antidiabetic properties. CvAgNPs were characterized by Using UV-vis spectrophotometer, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and transmission electron microscope (TEM). The formation of CvAgNPs was confirmed by the observation of band between 250 nm to 600 nm UV-vis spectrum. The crystalline structure of CvAgNPs with a face-centered cubic (FCC) was confirmed by XRD. The responsible phytochemicals for the reduction and capping material of CvAgNPs were observed with FT-IR. The SEM analysis confirmed the size and shapes of CvAgNPs. The CvAgNPs have shown the rich content of total phenolic and total flavonoid components. The CvAgNPs have shown significant antibacterial activity on multi drug resistance Gram-negative and Gram-positive bacteria and also have shown significant strong antioxidant activities (DPPH, ABTS, H₂O₂ scavenging, Phosphomolybdenum assay and reducing power). The inhibitory action of CvAgNPs on α-glucosidase and α-amylase was stronger than the inhibitory action of acarbose. To best of our knowledge, this is the first attempt on the synthesis of AgNPs using C. viscosa whole plant aqueous extract. The synthesized CvAgNPs exhibited good antimicrobial, antioxidant and antidiabetic properties. Hence, to validate our results, the in vivo studies at the molecular level are needed to develop Cleome viscosa as an antibacterial, antioxidant and anti-diabetic agent.

Keywords: Antibacterial; Antidiabetic; Antioxidant; Cleome viscosa; SEM; TEM; XRD.

Graphical abstract

Fig. 1

Schematic diagram of biosynthesis of CvAgNPs.

Fig. 2

UV–vis absorption spectrum of synthesized 1mMCvAgNPs, 2mMCvAgNPs and 3mMCvAgNPs.

Fig. 3

XRD spectra of (A) 1mMCvAgNPs, (B) 2mMCvAgNPs and (C) 3mMCvAgNPs.

Fig. 4

SEM images of synthesized (A) 1mMCvAgNPs (B) 2mMCvAgNPs and (C) 3mMCvAgNPs.

Fig. 5

EDX pattern of synthesized CvAgNPs.

Fig. 6

TEM micrograph. Size of (A) 1mMCvAgNPs, (B) 2mMCvAgNPs and (C) 3mMCvAgNPs with SAED pattern.

Fig. 7

FT-IR spectra of the synthesized (A) 1mMCvAgNPs (B) 2mMCvAgNPs and (C) 3mMCvAgNPs.

Fig. 8

TPC and TFC in the synthesized CvAgNPs. Each vertical bar represents the mean ± SE (n = 3). The vertical bars with similar colour and having the same alphabet do not differ significantly whereas the bars with similar colour and having the different alphabet differ significantly at p < 0.05. (One Way ANOVA followed by Tukey’s post hoc test).

Fig. 9

Zone of inhibition of synthesised CvAgNPs against K. pneumoniae, S. aureus, P. aeruginosa, E. coli and P. putida. Data are representing mean ± SE (n = 3).

Fig. 10

Bactericidal activity of synthesized 1mMCvAgNPs, 2mMCvAgNPs, 3mMCvAgNPs and gentamycin against (A). K. pneumoniae, (B). S. aureus, (C). P. aeruginosa, (D). E. coli and (E). P. putida. NC– Negative control (Distilled Water); PC-Positive control (Gentamycin).

Fig. 11

Percentage of DPPH, ABTS, H₂O₂ radical scavenging activity and total antioxidant capacity (TAC) of the biosynthesized CvAgNPs.

Fig. 12

IC₅₀ values of DPPH, ABTS, H₂O₂ scavenging activity and total antioxidant activity of synthesized CvAgNPs. Each vertical bar represents the mean ± SE (n = 3). The vertical bars with similar colour and having the same alphabet do not differ significantly whereas the bars with similar colour and having the different alphabet differ significantly at p < 0.05. (One Way ANOVA followed by Tukey’s post hoc test).

Fig. 13

Ferric reducing antioxidant power capacity of biosynthesized CvAgNPs.

Fig. 14

Inhibition activity of CvAgNPs on α-amylase, α-glucosidase and HbA1c.

Fig. 15

IC₅₀ values of α- amylase, α-glucosidase and HbA1c inhibitory activity of synthesized CvAgNPs. Each vertical bar represents the mean ± SE (n = 3). The vertical bars with similar colour and having the same alphabet do not differ significantly whereas the bars with similar colour and having the different alphabet differ significantly at p < 0.05. (One Way ANOVA followed by Tukey’s post hoc test).