Bio-medically active zinc oxide nanoparticles synthesized by using extremophilic actinobacterium, Streptomyces sp. (MA30) and its characterization

Figures & data

Figure 1. The role of actinobacterial metabolites as reducing agent in biosynthesis of ZnO nanostructures.

Figure 2. Phylogenetic tree of potent Streptomyces sp. (MA30) based on 16S rRNA sequence analyzed by Bootstrap method.

Figure 3. (A) FT-IR spectrum of the ZnO-NPs, (B) characterization of the ZnO-NPs by XRD analysis, and (C) EDX observation of ZnO-NPs.

Figure 4. Morphology of synthesized ZnO-NPs (A – SEM image, B – 2D and 3D topography images of AFM, C – HR-TEM image, D – SAED pattern, and E – DLS spectrum).

Table 1. Antibacterial activity of biosynthesized ZnO-NPs by agar well diffusion method. The results are presented as mean ± (SD) (n = 3).

		Zone of inhibition (diameter in millimeter)
S. no.	Test pathogens	ZnO-NPs (50 μg/mL)	Zinc acetate (50 μg/mL)
1	Staphylococcus aureus (NCIM 2079)	15.3 ± 0.58^e	7.3 ± 0.58^f
2	Bacillus subtilis (NCIM 2063)	16.3 ± 0.58^d	8.3 ± 0.58^e
3	Escherichia coli (NCIM 2256)	20.6 ± 0.58^b	10.0 ± 1.0^b
4	Klebsiella pneumoniae (NCIM 2706)	17.0 ± 0.0^c	8.6 ± 0.58^e
5	Enterobacter aerogenes (NCIM 5139)	17.3 ± 1.15^c	9.0 ± 0.0^d
6	Salmonella abony (NCIM 2257)	16.6 ± 0.58^d	9.6 ± 0.58^c
7	Proteus vulgaris (NCIM 2027)	22.6 ± 1.5^a	12.3 ± 0.58^a

Different superscript alphabets are used for representing the zone of inhibition from maximum to minimum. The activity of (+/-) 0.5 mm represent with same indication.

Figure 6. Antioxidant activity of actinobacterially synthesized ZnO-NPs. (A) DPPH radical scavenging activity and (B) nitric oxide free radical scavenging activity.

Figure 7. Cytotoxicity test of ZnO-NPs against MG63 (A, B) and Vero (C, D) cell lines at various concentrations.