Abstract:
The use of antimicrobial drugs has decreased the frequency of infectious ailments. But their
widespread use has generated drug-resistant microbes, so there is need to develop new rapid
acting antibiotics with less side effects. The silver nanoparticles have been recognized as
efficient broad spectrum antimicrobial agents. It uses mushroom glucans as reducing and
capping agent to decline its toxicity. The present study was primarily, on the nutritional,
biochemical and nutraceutical characterization of mushroom and ultimately, on the green
synthesis of silver nano-particles with mushroom glucans and then characterization,
antimicrobial and biochemical analysis through in vitro and in vivo studies. The four different
Pleurotus spps. including P1: Pleurotus ostreatus, P3: Pleurotus sajor-caju, P6: Pleurotus
sapidus and P8: Pleurotus columbinus were collected from mushroom culture bank of
Medicinal Mushroom Laboratory, Institute of Horticultural Sciences, University of
Agriculture, Faisalabad, Pakistan. Proximate analysis of the selected mushrooms depicted the
protein (19.07-30.15%), ash (2.1-9.14%), carbohydrate (65.66-82.47%) and fiber contents
(38.5-46.3%) were present in significant amounts whereas fats (1.04-6.01%) were in low
concentration. All the mushrooms showed potential total phenolic contents (TPC), total
flavonoid contents (TFC), DPPH radical scavenging and reducing properties. Selected
mushrooms showed DNA protection against H2O2, by use of calf thymus (ctDNA). A
moderate antimicrobial potential exhibited by all mushrooms against selected bacterial (E.
coli, P. multocida, B. subtilis and S. aureus) and fungal species (A. niger, A. flavus, F. solani
and H. maydis). Fatty acids profile by Gas chrometography-Mass spectroscopy (GC-MS)
showed that the unsaturated fatty acids were more prevalent over the saturated fatty acids
in targeted Pleurotus spps. Quantitative protein analysis depicted h i g h concentration of
proteins (33.47-45.78 mg/g) in selected Pleurotus spps. High performance liquid
chromatography (HPLC) analysis expressed variable concentration of sugars and organic
acids present in the Pleurotus spps. Quantitative ascorbic acid analysis depicted that they
were significantly higher (4.90-6.97 mg/g) in chosen Pleurotus spps. High performance
liquid chromatography (HPLC) analysis of α-tocopherols and β-carotenes showed that they
were present in targeted Pleurotus spps. Macro and micronutrients studies showed that all
four Pleurotus spps. have minerals [Na (19.09-39.2 mg/100g) and K (4.84-11.98 mg/100g)]
micronutrients [Ca (1.33-11 mg/100g), Mg (1.4-2.1 mg/100g) and P (2.1-4.3 mg/100g)] and
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trace elements [Cu (10.2-15.42 mg/100g), Mn (2.1-7.4 mg/100g), Zn (37.5-54.6 mg/100g)
and Fe (12.1-15.2 mg/100g)] while all were deficient of heavy metals like Pb. Green
synthesis of silver nano-particles performed by glucans from selected Pleurotus spps.
Extracted glucan and synthesized Glucan-AgNPs confirmed by Ultraviolet-Visible (UV-Vis)
spectra. Size of Glucan-AgNPs determined by Dynamic light scattering. The Glucans
characterized by Fourier transformation infrared spectroscopy (FT-IR), Scanning electron
microscopy (SEM) and X-ray diffraction (XRD) and Glucan-AgNPs were characterized by
FT-IR, Scanning electron microscopy-Energy dispersive spectroscopy (SEM-EDS),
Transmission electron microscopy (TEM) and XRD. In vitro studies showed that Glucan-
AgNPs revealed excellent antimicrobial, biofilm inhibition and anti-cytotoxic potentials. In
vivo studies performed on adult albino rats. The glucan-AgNPs significantly restored the
physical (Temperature), hematological (Total leukocyte count, neutrophil (%age) count and
ESR) and biochemical (C-reactive proteins) parameters elevated after induction of infection.
Histological examination revealed that there was no deposition of silver in small intestine,
skin, liver and kidney.