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Pest outbreaks are among the major factors that affect agroecosystems, subsequently leading to the excessive use of fertilizers and toxic pesticides, polluting the environment and causing serious health concerns. This indiscriminate use of conventional pest-controlling chemicals has led to the development of pesticide resistance, affecting soil fertility. Ultimately, there is a need to find alternative means to manage pest situations. In this regard, nanotechnology has emerged as a novel technique with a wide range of applications in agrochemical and Phyto-protection systems to control pests to a significant extent. Nanoparticles are being used in different nanoformulations of pesticides, insecticides, and nanobiopesticides with broad-spectrum biopesticidal potential, which could be fabricated by using various metals like silver, zinc, alumina, copper, gold, and titanium. However, further research is required to understand the interaction between the metals and the natural biopolymers needed for their reduction during nanoparticle formulation. Keeping in view the importance of the issue, the current review encompasses a detailed discussion of pest-related issues including crop losses and their global impact followed by the mechanism of pesticide resistance and demand for biopesticides. Furthermore, the role of nanobiopesticides in pest control has been highlighted briefly with their mode of action. [ABSTRACT FROM AUTHOR]

This current study is designed to incorporate sericin protein as a reducing, capping, and stabilizing agent to synthesize sonication‐mediated silver nanoparticles. Fabrication of sericin‐reduced silver nanoparticles (Sr‐AgNPs) is confirmed using UV–visible spectrophotometry, zeta sizer, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X‐Ray diffraction (XRD), and thermogravimetric analysis (TGA). UV–Vis spectral peak of Sr‐AgNPs is observed at 420–440nm while the average size is found between 3 to 30 nm. SEM also confirms the reduction of large‐sized (1–40 µm) sericin macromolecules into nanometric hexagonal and triangular silver nanoparticles with a normal distribution (polydispersity index > 0.5). FTIR peaks from 500 to 4000cm−1 are analyzed for sericin while Sr‐AgNPs peaks with minor shifts (700–1000 cm−1 (COOCO stretching) in Sr‐AgNPs) are also observed. XRD peaks of 2θ at 27° with multiple low peaks at 38.2°, 47°, 49°, and 63.8° authenticate the amorphous nature of sericin and sharp peaks at 36°, 48°, 54.3°, and 61.9° with miller indices (hkl) of 98, 111, 200, and 211, assess the crystalline structure of Sr‐AgNPs. TGA reveals that sericin enhances the stability of silver NPs at high temperature (200–600 °C) by lowering the percentage weight loss from 70–80% to 60–65%. [ABSTRACT FROM AUTHOR]

Present study was aimed to assess the bactericidal potential of sericin‐capped silver nanoparticles (Se‐AgNPs) synthesized by heat, light, and sonication. Se‐AgNPs were characterized by size analyzer, UV spectrophotometry, energy‐dispersive X‐ray spectroscopy, and Fourier transform infrared spectroscopy. Average size of Se‐AgNPs synthesized by heat, light and sonication was 53.60, 78.12, and 7.49 nm, respectively. All (10) bacterial strains were exposed to Se‐AgNPs prepared from different methods to compare their antibacterial potentials. Largest zone of inhibition (13 ± 1.15 mm) was observed for sonication‐based nanoparticles (NPs) against Klebseilla pneumoniae while the smallest zone of light assisted NPs against Serratia rubidaea (5 ± 1 mm). Bacterial strains were also exposed to different concentrations (0.2%, 0.3%, and 0.6%) of Se‐AgNPs which showed largest zone (12 ± 1 mm) of inhibition for 0.4% of Se‐AgNPs against Protius mirabilis and smallest zone (5 ± 1.154 mm) for 0.3% of Se‐AgNPs against Escherichia coli. Furthermore, effect of different temperatures (5°C, 37°C, and 60°C) and pH (3, 7, and 12) on the efficacy and stability of Se‐AgNPs was also evaluated against different bacterial strains. Sonication mediated NPs showed highest bactericidal results against K. pneumoniae (F3,8 = 6.154; p = 0.018) with smallest size NPs (7.49 nm) while lowest bactericidal results against S. rubidaea (5 ± 1 mm) were shown with largest size (78.12 nm) NPs prepared by natural light. These variations of bactericidal activities of NPs with difference size endorse that the Se‐AgNPs with smallest size have highest antibacterial activity than larger size NPs. Moreover, Se‐AgNPs maintain their bactericidal potency at wide range of temperature and pH, hence seemed stable. [ABSTRACT FROM AUTHOR]

Silk, a natural compound of silkworm contains two proteins, sericin and fibroin. These proteins can be conjugated with other compounds to form silk-derived nanoparticles. The biomedical applications of silk-based nanoparticles for drug delivery and cancer treatment are arising as they are biocompatible, biodegradable, have enhanced permeability and retention effect and less toxicity. Nevertheless, not a single review of literature is present that could describe the anticancer potential of silk derived nanoparticles. In this review, we describe the (i) comprehensive note on fibroin and sericin based nanoparticles (ii) anticancer mechanistic accompanied by biomedical applications in diagnosis, imaging, and drug delivery. [ABSTRACT FROM AUTHOR]