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Fabrication, characterization and evaluation of the larvicidal potential of novel silk protein (sericin)‐based silver nanoparticles (Se‐AgNPs) were the prime motives of the designed study. Furthermore, investigation of the sericin as natural reducing or stabilizing agent was another objective behind this study. Se‐AgNPs were synthesized using sonication and heat. Fabricated Se‐AgNPs were characterized using particle size analyzer, UV spectrophotometry, FTIR and SEM which confirmed the fabrication of the Se‐AgNPs. Size of sonication‐mediated Se‐AgNPs was smaller (7.49 nm) than heat‐assisted Se‐AgNPs (53.6 nm). Being smallest in size, sonication‐assisted Se‐AgNPs revealed the significantly highest (F4,10 = 39.20, p =.00) larvicidal activity against fourth instar lab and field larvae (F4,10 = 1864, p =.00) of dengue vector (Aedes aegypti) followed by heat‐assisted Se‐AgNPs and positive control (temephos). Non‐significant larvicidal activity was showed by silver (without sericin) which made the temperature stability of silver, debatable. Furthermore, findings of biochemical assays (glutathione‐S transferase, esterase, and acetylcholinesterase) showed the levels of resistance in field strain larvae. Aforementioned findings of the study suggests the sonication as the best method for synthesis of Se‐AgNPs while the larvicidal activity is inversely proportional to the size of Se‐AgNPs, i.e., smallest the size, highest the larvicidal activity. Conclusively, status of the sericin as a natural reducing/stabilizing agent has been endorsed by the findings of this study. Research Highlights: Incorporation of biocompatible and inexpensive sericin as a capping/reducing agent for synthesis of Se‐AgNPs.A novel sonication method was used for the fabrication of Se‐AgNPs which were thoroughly characterized by particle size analyzer, UV–visible spectrophotometry, SEM and FTIR.Analysis of enzymatic (GSTs, ESTs) levels in field and lab strains of Aedes aegypti larvae for evaluation of insecticides resistance. [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]

The antibacterial activity of synthetic antimicrobial agents is well known, but most of them have several side effects and are effective against selective microbes. Recently, major concern for the microbiologists is to investigate for some stable, non‐toxic, cheap, and eco‐friendly antimicrobial agents with a wide range of bactericidal potential. A cost‐effective and environmentally friendly alternate has been proposed in the form of green synthesized nanoparticles. The Present study was designed to fabricate sericin‐coated silver nanoparticles (S‐AgNPs) using sericin as stabilizer and reductant of silver ions and their antibacterial potential was evaluated at various concentrations and temperatures (8, 40, and 50°C). Antimicrobial activities were assessed by the agar well diffusion method. Antibacterial activity of S‐AgNPs was measured at different concentrations (1–6 mg/ml) whereas; antifungal activity was tested at 5–20 mg/ml of S‐AgNPs. Nanoparticles were characterized by UV–visible spectrophotometer, Fourier transform infrared spectroscopy, and scanning electron microscopy. These nanoparticles significantly subdued the growth of Clostridium difficile (18.7 ± 0.9 mm), Proteus mirabilis (12.3 ± 0.3 mm) and Bacillus licheniformis (10.7 ± 0.9 mm) and Aspergillus flavus (18.7 ± 2.0 mm), Mucor mycetes (13.0 ± 1.5 mm), Candida albicans (15.3 ± 0.3 mm) and Aspergillus niger (10.0 ± 0.6 mm). S‐AgNPs were stable at all temperatures and the maximum growth inhibition was found at 8°C for all pathogenic strains. We concluded that the S‐AgNPs could be a potential candidate to inhibit the growth of bacterial and fungal pathogens at a wide range of environmental conditions like temperature. In various biomedical applications including antimicrobial and wound dressings, S‐AgNPs can be used in the future to treat various bacterial and fungal infections. [ABSTRACT FROM AUTHOR]

Background: Thalassemia is an inherited hematological disorder categorized by a decrease or absence of one or more of the globin chains synthesis. Beta‐thalassemia is caused by one or more mutations in the beta‐globin gene. The absence or reduced amount of beta‐globin chains causes ineffective erythropoiesis which leads to anemia. Methods: Beta‐thalassemia has been further divided into three main forms: thalassemia major, intermedia, and minor/silent carrier. A more severe form among these is thalassemia major in which individuals depend upon blood transfusion for survival. The high level of iron deposition occurs due to regular blood transfusion therapy. Results: Overloaded iron raises the synthesis of reactive oxygen species (ROS) that are noxious and prompting the injury to the hepatic, endocrine, and vascular system. Thalassemia can be analyzed and diagnosed via prenatal testing (genetic testing of amniotic fluid), blood smear, complete blood count, and DNA analysis (genetic testing). Treatment of thalassemia intermediate is symptomatic; however; it can also be accomplished by folic supplementation and splenectomy. Conclusion: Thalassemia major can be cured through regular transfusion of blood, transplantation of bone marrow, iron chelation management, hematopoietic stem cell transplantation, stimulation of fetal hemoglobin production, and gene therapy. [ABSTRACT FROM AUTHOR]

Abstract: High level of heavy metal contaminants in air is known to cause serious health problems if remained unchecked for a long period of time. Anthropogenic activities such as vehicular emissions and number of industries are responsible for increasing the level of heavy metals. The aim of the present study was to biologically monitor the level of heavy metal contamination by spider webs. These sites were selected based on variable traffic volume and number of industries. Atomic absorption spectrometry (AAS) was used for the analysis of metal pollution content. The study determined that the level of heavy metals at the selected sampling sites were several folds higher than that at the control site and in previously reported literature. Pb was determined to be the most abundant heavy metal, while Thokar Niaz Baig was reported as the most contaminated site. These elevated levels of metal contaminants are associated with heavy traffic flow, number of industries and constructional activities in the respective areas. [ABSTRACT FROM AUTHOR]