الفهرس 
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Abstract
Nanotechnology is a rapidly growing field with potential applications in various fields ranging from semiconductor to cosmetics (Manikprabhu & Lingappa, 2014). Metallic nanoparticles, in particular, have gained attention due to their characteristic optical, thermal, electrical and catalytic properties (Burda et al., 2005). Among metallic nanoparticles, nanoscale silver particles have gained prime interest owing to their various biological activities and unusually enhanced physicochemical properties as compared to other metals in their nano form. Over decades, silver has been used to prevent and control disparate infections, nevertheless after the introduction of antibiotics in 1940s, the use of silver salts regressed.The huge development that nanoscience and nanotechnology experienced in recent years renowned the interest in silver. In the recent years, ongoing research has focused on preparation of silver nanoparticles (AgNPs) and application of their optical and biomedical properties in various fields (Ivanova et al., 2018).
Several chemical and physical methods have been adopted for the synthesis of AgNPs. Although these methods can successfully produce AgNPs efficiently, they have many drawbacks including the use of toxic and hazardous chemicals, high operational costs and energy requirements (Rani & Rajasekharreddy, 2011). Biological synthesis involving the use of plants, microorganisms and enzymes is becoming an alternative approach for the synthesis of nanoparticles. Among the bio-mediated synthesis of AgNPs, plant extracts are found to be suitable candidates over other biological entities. Plant based synthesis does not require toxic chemicals, high temperature, microbial strains and costly media and hence avoid the chance of infection and contamination during synthesis and applications. Various plant resources have been explored by researchers till date to synthesize AgNPs since plants are known to harbor a broad range of secondary metabolites which provide them the potential to act as reducing agents (Roy et al., 2019).
In context of plant-mediated synthesis of AgNPs, numerous herbs and spices have been evaluated as potential candidates. However edible plants did not receive such attention. Citrus plants, belonging to family Rutaceae, are among the most widely cultivated fruits globally (Mahato et al., 2018). According to the United States Department of Agriculture in 2017, Egypt is amongst the largest citrus fruit producers (USDA, 2017). Accordingly, huge amounts of wastes are generated every year. It was reported that more than 15.6 million tons of citrus peel waste are generated worldwide. These wastes that are mostly discarded into the environment may provide a potential platform for the production of chemically and biologically active compounds (Sharma et al., 2017).
Antimicrobial resistance has grown to be a concerning threat due to the rapid emergence of drug-resistance to recent antibiotics (Chandra et al., 2017). In the past, resistant infections were predominantly associated with hospitals and health care settings, but over the years they have been seen in the wider community too. The discouraged production of new antimicrobials further complicates the problem (Zaman et al., 2017). Antimicrobial resistance is not only considered merely as a global health threat but represents an economic burden too. In 2018, the Organization for Economic Co-operation and Development (OECD) has released a report which predicts that 2.4 million people in Europe, North America and Australia will die from infections with resistant microorganisms in the next 30 years and estimates the economic burden