The most important characteristics of a perfect catalyst comprise simple design, good activity, excellent stability, easy recovery from the reaction mixture, recyclability, and the ability to scale up easily. The development of nanocatalysts using a biocompatible, phytochemical-assisted method for organic transformations and bioactivity studies has been relatively less explored. In this regard, we developed copper nanoparticles (Cu NPs) embedded on magnetite Fe3O4 as support, employing peel extract of Ananas comosus (ACPE) as a stabilizing, reducing, and capping agent (Fe3O4@ACPE@Cu). The ICP-OES demonstrated 9.26% w/w of Cu loading on the magnetite Fe3O4 support, with irregular morphology and well-dispersed elements, as confirmed by HR-TEM and HAADF analysis. The developed Fe3O4@ACPE@Cu nanocatalyst demonstrated impressive productivity in synthesizing various tetrazoles, yielding 96% for the model substrate. Additionally, a yield of 95% was observed for the model substrate used for the synthesis of 1-substituted benz(imidazole). Furthermore, the nanocatalyst demonstrated notable recyclability and remained effective for up to six consecutive cycles with no significant loss in catalytic activity in the subsequent cycle. In addition, both the support Fe3O4 and the Fe3O4@ACPE@Cu nanocatalyst showed promising results in colon cancer study, with excellent biocompatibility. Thus, the developed strategy integrates sustainable innovation and offers revolutionary solutions for organic transformations and medicinal chemistry.