With the rise in antibiotic resistance, researchers are looking into local environments to source pharmaceuticals from plant materials. One source that is little explored is the medicinal plants used in Indigenous communities. California State University, Channel Islands (CSUCI) is built on unceded Chumash land. As a result, our institution has the privilege of collaborating with local Chumash communities to steward the land's natural and cultural ancestry. The exercise we developed utilizes the Kirby-Bauer disk diffusion assay (KB assay), a standard laboratory technique focused on testing the effectiveness of various antibiotics on bacterial cultures. However, instead of antibiotics, we utilize plant extracts derived from Native California species, associated with Chumash medicine in recognition of CSUCI’s relationship with the Chumash. In addition to testing local medicinal plants, this activity aimed to increase the students’ sense of belonging. During the lab activity, students discuss antibiotic resistance's impact and holistic discovery's role in creating new pharmaceuticals. Students also examine how their cultural and familial teachings may be a source of scientific/academic inquiry. Then, they perform the KB assay using prepared extracts and antibiotics. Students then interpret the Zones of Inhibition (ZOI) for each extract (Wild buckwheat and Rue) and antibiotics (Tetracycline and Amoxicillin/ Clavulanic Acid), comparing them to cut-offs provided by the Clinical Laboratory Science Institute (CLSI) to determine the bacterial strains’ susceptibility. Most plant extracts were proven ineffective against our bacterial strains- E.coli, P. fluorescens, and B. subtilis. However, the Rue extract showed intermediate and susceptible results against Bacillus subtilis. Nevertheless, through this lab exercise students engaged in a novel method for a standardized microbiology technique and expressed their feelings of belonging in survey-based feedback. In the future, we hope to analyze the survey responses and classroom engagement to foster increased belonging in STEM among diverse groups of students.
