Plastics are becoming a more prevalent concern in our world. Recently, it has been estimated that 8,300 billion metric tons of plastic have been produced to date (Geyer, Jambeck, & Law, 2017). Of those plastics, polyethylene (PE) plastics are the most common. Examples of these include LDPE (low density polyethylene) and linear LDPE which are used in saran wrap and plastic bags, respectively. However, to achieve their durability, PE plastics use chemicals that ultimately cause a longer degradation period and simultaneously harm the environment. In the past few decades, researchers have experimented with bioplastics, plastic materials made with renewable resources, to possibly replace traditional plastics. Because of the many harmful implications of traditional plastics, my project aims to create a bioplastic film made from mealworm-derived chitin and chitosan with starch.

Chitin is a derivative of glucose that creates the exoskeletons or hard casing of arthropods such as crustaceans or insects. Chitosan comes from chitin through the process of deacetylation, Essentially, they are the same product, but chitosan is chitin without the acetyl groups. Although the idea of chitin, chitosan, and starch blended bioplastics is not a novel idea, to date, there has not been any starch and mealworm-derived chitin and chitosan created, which is what this project aims to achieve.

Usually, chitin and chitosan bioplastics are inefficient as only 10-15% of arthropod shells contain chitin, and many chemicals and energy sources are required. Conversely, mealworm exoskeletons are simply grinded and the process is cruelty-free. Mealworms are also small, easy to maintain, have a quick life-cycle, and can subsist on a variety of diets. In fact, recent studies from

Stanford researchers record that mealworms can thrive on an unconventional diet of solely polystyrene, a plastic that never degrades, successfully convert half of the plastic into carbon dioxide, which is similar to any other food source, and have no significant health effects (Brandon, Abbadi, Ibekwe, Cho, Wu, & Criddle 2019). The exoskeletons of these plastic-eating mealworms are used as a source of chitin and chitosan. The exoskeletons were washed, grinded, deproteinized with 3.0 M sodium hydroxide, demineralized by 1.25 M HCl, dried, deacetylated with NaOH, combined with cornstarch and glycerol plasticizer, and cast to dry at ambient temperature to produce bioplastics.

The bioplastics were then assessed using the tests of Ultimate Tensile Strength, Soil Biodegradation, and Solubility. Compared to the standardized tensile strength values of LDPE and linear LDPE plastics, the bioplastic with corn starch and chitosan solution was comparable, being within the range of 1,360-1,600 and 1,600-1,800 psi of the plastics, respectively. Within the soil biodegradability test, the bioplastic mass was shown to have decreased over the span of five days, and bioplastics were all found to be insoluble. With the comparable strength and characteristics, this project yields positive implications as a possible model for a novel bioplastic made from worms that eat plastic.