# An Overview of the Alternative Use of Seaweeds to Produce Safe and Sustainable Bio-Packaging
## 1 Introduction
Cellulose is a low-cost, biodegradable and water-insoluble material that is promising for the development of biodegradable films [24; 32]. It is the most abundant biomass resource on earth, and is found in plants, fruits, and vegetables [33]. Cellulose derivates, such as hydroxypropyl methylcellulose (HPMC) and methylcellulose (MC), have been used to form biofilm due to their mechanical resistance [34]. Moreover, the methyl group substitution to the cellulose backbone led to the solubility of HPMC and MC in cold water; thus, when heated, they form a gel, while in cold water they are soluble. Both HPMC and MC are potential compounds for the production of strong, clear, odourless, tasteless, oil-resistant, and water-soluble films [21]. [PERSON] et al. [35] recently developed a new biofilm using the whole fruit. The use of papaya has been promoted for its strong photoproduction activity, as the UV screening capacity of food packaging film is beneficial to prevent spoiled food. The UV transmittance of developed films was calculated; papaya film (a mixture of gelatin, papaya, corn starch, and glycerin) revealed the highest transmittance compared to film with soy protein addition, as was the case for the combination of glycerol and gelatine. Moreover, papaya film exhibited higher transparency and elasticity, and slower degradability, compared to film with soy proteins. In conclusion, papaya biofilm revealed effective UV protection properties and qualities that makes it comparable to commercial plastic films. On the other hand, macroalgae have more potential as a source of bioplastics due to their higher biomass, fast reproduction, they are easily maintained in all environments, and are cost-effective [20]. In addition to their biodegradability property, seaweed-derived biofilms might exhibit antimicrobial activities, as seaweeds produce antimicrobial compounds, identified as phenols, fatty acids, carbohydrates, proteins, and minor compounds [36; 37; 38; 39; 40], which take part in mechanisms of antibiotic defence developed to survive the harsh environments seaweeds inhabit. The integration of the whole seaweed, or seaweed extracts, with antimicrobial activity in food packaging manufacture might increase the shelf-life of foods and prevent the development of foodborne pathogens. A recently published study by [PERSON] et al. [41] listed the main antimicrobial compounds recently isolated from multiple seaweeds and their main antimicrobial properties. Most compounds exhibit broad-spectrum antibiotic activity, confirming seaweed has the potential to shield against microbes and foodborne pathogens. This review aims to provide a better understanding of seaweeds as a potential resource used to produce biodegradable and antibacterial plastic. Seaweed-derived biological compounds, such as carrageenan, agar, and alginate, possess unique physical, optical, mechanical, thermal, antioxidant, and antibacterial properties, and the biodegradability of seaweed-derived bioactive compounds make them ideal candidates to produce bioplastic packaging for medicine and food.