Environmental biodegradability of recombinant structural protein

Next generation polymers needs to be produced from renewable sources and to be converted into inorganic compounds in the natural environment at the end of life. Recombinant structural protein is a promising alternative to conventional engineering plastics due to its good thermal and mechanical properties, its production from biomass, and its potential for biodegradability. Herein, we measured the thermal and mechanical properties of the recombinant structural protein BP1 and evaluated its biodegradability. Because the thermal degradation occurs above 250 °C and the glass transition temperature is 185 °C, BP1 can be molded into sheets by a manual hot press at 150 °C and 83 MPa. The flexural strength and modulus of BP1 were 115 ± 6 MPa and 7.38 ± 0.03 GPa. These properties are superior to those of commercially available biodegradable polymers. The biodegradability of BP1 was carefully evaluated. BP1 was shown to be efficiently hydrolyzed by some isolated bacterial strains in a dispersed state. Furthermore, it was readily hydrolyzed from the solid state by three isolated proteases. The mineralization was evaluated by the biochemical oxygen demand (BOD)-biodegradation testing with soil inocula. The BOD biodegradability of BP1 was 70.2 ± 6.0 after 33 days.

Bioplastic Biodegradation Based on Ganyong Umbi States with Addition of Sorbitol and CMC (Carboxy Methil Cellulose) In Soil Media

Bioplastics made using the basic ingredients of canna tuber starch with sorbitol plasticizer and the addition of CMC variations have been carried out. This study aims to understand the effect of adding CMC to the mechanical properties and biodegradability of bioplastics in soil media. This research was carried out with 4 stages of work namely, extraction of starch from canna tubers, synthesis of bioplastic manufacturing using the blending method, testing mechanical properties in the form of thickness, tensile strength, elongation, and young modulus. Characteristics of functional groups have been tested using FTIR and bioplastic biodegradability testing has been carried out on soil media for 21 days by looking at weight loss from bioplastics. The variation of adding CMC used is 0; 0.25; 0.5; 0.75; 1; 1.25; 1.5 and 2 grams. The best mechanical properties are produced with thickness of 0.0795 mm, tensile strength of 27.53 MPa, elongation of 3.018% and young modulus of 885.66 MPa. The results of bioplastic biodegradation testing on soil media for 21 days showed that bioplastics made were biodegradable. Reduction of bioplastic mass in soil media by 86,032%.

The Effect of Cassava Peel Starch Addition to Bioplastic Biodegradation Based On Chitosan On Soil and River Water Media

The study of the relationship between starch addition to biodegradation of bioplastics has been carried out. This study aims to understand the biodegradability of chitosan-based bioplastics with additional cassava peel starch on soil and river water media. This research was conducted through four stages, namely making starch from cassava peel waste, making bioplastics using the blending and castingwet processes method with variations of starch 5, 10, 15 and 20 ml. Testing physical mechanical properties including water resistance, thickness, tensile strength, elongation, and modulus young. Testing the characteristics of bioplastics functional groups was carried out using FTIR (Fourier Transform Infrared) and biodegradation testing of bioplastics carried out on soil and river water media. The results of bioplastics research with variation 5 ml produce good mechanical physical properties. Bioplastics produced water resistance value of 45.03%, thickness of 0.0190 mm, tensile strength of 49.93 MPa, elongation of 3.068% and Young modulus of 1627.63 MPa. Bioplastics biodegradation test was observed by measuring the decrease in sample mass. The biodegradation test results in soil and river water media respectively showed a decrease in bioplastic mass up to 63% and 54%. The biodegradation rate of the calculation results on soil media is −0,1502 and in river water media is −0,0948.

A simple field-based biodegradation test shows pH to be an inadequately controlled parameter in laboratory biodegradation testing

We developed a field-based biodegradation test based on OECD 309 which minimizes the need for laboratory resources. Significant differences in biodegradation rates were observed between parallel lab and field tests likely due to pH disparities.

How Green is Your Plasticizer?

Plasticizers are additives that are used to impart flexibility to polymer blends and improve their processability. Plasticizers are typically not covalently bound to the polymers, allowing them to leach out over time, which results in human exposure and environmental contamination. Phthalates, in particular, have been the subject of increasing concern due to their established ubiquity in the environment and their suspected negative health effects, including endocrine disrupting and anti-androgenic effects. As there is mounting pressure to find safe replacement compounds, this review addresses the design and experimental elements that should be considered in order for a new or existing plasticizer to be considered green. Specifically, a multi-disciplinary and holistic approach should be taken which includes toxicity testing (both in vitro and in vivo), biodegradation testing (with attention to metabolites), as well as leaching studies. Special consideration should also be given to the design stages of producing a new molecule and the synthetic and scale-up processes should also be optimized. Only by taking a multi-faceted approach can a plasticizer be considered truly green.