Green Machineries as Biochemical Modifiers for Efficient Agricultural Raw Materials

[ACSGCI]

Contributed by Faiza Rasheed, Department of Plant Breeding, The Swedish University of Agricultural Sciences, Alnarp, Sweden

With the much advocated issue related to limited fossil fuel resources in future and the deleterious impacts of fossil fuel derived products on environment, there is an increasing attention towards the development of ‘’sustainable products’’ in many areas such as plastics, elastomers, chemicals, and more. How can we meet this increasing demand when natural resources are limited? It could be done by developing new sustainable production methods by using existing machineries or even with  nature’s own ‘’green machineries.’’

In our recent study led by Prof. Eva Johansson in the Dept. of Plant Breeding, The Swedish University of Agricultural Sciences, Alnarp, we used ‘’green machineries,’’ i.e. wheat plants as biochemical modifiers. The properties of protein, a biopolymer, were modified by the use of biological and environmental factors such as genotype, cultivation temperature and availability of fertilizers (Fig. 1.). The method provides a simple and sustainable design that can be employed on a broader scale to modify different polymers that are naturally synthesized by plants. These polymers could potentially be used to produce various products such as plastics, packaging materials, biofuel, dyes, etc. in order to replace certain petroleum based products. For instance, the protein polymer produced in our study was used to make plastic films (Fig. 2), and a unique combination of strength and elasticity was achieved in these films which are much needed properties for today’s packaging industry. In our method we used the plants to modify and strengthen the wheat gluten proteins in natural way without the need for synthetic chemicals. Furthermore, proteins offer a broad range of chemical diversity as their composing units, amino acids, are diverse with respect to configurations and chemical functional groups. This means that they offer a large spectrum of chemical versatilities to fine-tune the properties of end-use products.

In our study we tuned the structure of gluten proteins with genotype and environmental interaction and also extracted gluten in a milder way, avoiding solvents and high drying temperature which preserved the native structure of gluten. The pristine gluten structure resulted into hierarchal nano-structural arrangements which were not observed before for gluten that has been modified into films. We carried out the nano-structural characterization together with Dr. Tomás S. Plivelic at MAX IV Laboratory, Lund, a Swedish national laboratory with the most brilliant X-rays for research. Our study helped to model a relationship between the nano-structure of gluten from various genotypes and environmental interactions and resulting mechanical properties such as strength, stiffness and elasticity of films.

There is an on-going public and political debate related to the use of agricultural raw materials for the production of bio-based materials because there is some concern about chemical products competing with the food supply. While this debate may seem insurmountable, this issue must be addressed in a sensitive way as the facts are very different from popular belief. People have been using agricultural raw materials for the production of bio-based materials for a very long time. The issue is not the shortage of food or shortage of land for food production. The real issues are food distribution, logistics and customer purchasing power.

There are still huge unused arable areas that can be used to produce more food as well as efficient agricultural raw materials without any harmful impact or insecurity of supplies to the food sector. Using the arable land areas for industrial materials will not only reduce the environmental concerns related to fossil fuel derived products but will also raise the economic values of crops with a positive impact on the future bioeconomy. The question should not be which crops should be used for food and which ones for material production. Rather, it should be which crop is more sustainable, efficient and could contribute best to the bioeconomy for both the food and industrial use.

Using inefficient non-food crops for industrial uses will be an inefficient use of arable lands. There are also other ways to develop sustainable products from bio resources such as by the use of biotechnology and bioreactors to produce biopolymers at

massive scale. To me, efficient production and utilization of agricultural raw materials to derive “green products” can become a real game-changer as they show the potential of solving some large-scale problems related to fossil-fuel derived products.

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