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Microbial Biopolymers and Enzymes Involved in the Biosynthesis of PHAs

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Biodegradable Polymer-Based Food Packaging

Abstract

Biopolymers are natural alternatives for synthetic polymers which can be obtained from natural sources and represent themselves as sustainable solution for nondegradable plastic. Biopolymers are plastic-like substances obtained from organic sources that have applications in the development of reliable, nontoxic, but degradable packaging materials. Organic sources of hydrocolloids, polysaccharides, lipids, and protein have been used to extract biopolymers. However, recently microbial production of biopolymers has received much attention. Polyhydroxyalkanoates (PHAs) are intracellular granules produced by certain microorganisms under nutrient stress. Several bacterial species (Cupriavidus necator, Pseudomonas stutzeri, P. oleovorans, P. aeruginosa, and Bacillus megaterium) and many fungal and algal species are known for PHA production. Structural and regulatory genes for PHA synthesis are present in an operon in producing microorganisms with slight differences. PHAs have many applications in various industrial sectors such as food, agriculture, and pharmaceuticals. PHA can be exploited in several ways like biofuel generation as well as can be used in packaging material.

This chapter provides a comprehensive information of biopolymers and their composites, microbial biopolymers, and main biosynthetic pathways used for PHA production. Important aspects of PHAs, its biosynthesizing genes, and their relevant proteins have also been summarized.

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Authors and Affiliations

  1. Department of Dairy Science and Food Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, India

    Chhaya Goyal, Saloni Rai, Abhishek Dutt Tripathi & Dinesh Chandra Rai

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  1. Chhaya Goyal
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  2. Saloni Rai
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  3. Abhishek Dutt Tripathi
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  4. Dinesh Chandra Rai
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Correspondence to Chhaya Goyal .

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Editors and Affiliations

  1. Department of Dairy Science & Food Technology, Banaras Hindu University, Varanasi, Uttar Pradesh, India

    Abhishek Dutt Tripathi

  2. Department of Food Science and Technology, National Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran

    Kianoush Khosravi Darani

  3. Department of Dairy Science & Food Technology, Banaras Hindu University, Varanasi, India

    Dinesh Chandra Rai

  4. Department of Dairy Science & Food Technology, Banaras Hindu University, Varanasi, India

    Veena Paul

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Goyal, C., Rai, S., Tripathi, A.D., Rai, D.C. (2022). Microbial Biopolymers and Enzymes Involved in the Biosynthesis of PHAs. In: Dutt Tripathi, A., Darani, K.K., Rai, D.C., Paul, V. (eds) Biodegradable Polymer-Based Food Packaging. Springer, Singapore. https://doi.org/10.1007/978-981-19-5743-7_8

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