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Production of Bioplastic Polyhydroxyalkanoates (PHA) Utilizing Cheese Processing Byproducts by Halophilic Microbes /

Record Type:	Electronic resources : Monograph/item
Title/Author:	Production of Bioplastic Polyhydroxyalkanoates (PHA) Utilizing Cheese Processing Byproducts by Halophilic Microbes // Alexander Hobby.
Author:	Hobby, Alexander,
Description:	1 electronic resource (308 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 85-06, Section: B.
Contained By:	Dissertations Abstracts International85-06B.
Subject:	Bioengineering. -
Online resource:	https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=30640136
ISBN:	9798381110333

Production of Bioplastic Polyhydroxyalkanoates (PHA) Utilizing Cheese Processing Byproducts by Halophilic Microbes /
Hobby, Alexander,

Production of Bioplastic Polyhydroxyalkanoates (PHA) Utilizing Cheese Processing Byproducts by Halophilic Microbes /Alexander Hobby. - 1 electronic resource (308 pages)

Source: Dissertations Abstracts International, Volume: 85-06, Section: B.

Plastic products have become indispensable in various industrial sectors and everyday life worldwide. However, conventional plastics present significant sustainability challenges due to their reliance on unsustainable petroleum sources, contribution to greenhouse gas emissions, and their resistance to biodegradation, which leads to environmental waste accumulation. In response to these issues and the need to decrease carbon emissions, there has been a growing interest in bioplastics. One promising family of bioplastics is polyhydroxyalkanoate (PHA), a group of natural polyesters that can serve as a sustainable alternative to traditional plastics in numerous applications. PHA stands out among bioplastics for several reasons, including production from organic waste substrates. The polyester can be produced from various organic waste materials, reducing the demand for costly virgin resources and providing an environmentally friendly solution for waste management. PHA additionally possesses high biodegradability compared to other bioplastics on the market, allowing it to break down more efficiently in the environment and minimize long-term pollution. PHA can replace several families of petroleum-based plastics, making it a versatile option for a wide range of products and applications. However, despite these promising attributes, the high production cost of PHA remains a significant barrier to its widespread adoption. The expensive carbon sources utilized in microbial fermentation are the primary factor contributing to this cost, limiting the growth of the PHA market. There is a critical need to develop an efficient bioprocessing system that can produce high-quality PHA at a significantly lower cost. To address this imperative, the primary goal of this study was to create an integrated PHA production system that utilizes inexpensive cheese byproducts feedstock, making PHA production more economically viable while maximizing resource efficiency and minimizing waste.Whey and whey byproducts generated from cheese production offer a promising source for bioplastic production. Researchers estimate that approximately half of this whey produced from cheese making is processed into useful forms for human or animal consumption, with the rest ending up as waste material, contributing to high carbon emissions. While some cheese manufacturers can convert whey byproducts into valuable food ingredients, like whey protein concentrates and lactose powder, additional byproducts continue to be generated. Whey permeate is produced after concentrating the liquid whey with membrane filtration, containing most of the lactose and minerals. The whey permeate can be further processed into lactose powder with evaporation and drying systems creating byproduct delactosed permeate (DLP). Crystallization limitations prevent the complete recovery of lactose for food products. As a result, approximately one-third of the lactose remains as delactosed permeate (DLP), which is either sold as low-value animal feed or disposed of as waste. DLP is the main cheese byproduct without a widespread commercial application, which presents an opportunity for biomaterial production. Therefore, this study aimed to convert low-value cheese byproducts DLP into high-value bioplastic PHA.The PHA producer Haloferax mediterranei (H. mediterranei) appears to be a suitable candidate for utilizing cheese byproducts as feedstock. This fit is due to the archaea's unique ability to thrive in extreme halophilic conditions, tolerating salinity levels of up to 20%. The presence of high salt-containing cheese byproducts provides a compatible source of nutrients for H. mediterranei, compared to other PHA producers and common contaminant organisms that can become inhibited from such high salt concentrations. The high salt environment removes the need for an expensive sterility unit operation, such as high-temperature exposure or antibiotics, reducing production costs. Moreover, the intracellular PHA extraction from H. mediterranei can be achieved through a straightforward process of water addition, causing osmotic shock and cell lysis. High salt-containing cheese byproducts provide Another advantage of H. mediterranei is its ability to produce a higher-value PHA polyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). This PHA polyester exhibits enhanced properties compared to the more commonly produced polyhydroxybutyrate (PHB). The presence of 3-hydroxyvalerate units in PHBV enhances its flexibility, making it suitable for various applications, especially in the food industry. The potential applications of PHBV in food packaging, such as films, bags, containers, or cutlery, align with the circular economy principles. By utilizing cheese byproducts and producing high-value PHBV, the cheese industry can take significant steps toward sustainability and waste reduction.A pretreatment method of the DLP was developed and optimized utilizing centrifugation and enzymatic lactase hydrolysis. The centrifugation pretreatment was shown to increase lactase hydrolysis efficiency and H. mediterranei cell growth. The optimal lactase enzyme conditions with the centrifuged DLP to achieve a lactose hydrolysis efficiency of 92.5% were determined to be a loading of 0.025 g lactase/g lactose and shaking incubation at 40 ℃ for 12 hours. The effects of hydrolyzed DLP on H. mediterranei cell growth and PHA production were studied. (Abstract shortened by ProQuest).

English

ISBN: 9798381110333Subjects--Topical Terms:

657580
Bioengineering.
Subjects--Index Terms:

Cheese byproduct

Production of Bioplastic Polyhydroxyalkanoates (PHA) Utilizing Cheese Processing Byproducts by Halophilic Microbes /
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520 $a Plastic products have become indispensable in various industrial sectors and everyday life worldwide. However, conventional plastics present significant sustainability challenges due to their reliance on unsustainable petroleum sources, contribution to greenhouse gas emissions, and their resistance to biodegradation, which leads to environmental waste accumulation. In response to these issues and the need to decrease carbon emissions, there has been a growing interest in bioplastics. One promising family of bioplastics is polyhydroxyalkanoate (PHA), a group of natural polyesters that can serve as a sustainable alternative to traditional plastics in numerous applications. PHA stands out among bioplastics for several reasons, including production from organic waste substrates. The polyester can be produced from various organic waste materials, reducing the demand for costly virgin resources and providing an environmentally friendly solution for waste management. PHA additionally possesses high biodegradability compared to other bioplastics on the market, allowing it to break down more efficiently in the environment and minimize long-term pollution. PHA can replace several families of petroleum-based plastics, making it a versatile option for a wide range of products and applications. However, despite these promising attributes, the high production cost of PHA remains a significant barrier to its widespread adoption. The expensive carbon sources utilized in microbial fermentation are the primary factor contributing to this cost, limiting the growth of the PHA market. There is a critical need to develop an efficient bioprocessing system that can produce high-quality PHA at a significantly lower cost. To address this imperative, the primary goal of this study was to create an integrated PHA production system that utilizes inexpensive cheese byproducts feedstock, making PHA production more economically viable while maximizing resource efficiency and minimizing waste.Whey and whey byproducts generated from cheese production offer a promising source for bioplastic production. Researchers estimate that approximately half of this whey produced from cheese making is processed into useful forms for human or animal consumption, with the rest ending up as waste material, contributing to high carbon emissions. While some cheese manufacturers can convert whey byproducts into valuable food ingredients, like whey protein concentrates and lactose powder, additional byproducts continue to be generated. Whey permeate is produced after concentrating the liquid whey with membrane filtration, containing most of the lactose and minerals. The whey permeate can be further processed into lactose powder with evaporation and drying systems creating byproduct delactosed permeate (DLP). Crystallization limitations prevent the complete recovery of lactose for food products. As a result, approximately one-third of the lactose remains as delactosed permeate (DLP), which is either sold as low-value animal feed or disposed of as waste. DLP is the main cheese byproduct without a widespread commercial application, which presents an opportunity for biomaterial production. Therefore, this study aimed to convert low-value cheese byproducts DLP into high-value bioplastic PHA.The PHA producer Haloferax mediterranei (H. mediterranei) appears to be a suitable candidate for utilizing cheese byproducts as feedstock. This fit is due to the archaea's unique ability to thrive in extreme halophilic conditions, tolerating salinity levels of up to 20%. The presence of high salt-containing cheese byproducts provides a compatible source of nutrients for H. mediterranei, compared to other PHA producers and common contaminant organisms that can become inhibited from such high salt concentrations. The high salt environment removes the need for an expensive sterility unit operation, such as high-temperature exposure or antibiotics, reducing production costs. Moreover, the intracellular PHA extraction from H. mediterranei can be achieved through a straightforward process of water addition, causing osmotic shock and cell lysis. High salt-containing cheese byproducts provide Another advantage of H. mediterranei is its ability to produce a higher-value PHA polyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). This PHA polyester exhibits enhanced properties compared to the more commonly produced polyhydroxybutyrate (PHB). The presence of 3-hydroxyvalerate units in PHBV enhances its flexibility, making it suitable for various applications, especially in the food industry. The potential applications of PHBV in food packaging, such as films, bags, containers, or cutlery, align with the circular economy principles. By utilizing cheese byproducts and producing high-value PHBV, the cheese industry can take significant steps toward sustainability and waste reduction.A pretreatment method of the DLP was developed and optimized utilizing centrifugation and enzymatic lactase hydrolysis. The centrifugation pretreatment was shown to increase lactase hydrolysis efficiency and H. mediterranei cell growth. The optimal lactase enzyme conditions with the centrifuged DLP to achieve a lactose hydrolysis efficiency of 92.5% were determined to be a loading of 0.025 g lactase/g lactose and shaking incubation at 40 ℃ for 12 hours. The effects of hydrolyzed DLP on H. mediterranei cell growth and PHA production were studied. (Abstract shortened by ProQuest).
546 $a English
590 $a School code: 0029
650 4 $a Bioengineering. $3 657580
650 4 $a Agricultural engineering. $3 3168406
650 4 $a Engineering. $3 586835
650 4 $a Plastics. $3 649803
650 4 $a Systems science. $3 3168411
653 $a Cheese byproduct
653 $a Delactosed permeate
653 $a Haloferax mediterranei
653 $a Halophile
653 $a Polyhydroxyalkanoates
653 $a Whey pemeate
690 $a 0539
690 $a 0202
690 $a 0795
690 $a 0537
690 $a 0790
710 2 $a University of California, Davis. $b Biological Systems Engineering. $e degree granting institution. $3 3818627
720 1 $a Zhang, Ruihong $e degree supervisor.
773 0 $t Dissertations Abstracts International $g 85-06B.
790 $a 0029
791 $a Ph.D.
792 $a 2023
856 4 0 $u https://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=30640136