Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli

In this study, restaurant waste was utilized as sole carbon source for the production of polyhydroxybutyrate (PHB) by recombinant Escherichia coli. PHB production was achieved via a two-stage process; organic acids production from fermented restaurant waste followed by PHB production utilizing the o...

Full description

Saved in:
Bibliographic Details
Main Author: Eshtaya, Majd Khalid
Format: Thesis
Language:English
English
Published: 2007
Subjects:
Online Access:http://psasir.upm.edu.my/id/eprint/5227/1/FK_2007_34.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
id my-upm-ir.5227
record_format uketd_dc
spelling my-upm-ir.52272013-05-27T07:21:18Z Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli 2007 Eshtaya, Majd Khalid In this study, restaurant waste was utilized as sole carbon source for the production of polyhydroxybutyrate (PHB) by recombinant Escherichia coli. PHB production was achieved via a two-stage process; organic acids production from fermented restaurant waste followed by PHB production utilizing the organic acids. In the first stage, the effect of initial pH, operating temperature and enzymatic pretreatment (hydrolysis using α-amylase and glucoamylase) were investigated to get highest organic acids production from restaurant wastes in anaerobic treatment. Anaerobic treatment was carried out in 500 mL Erlenmeyer flask using orbital shaking incubator. Three different temperatures were chosen; 30°C, 37°C and uncontrolled (room temperature). The initial pH of fermentation was also varied; adjusted at 7 and without adjustment. The organic acids produced were maximum (66 g/L) on the fifth day of fermentation that was carried out at 37°C, initial pH adjustment at 7 and enzymatic pretreatment with the yield of 0.723 g organic acids/g initial COD. The main organic acids produced was acetic acid (50%),followed by lactic acid (33%), iso-butyric acid (9%) and n-butyric acids (8%). The results indicate that high concentration of organic acids were produced in anaerobic treatment of restaurant wastes, which could served as alternative and abundant substrate for the production of biodegradable plastics. The supernatant collected from the anaerobic treatment of highest organic acids production was concentrated by vacuum evaporation to be used for PHB production. The total organic acids obtained after evaporation process was about 100 g/L. In the second stage, the concentrated organic acids were successfully converted to PHB using batch and pH-stat fed-batch fermentation by recombinant Escherichia coli containing. In batch fermentation about 6.8 g/L of cell dry weight and 2.5 g/L of PHB were achieved after 18 hours of cultivation, resulting in PHB content of 36% and productivity of PHB 0.14 g L-1 h-1. On the other hand, the maximum PHB concentration obtained was 9.2 g/L after 17 hours corresponding to 44% (g/g) of PHB content and 0.539 g L-1 h-1 productivity in pH-stat fed-batch fermentation. Waste products - Malaysia 2007 Thesis http://psasir.upm.edu.my/id/eprint/5227/ http://psasir.upm.edu.my/id/eprint/5227/1/FK_2007_34.pdf application/pdf en public masters Universiti Putra Malaysia Waste products - Malaysia Faculty of Engineering English
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
English
topic Waste products - Malaysia


spellingShingle Waste products - Malaysia


Eshtaya, Majd Khalid
Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
description In this study, restaurant waste was utilized as sole carbon source for the production of polyhydroxybutyrate (PHB) by recombinant Escherichia coli. PHB production was achieved via a two-stage process; organic acids production from fermented restaurant waste followed by PHB production utilizing the organic acids. In the first stage, the effect of initial pH, operating temperature and enzymatic pretreatment (hydrolysis using α-amylase and glucoamylase) were investigated to get highest organic acids production from restaurant wastes in anaerobic treatment. Anaerobic treatment was carried out in 500 mL Erlenmeyer flask using orbital shaking incubator. Three different temperatures were chosen; 30°C, 37°C and uncontrolled (room temperature). The initial pH of fermentation was also varied; adjusted at 7 and without adjustment. The organic acids produced were maximum (66 g/L) on the fifth day of fermentation that was carried out at 37°C, initial pH adjustment at 7 and enzymatic pretreatment with the yield of 0.723 g organic acids/g initial COD. The main organic acids produced was acetic acid (50%),followed by lactic acid (33%), iso-butyric acid (9%) and n-butyric acids (8%). The results indicate that high concentration of organic acids were produced in anaerobic treatment of restaurant wastes, which could served as alternative and abundant substrate for the production of biodegradable plastics. The supernatant collected from the anaerobic treatment of highest organic acids production was concentrated by vacuum evaporation to be used for PHB production. The total organic acids obtained after evaporation process was about 100 g/L. In the second stage, the concentrated organic acids were successfully converted to PHB using batch and pH-stat fed-batch fermentation by recombinant Escherichia coli containing. In batch fermentation about 6.8 g/L of cell dry weight and 2.5 g/L of PHB were achieved after 18 hours of cultivation, resulting in PHB content of 36% and productivity of PHB 0.14 g L-1 h-1. On the other hand, the maximum PHB concentration obtained was 9.2 g/L after 17 hours corresponding to 44% (g/g) of PHB content and 0.539 g L-1 h-1 productivity in pH-stat fed-batch fermentation.
format Thesis
qualification_level Master's degree
author Eshtaya, Majd Khalid
author_facet Eshtaya, Majd Khalid
author_sort Eshtaya, Majd Khalid
title Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
title_short Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
title_full Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
title_fullStr Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
title_full_unstemmed Production Of Organic Acids From Restaurant Wastes As Substrates For Polyhydroxybutyrate Production By Recombinant E. Coli
title_sort production of organic acids from restaurant wastes as substrates for polyhydroxybutyrate production by recombinant e. coli
granting_institution Universiti Putra Malaysia
granting_department Faculty of Engineering
publishDate 2007
url http://psasir.upm.edu.my/id/eprint/5227/1/FK_2007_34.pdf
_version_ 1747810378290561024