Source: UNIV OF MINNESOTA submitted to
INTEGRATION OF BIOPRODUCTS AND BIOENERGY PRODUCTION WITH WASTE TREATMENT
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0223293
Grant No.
(N/A)
Project No.
MIN-12-037
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2010
Project End Date
Oct 1, 2013
Grant Year
(N/A)
Project Director
Hu, B.
Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108
Performing Department
Bioproducts & Biosystems Engineering
Non Technical Summary
Microalgae oil has been proposed as the second generation source to produce biofuel. Its use is highly recommended in order to integrate microalgae cultivation with wastewater treatment so that nutrients in the waste streams can be the raw material for microalgae growth. Some experts even argue that this might be the only option economically feasible, compared to other methods such as open ponds or photobioreactor systems. Anaerobic digestion (AD) has been widely commercialized to treat agricultural residues for nutrient release as well as for harvesting biogas as an energy source. AD converts organic N and P to ammonia and phosphate while total N and P remain constant. Microalgae cultured on the AD effluent usually provide an ideal combination with the AD to utilize the remaining N and P while biomass/oil can be accumulated via microalgae cultivation. However, this process faces several challenges: 1) it is of extremely low efficiency due to the slow growth of methanogens and autotrophic microalgae. The vulnerable nature of the methanogens makes the AD process constantly unstable, while the rich organic nutrients and high turbidity in the AD effluent actually inhibit microalgae to grow on sun light and CO2. 2) The biogas produced from the system consists over 50% impurities such as CO2 etc, which dramatically increase its application on high valued market. 3) The harvest of microalgae is energy-intensive, which is one of the major factors inhibiting the commercialization of the process. To solve the above mentioned issues, firstly, an integrated Anaerobic Digestion and Oil/Biomass Accumulation (ADOBA) process is proposed to combine the acitogenesis/fermentation stage of the anaerobic digestion (AD) process directly with the oil accumulation via mixotrophic microalgae or fungal cultivation. It is a simplified process, derived from common waste-water treatment processes such as AD or AD followed by microalgae cultivation in stabilization ponds (Fig. 1). Compared to these environmental processes, ADOBA will be more suitable for bio-energy production for the following reasons: 1) ADOBA has the same first acitogenesis step as AD, so ADOBA will provide the same benefits as AD in many aspects, including production of renewable energy, reduction of greenhouse gas (GHG) emissions, and potential pathogen reduction. 2). ADOBA will degrade organics much faster than the AD followed by microalgae culture, because without the rate-limiting methanogenesis step, the acitogenesis step of the AD will only serve as the pre-treatment of waste materials and the organic nutrients such as VFA will stimulate the fast growth rate of heterotrophic microalgae cultivation. Secondly, ADOBA-microalage process is proposed to utilize microalgae for the carbon dioxide capture. With the integration of microalgae cultivation with AD, the biogas can be relatively purified via CO2 assimilation with microalgae. Finally, taking advantage of fungal pelletization and its merit on liquid/solid separation, ADOBA-fungi process is proposed to accumulate oil via pelletized cell culture, so that fat cells can be easily harvested.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
4025370202060%
4035370202040%
Goals / Objectives
Research goals An innovative two step Anaerobic Digestion and Oil/Biomass Accumulation (ADOBA) process (Fig. 1) is proposed to integrate fermentative hydrogen production directly with either mixotrophic/autotrophic microalgae cultivation for oil accumulation (ADOBA-microalgae) or with fungal cultivation (ADOBA-fungi). The first step is the acitogenesis/hydrogen fermentation, where organic materials are degraded to produce H2/biogas and volatile fatty acid (VFA); and then in the second step, the effluent from the fermentation will be processed to culture microalgae or fungi for the oil synthesis, where the nutrients such as VFA, N and P will be utilized. Impurities of the biogas from the first stage, such as CO2, NH3 and H2S, will be able to be assimilated and cleaned via microalgae growth. The proposed ADOBA process will provide a new application of the VFA, N and P from water, an innovative method to remove impurities from biogas and a unique way to separate the cell biomass, all of which will increase the economic feasibility of the biological hydrogen production process. Objectives and expected outputs The project will be focusing on the feasibility study of the proposed process. For the ADOBA-microalage process, our primary focus is to study hydrogen gas purification via microalgae cultivation. Our hypothesis of this research is that carbon dioxide will be totally removed from the biogas without oxygen production, therefore, the biogas can be purified. The whole process will be integrated and optimized for their culture conditions. Our goal of the process is to produce around 2 mole H2 per mole glucose, completely assimilate VFA, N and P by microalgae cultivation, dramatically decrease the microalgae cultivation time, increase the oil content to 40-50%, and purify H2 produced from the system to reach 90%. In addition, for the ADOBA-fungi process, a new concept of pelletized/granulated cell cultivation will be adventured for valuable bioproducts and bioenergy production due to above merits. Application of cell aggregates to oil production depends upon obtaining uniform pellets of a desired size. This is not easily accomplished, since many factors influence pellet formation. Filamentous oleaginous fungi Aspergillus oryzae or Mortierella isabellina will be chosen as a model to test our research hypothesis: the pellet will be formed on these fungal fermentation and the pelletized culture will significantly facilitate the harvest of the cell biomass, and decrease the overall cost of the microbial oil accumulation process.
Project Methods
Step 1: Utilization of VFA by microalgae and possible inhibitions Different concentrations of VFA and alcohols will be added to the artificial culture medium to study the assimilation and possible inhibition by microalgae. Chlorella protothecoides can grow on glycerol or acetate, similar as on glucose, based on PI's previous research. The remaining list of chemicals generated from anaerobic fermentation need to be studied for the microalgae assimilation. Chlorella protothecoides may not have the capability to utilize certain chemicals and alcohols may have some inhibition effects on microalgae growth, however, anaerobic fermentation pathway can be adjusted through several fermentation factors, for example partial H2 pressure and alkalinity, to avoid producing the inhibitive products. Step 2: Biogas purification via microalgae cultivation Synthetic biogas, similar to ones produced from anaerobic fermentation, will be feeding into the microalgae cultivation. We will study the factors on how the biogas influences the microalgae growth and lipid accumulation. Generally CO2 will stimulate the autotrophic microalgae growth, but the effects of NH3 or H2S on algae growth will also be studied. This is a brand new approach and it will bring up several future research topics about the mechanism of the carbon dioxide capture in this system, how to design a closed reactor and how to collect the purified highly flammable H2 gas. Detailed engineering designs to address these issues will not be included in current research proposal, but they will be future focus. Step 3: Investigate the culture factors for fungal pellet formation We will study the influence of fermentation factors, such as pH, inoculum size, substrate concentration, inductive additives, storage time, shaking speed, and temperature on pellet formation using batch culture. Previous research has approved that fungal spores cultured at nitrogen rich culture medium can easily form pellets, especially with the inductive additions. Chitosan is also proved to be effectively inducing the pelletization of certain microorganism. Step 4: Integration of ADOBA and techno-economic analysis The primary research efforts will focus on the integration of microalgae/fungal cultivation on the effluent of anaerobic fermentation. A continuous up-flow anaerobic reactor will be set up to degrade the synthetic wastewater and the effluent will be tested to directly culture microalgae/fungi. The research will focus on following issues: 1) How to adjust operational factors of the fermentation to provide higher yield of H2 as well as a suitable culture medium for the subsequent microalgae/fungal growth. 2) Oxygen availability and CO2 mitigation mechanism; 3) Stressed conditions for higher lipid accumulation. Finally, a techno-economic assessment will be conducted by using Aspen Plus software for the whole process and it will result in a simulation model to predict the production and economic margin at different scales, and be able to conclude the optimal cultivation conditions in terms of both technical and economic aspects.

Progress 10/01/10 to 10/01/13

Outputs
Target Audience: Farmers and commodity groups, for instance, some dairy and swine farmers, MN Pork Board, IA Pork Board. Scientific community in the bioenergy related fields. Students and researchers in training. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? This project has trained the following graduate students, visiting scholars and postdoc researchers at Bo Hu’s group at University of Minnesota. Mi Yan, Jianguo Zhang, Chunjie Xia, Sarman Gultom, Yan Yang, Yulin Ye, Jing Gan, Carlos Zamalloa Nalvarte. Around 10 undergraduate students also participated in the project. How have the results been disseminated to communities of interest? Besides several manuscripts were published from our research, which are listed in the publication session, we were invited to make the following presentations to the national conferences. Larry Jacobson, P.E., Bo Hu, Mi Yan, Neslihan Akdeniz, Chuck Clanton, P.E., 2013, The Potential Causes of Manure Pit Foaming in Pig Finishing Barns, oral presentation at ASABE Annual International Meeting, Kansas City, Missouri Yulin Ye, Bo Hu, 2013, Filamentous phosphorus accumulating fungus and its application to recover phosphorus from wastewater, oral presentation at 35th Symposium on Biotechnology for Fuels and Chemicals, Portland, OR Mi Yan, Bo Hu, 2012. Revealing of Swine Manure Foaming Issue, oral presentation at ASABE Annual International Meeting, Dallas, TX Yan Yang, Bo Hu, 2012. Screening of Oleaginous Fungi from Oil Rich Plants for Biodiesel Production, oral presentation at ASABE Annual International Meeting, Dallas, TX Yulin Ye, Bo Hu, 2012. Phosphorus Accumulating Fungus and its Cultivation on Wastewater, oral presentation at ASABE Annual International Meeting, Dallas, TX Yan Yang, Bo Hu, 2012. Screening of Oleaginous Fungi from Oil-Rich Plants for Biodiesel Production, oral presentation at 34th Symposium on Biotechnology for Fuels and Chemicals, New Orleans, LA Yulin Ye, Bo Hu, 2012. Phosphorus Removal and Biological Fertilizer Production via Phosphorus Accumulating Fungus, poster presentation at 34th Symposium on Biotechnology for Fuels and Chemicals, New Orleans, LA Jianguo Zhang, Sarman Gultom, Bo Hu. Microalgae Pelletization Through Filamentous Fungal Co-Cultivation. poster presentation at 34th Symposium on Biotechnology for Fuels and Chemicals, New Orleans, LA Cristiano E. R. Reis, Jianguo Zhang, Bo Hu, 2011. Direct Biodiesel Production From Mucor Circinelloides Fungi, oral presentation at AICHE annual meeting, Minneapolis, MN Jianguo Zhang, Bo Hu, 2011. A Novel Method to Harvest Microalgae Via Fungal Pelletization, oral presentation at AICHE annual meeting, Minneapolis, MN Mi Yan, Bo Hu, Application of Caffeine for Higher Anaerobic Digestion Stability, Poster presentation at Sustainability and Sustainable Biorefineries, AICHE annual meeting, Oct 16-21 Jianguo Zhang, Bo Hu, Lipid Production From Lignocellulosic Materials Via Filamentous Fungi, Poster presentation at Sustainable Forest Bioresources Engineering, AICHE annual meeting, Oct 16-21 Chunjie Xia, Jianguo Zhang, Bo Hu, 2011. Microbial oil accumulation via pelletized cultivation of Mucor circinelloides, oral presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA Jianguo Zhang, Chunjie Xia, Bo Hu, 2011. Fungal Conversion Platform for Microbial Lipid Accumulation, oral presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA Mi Yan, Bo Hu, 2011. Screening of Oleaginous Fungal Strains from Soybean Plant, poster presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? We have developed a microbial community analysis approach to study the population distribution and functions of microorganisms within the AD system. AD is a natural fermentation process that degrades organic materials such as livestock waste, agricultural residue and municipal wastes, and generates methane as final product. The microbial community analysis tool will help us understand the mechanism of AD process and provide a better design for industrial applications. The detailed microbial analysis involves DGGE screening and identification steps. DGGE analysis is carried out by Gel electrophoresis system DGGE-2001-110 (C.B.S scientific) to screen all the samples on whether there are significant microbial community changes. After the initial screening confirms the differences between samples from different conditions, only a few representative samples are chosen for the identification step. Illumina pyrosequencing is performed on the PCR products of these samples to obtain a detailed description of microbial species on their relative abundance and composition. The microbial communities will be compared among different samples to see which one(s) is changed if environmental conditions change. We are also working on coupling a microbial electrolysis cell (MEC) to the anaerobic digestion in order to increase the biogas production as well as recover the nutrients such as phosphorus, nitrogen, and sulfur. We are applying the microbial analysis approach to study the foaming issues occurring in the deep manure pit in the Midwestern swine barns. It is an emerging issue in recent two or three years that methane gas entrapped in the foaming bubbles is causing explosions when the bubbles on the foamed pit break and the methane gas is suddenly released to the air. We have also adopted the methane potential measurement to study the anaerobic co-digestion of manure with food wastes and brown grease. For the swine manure foaming project, we developed foaming capability measurement method to determine the foaming potential of the manure samples and used this method to study the effects of different factors on inducing the manure foaming. The factors we studied include the fat and long chain fatty acids and fats, the fine solid particles, fibers, proteins etc. Our results showed that the main cause of the pit foaming is not the obsessive growth of filamentous bacteria, but the interaction of elevated concentration of long chain fatty acid on the surface of manure and the fine particles. This may indicate that the inclusion of bioethanol coproduct Distiller Grains (DDGS) as animal feed is the real reason for the pit foaming due to the poor digestion of the DDGS, but this hypothesis needs further investigations. Many microalgal and fungal species can accumulate high content of lipids as well as other materials with economical potentials. My research group is currently screening and developing new microbial species with higher lipid productivity and better capability to directly utilize lignocelluloses and other waste materials. One recent study of endophytic fungal community in the oilseed crops such as soybean, sun flower, canola, and evening primrose has discovered over 50 different fungal species that can directly utilize polysaccharide to accumulate over 20% of lipids in their cell biomass. We also developed several new cell cultivation and conversion platforms, such as pelletized fugal cell cultivation, acid pretreatment combined with simultaneous saccrification and fermentation, solid state fungal fermentation, and co-pelletized cultivation of fungi and microalgae, featuring easier cell harvest and lower operational costs, suitable to small/mid-sized rural operations. Among the oleaginous fungal strains we recently screened, one Fusarium strain was identified that can generate both cellulase and over 56% of oil in their cell biomass, which has a great potential to be applied as a Consolidated-Bioprocessing type of strain. This is the first report to show Fusarium strains with the capability to accumulate high content of oil and it will be a better strain for bioenergy production than those gene-modified strains since it is a wild strain. We have been working on the different process development to culture this strain for converting lignocellulosic biomass to fungal lipids and one invention disclosure has been filed to the UMN patent office. Other interesting strains were also found in these screening tests to have capabilities for accumulating phosphorus, which may bring the possibility to recycle the phosphorus in the wastes back to the farm land. We are currently developing processes to culture this fungus on the manure so that it can be used to recycle phosphorus. Swine manure has an imbalanced nitrogen/phosphorus ratio, which may cause phosphorus accumulation in the soil and risk the possibility of increased phosphorus run-off. A group of filamentous fungal strains were screened from soybean-root soil and can accumulate up to 6% phosphorus in the dry cell biomass. We are working to develop an integrated process to maximize the benefits of the anaerobic digestion and recover phosphorous as a value added product, plus create a more nutrient balance fertilizer from digested swine manure that will increase economic return and decrease the environmental impacts of the pork industry.

Publications

  • Type: Journal Articles Status: Submitted Year Published: 2014 Citation: Mi Yan, Gaurav Kandlika, Larry Jacobson, Chuck Clanton, Bo Hu, 2013, Lab Simulation to Determine the Factors Affecting Swine Manure Foaming, Trans of ASABE
  • Type: Journal Articles Status: Under Review Year Published: 2014 Citation: Cristiano E. R. Reis, Jianguo Zhang, Bo Hu, 2013, A study on biomass and lipid accumulation by pelletized culture of Mucor circinelloides on corn stover hydrolysate, Biomass and Bioenergy
  • Type: Journal Articles Status: Submitted Year Published: 2014 Citation: Chunjie Xia, Bo Hu, Wei Wei, 2013, Statistical Analysis of Cell Pelletization on the Cultivation of Mucor circinelloides for Microbial Lipid Accumulation
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2013 Citation: Sarman Gultom, Bo Hu, 2013, Invited Review: Fungal pelletization and its application in algae harvest, Energies
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2013 Citation: Yan Yang, Mi Yan, Bo Hu, 2013, Endophytic Fungal Strains of Soybean for Lipid Production
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Jianguo Zhang, Bo Hu, 2012, Effects of External Enzymes on the Fermentation of Soybean Hull to Lipid by Mortierella isabellina, Applied Biochemistry and Biotechnology, 168(7): 1896-1906
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Jianguo Zhang, Bo Hu, 2012, A Novel Method to Harvest Microalgae Via Co-Culture of Filamentous Fungi to Form Cell Pellets, Bioresource Technology, 114:529-535
  • Type: Journal Articles Status: Published Year Published: 2012 Citation: Jianguo Zhang, Bo Hu, 2012, Solid-State Fermentation of Mortierella isabellina for Lipid Production from Soybean Hull, Applied Biochemistry and Biotechnology, 166(4):1034-46
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Chunjie Xia, Jianguo Zhang, Weidong Zhang, Bo Hu, 2011, A New Cultivation Method for Bioenergy Production --- Cell Pelletization and Lipid Accumulation by Mucor circinelloides, Biotechnology for Biofuels, 4:15.
  • Type: Journal Articles Status: Published Year Published: 2011 Citation: Tamarys Heredia-Arroyo, Wei Wei, Roger Ruan, Bo Hu, 2011, Mixotrophic Cultivation of Chlorella vulgaris and its Potential Application for the Oil Accumulation from Non-sugar Materials, Biomass and Bioenergy, 35(5): 2245-2253
  • Type: Journal Articles Status: Published Year Published: 2010 Citation: Tamarys Heredia-Arroyo, Wei Wei, Bo Hu, 2010, Oil accumulation from waste via heterotrophic/mixotrophic Chlorella protothecoides, Applied Biochemistry and Biotechnology, 162 (7): 1978-1995
  • Type: Book Chapters Status: Published Year Published: 2014 Citation: Yan Yang, Bo Hu, April 2014, Bio-based chemicals: lipid and wax conversion and utilization, Book chapter for Advances in biorefineries, Biomass and waste supply chain exploitation, 978-0857095213 Woodhead Publishing Limited, Cambridge, UK
  • Type: Book Chapters Status: Published Year Published: 2013 Citation: Jianguo Zhang, Bo Hu, March 2013, Liquid-Liquid extraction in biorefineries, Separations and Purification Technologies in Biorefineries, ISBN: 978-0-470-97796-5, Wiley, UK
  • Type: Book Chapters Status: Published Year Published: 2012 Citation: Mi Yan, Jianguo Zhang, Bo Hu, December 2012, Integration of microalgae cultivation with anaerobic digestion, Book chapter for Microbial Biotechnology: Energy and Environment, ISBN 978-184-593-956-4, CABI, Page 190-206.
  • Type: Book Chapters Status: Published Year Published: 2011 Citation: Jianguo Zhang, Bo Hu, Microbial Biodiesel Production --- Oil Feedstocks Produced from Microbial Cell Cultivations. Book chapter for Biodiesel - Feedstocks and Processing Technologies, ISBN 978-953-307-713-0, InTech, November 2011, Page 93-110.


Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Currently working on two different objectives for the project: 1) study anaerobic digestion (AD) and its microbial community; 2) study new methods to culture fungi and microalgae for oil accumulation using different waste materials. Objective 1: Microbial community analysis of AD and its application. We have developed a microbial community analysis approach to study the population distribution and functions of microorganisms within the AD system. AD is a natural fermentation process that degrades organic materials such as livestock waste, agricultural residue and municipal wastes, and generates methane as final product. The microbial community analysis tool will help us understand the mechanism of AD process and provide a better design for industrial applications. The detailed microbial analysis involves DGGE screening and identification steps. DGGE analysis is carried out by Gel electrophoresis system DGGE-2001-110 (C.B.S scientific) to screen all the samples on whether there are significant microbial community changes. After the initial screening confirms the differences between samples from different conditions, only a few representative samples are chosen for the identification step. Illumina pyrosequencing is performed on the PCR products of these samples to obtain a detailed description of microbial species on their relative abundance and composition. The microbial communities will be compared among different samples to see which change if environmental conditions change. Objective 2: Fungal cultivation to accumulate oil for biodiesel production Many microalgal and fungal species can accumulate high content of lipids as well as other materials with economical potentials. My research group is currently screening and developing new microbial species with higher lipid productivity and better capability to directly utilize lignocelluloses and other waste materials. One recent study of endophytic fungal community in the oilseed crops such as soybean, sun flower, canola, and evening primrose has discovered over 50 different fungal species that can directly utilize polysaccharide to accumulate over 20% of lipids in their cell biomass. We also developed several new cell cultivation and conversion platforms, such as pelletized fugal cell cultivation, acid pretreatment combined with simultaneous saccrification and fermentation, and solid state fermentation, featuring easier cell harvest and lower operational costs, suitable to small/mid-sized rural operations. Oral presentations at national conferences in 2012: Revealing of Swine Manure Foaming Issue,ASABE Annual Intl. Meeting, Dallas,TX. Screening of Oleaginous Fungi from Oil Rich Plants for Biodiesel Production,ASABE Annual International Meeting, Dallas,TX. Phosphorus Accumulating Fungus and its Cultivation on Wastewater,ASABE Annual Intl. Meeting, Dallas, TX. Screening of Oleaginous Fungi from Oil-Rich Plants for Biodiesel Production,34th Symposium on Biotechnology for Fuels and Chemicals, New Orleans,LA. Poster presentation: Phosphorus Removal and Biological Fertilizer Production via Phosphorus Accumulating Fungus,34th Symposium on Biotechnology for Fuels and Chemicals, New Orleans,LA. PARTICIPANTS: My research group is working on this project, including the following members: Jianguo Zhang, postdoc researcher; Mi Yan, PhD student; Yan Yang, PhD student; Yulin Ye, Master student; Sarman Gultom, Master student. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Outcomes / Impacts We are applying the microbial analysis approach to study the foaming issues occurring in the deep manure pit in the Midwestern swine barns. It is an emerging issue in recent two or three years that methane gas entrapped in the foaming bubbles is causing explosions when the bubbles on the foamed pit break and the methane gas is suddenly released to the air. Our results showed that the main cause of the pit foaming is not the obsessive growth of filamentous bacteria, but the elevated concentration of long chain fatty acid on the surface of manure. This may indicate that the inclusion of bioethanol coproduct Distiller Grains (DDGS) as animal feed is the real reason for the pit foaming due to the poor digestion of oil in the DDGS, but this hypothesis needs further investigations. Among the oleaginous fungal strains we recently screened, one Fusarium strain was identified that can generate both cellulase and over 56% of oil in their cell biomass, which has a great potential to be applied as a Consolidated-Bioprocessing type of strain. This is the first report to show Fusarium strains with the capability to accumulate high content of oil and it will be a better strain for bioenergy production than those gene-modified strains since it is a wild strain. Other interesting strains were also found in these screening tests to have capabilities for accumulating phosphorus, which may bring the possibility to recycle the phosphorus in the wastes back to the farm land.

Publications

  • Yan Yang, Bo Hu, 2012. Bio-based chemicals: lipid and wax conversion and utilization, Book chapter for Advances in biorefineries, Biomass and waste supply chain exploitation, Woodhead Publishing Limited, Cambridge, UK (Submitted)
  • Jianguo Zhang, Bo Hu. March 2013. Liquid-Liquid extraction in biorefineries, Separations and Purification Technologies in Biorefineries, ISBN: 978-0-470-97796-5, Wiley, UK
  • Yan Mi, Jianguo Zhang, Bo Hu. December 2012, Integration of microalgae cultivation with anaerobic digestion, Book chapter for Microbial Biotechnology: Energy and Environment, ISBN 978-184-593-956-4, CABI.
  • Yan Yang, Mi Yan, Bo Hu, 2012. Endophytic Fungi Screened from Soybean for Lipids Production (Submitted)
  • Jianguo Zhang, Bo Hu, 2012. Effects of External Enzymes on the Fermentation of Soybean Hull to Lipid by Mortierella isabellina, Applied Biochemistry and Biotechnology (Accepted)
  • Jianguo Zhang, Bo Hu, 2012. A Novel Method to Harvest Microalgae Via Co-Culture of Filamentous Fungi to Form Cell Pellets, Bioresource Technology, 114:529-535
  • Jianguo Zhang, Bo Hu, 2012. Solid-State Fermentation of Mortierella isabellina for Lipid Production from Soybean Hull, Applied Biochemistry and Biotechnology, 166(4):1034-1046


Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: We are currently working on two different objectives within this project: 1) study the anaerobic digestion (AD) and its microbial community; 2) study the new methods to culture fungi and microalgae for oil accumulation from using different waste materials. Objective 1) Microbial community analysis of AD and its application. AD is an industrial process to degrade organic matter by natural anaerobic fermentation and generate methane as the main product, which is flammable. Different groups of microorganisms are working together as a food chain in AD and the outcome of the overall microbial communities is unique for each different condition although they are generally balanced. We are developing and adopting a microbial analysis approach to be applied in the AD in order to understand the microbial community function and apply these knowledge to facilitate the operation of AD. The detailed microbial analysis involves DGGE screening and identification steps. DGGE analysis is carried out by Gel electrophoresis system DGGE-2001-110 (C.B.S scientific) to screen all the samples on whether there are significant microbial community changes. After the initial screening confirms the differences between samples from different conditions, only a few representative samples are chosen for the identification step. 454 pyrosequencing is performed on the PCR products of these samples to obtain a detailed description of microbial species on their relative abundance and composition. The microbial communities will be compared among different samples to see which one(s) is changed if environmental conditions change. Objective 2: Fungal cultivation to accumulate oil for biodiesel production Many microalgal and fungal species can accumulate high content of lipids via heterotrophic growth as long as organic carbon source such as sugar is provided. My research group is currently screening and developing new microbial species with higher lipid productivity and better capability to directly utilize lignocelluloses and other waste materials. One recent study of endophytic fungal community in the soybean crops has discovered 13 different fungal species that can directly utilize polysaccharide to accumulate over 20% of lipids in their cell biomass. We also developed several new cell cultivation and conversion platforms, such as pelletized fugal cell cultivation, acid pretreatment combined with simultaneous saccrification and fermentation, and solid state fermentation, featuring easier cell harvest and lower operational costs, suitable to small/mid-sized rural operations. We also studied to the new cultivation method to culture microalgae for the oil accumulation and one patent application has recently filed to co-culture microalgae with certain filamentous fungi so that the microalgae cells can be pelletized during the cell cultivation. The pelletization of microalgae cells not only facilitates easier cell harvest, but also removes the mutual shading effect, resulting to significantly higher microalgae cell productivity. PARTICIPANTS: PI: Bo Hu, Jianguo Zhang (postdoc researcher), Mi Yan(graduate student), Chunjie Xia(research specialist), Cristiano Reis (undergraduate student) TARGET AUDIENCES: Biofuel industry, swine farmers in Midwest PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
We are applying the microbial analysis approach to study the foaming issues occurring in the deep manure pit in the Midwestern swine barns. It is an emerging issue in recent two or three years that methane gas entrapped in the foaming bubbles is causing explosions when the bubbles on the foamed pit break and the methane gas is suddenly released to the air. Filamentous bacteria are hypothesized to grow on the manure pit, and are causing the explosive gas entrapped inside foam. During recent sampling and analysis, we found that major microbial difference occurs between the foam layer and the liquid manure; and there are no major differences between non-foaming manure and foaming liquid manure. So any comparison between manure compositions should also emphasize the differences between foam layer and liquid foaming manure. We also found out that N. limicola I, a filamentous bacterium species widely reported as one of the filamentous bacteria causing bulking and foaming issues in the industrial wastewater treatment process, was massively growing in the foam layer; therefore, this bacteria should be responsible to the foaming of pig manure. We are currently working on identification of risk factors to stimulate the bacteria growth and root cause of this safety hazard. Besides several manuscripts and patent were published from our research, which are listed in the publication session, we were invited to make the following presentations to the national conferences. Cristiano E. R. Reis, Jianguo Zhang, Bo Hu, 2011. Direct Biodiesel Production From Mucor Circinelloides Fungi, oral presentation at AICHE annual meeting, Minneapolis, MN Jianguo Zhang, Bo Hu, 2011. A Novel Method to Harvest Microalgae Via Fungal Pelletization, oral presentation at AICHE annual meeting, Minneapolis, MN Mi Yan, Bo Hu, Application of Caffeine for Higher Anaerobic Digestion Stability, Poster presentation at Sustainability and Sustainable Biorefineries, AICHE annual meeting, Oct 16-21 Jianguo Zhang, Bo Hu, Lipid Production From Lignocellulosic Materials Via Filamentous Fungi, Poster presentation at Sustainable Forest Bioresources Engineering, AICHE annual meeting, Oct 16-21 Chunjie Xia, Jianguo Zhang, Bo Hu, 2011. Microbial oil accumulation via pelletized cultivation of Mucor circinelloides, oral presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA Jianguo Zhang, Chunjie Xia, Bo Hu, 2011. Fungal Conversion Platform for Microbial Lipid Accumulation, oral presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA Mi Yan, Bo Hu, 2011. Screening of Oleaginous Fungal Strains from Soybean Plant, poster presentation at 33rd Symposium on Biotechnology for Fuels and Chemicals, Seattle, WA

Publications

  • Jianguo Zhang, Bo Hu, 2011, A Novel Method to Harvest Microalgae Via Co-Culture of Filamentous Fungi to Form Cell Pellets, Bioresource Technology (Accepted with revision)
  • Jianguo Zhang, Bo Hu, 2011, Solid-State Fermentation of Mortierella isabellina for Lipid Production from Soybean Hull, Applied Biochemistry and Biotechnology (Accepted)
  • Jianguo Zhang, Bo Hu, Microbial Biodiesel Production --- Oil Feedstocks Produced from Microbial Cell Cultivations. Book chapter for Biodiesel - Feedstocks and Processing Technologies, ISBN 978-953-307-713-0, InTech, November 2011, Page 93-110.
  • Bo Hu, Jianguo Zhang, New method to harvest microaglae via cell pelletizatioin assisted with filamentous fungi, 2011, US Patent Application No. 61/547,177.
  • Chunjie Xia, Jianguo Zhang, Weidong Zhang, Bo Hu, 2011, A New Cultivation Method for Bioenergy Production --- Cell Pelletization and Lipid Accumulation by Mucor circinelloides, Biotechnology for Biofuels, 4:15.
  • Tamarys Heredia-Arroyo, Wei Wei, Roger Ruan, Bo Hu, 2011, Mixotrophic Cultivation of Chlorella vulgaris and its Potential Application for the Oil Accumulation from Non-sugar Materials, Biomass and Bioenergy, 35(5): 2245-2253