The number of patent publications from the first half of 2011 indicates that research on starter material fermentation and “fermenters” is increasing. As a matter of fact, there have been more patent publications on this area of biofuel production in the first half of 2011 than for the entire year of 2010. This article is the second part of a two-part feature; the first part appeared in the October issue of Industrial Biotechnology (2011;7(5):354–356). The first article reviewed several fermentation-related patent publications from the summer of 2011. Specifically, it focused on the following topics: enzymatic modification and enzyme systems; process efficiency; and microorganism biofilms or membranes. This article presents historical trends in two of these categories—process efficiency and enzymatic modification and enzyme systems—and covers some of the more significant patent applications over the last 3 to 5 years. It also provides a roadmap for how the research reached this point.
Process Efficiency
One of the first US Patents to go beyond basic fermentation of raw materials to produce a biofuel is US Patent 4908373, 1-[2-(4-Hydroxybenzoyl)ethanoyl]-2-piperidone and a process for production as well as alcohol fermentation promoter containing the same as effective ingredient
(inventor: Okumura, Minoru et al.; Taki Chemical Co., Ltd; March 13, 1990). The inventors disclose in the background that research had been directed to a review of raw materials and a review of yeast cells, but not in the process efficiency of biofuel production. They then disclose that 1-[2-(4-hydroxybenzoyl)ethanoyl]-2-piperidone works to promote fermentation economically with raw materials, including inexpensive and/or starchy raw materials. The inventors state that they came across this compound based on their work with physiologically active substances, specifically N-acyl lactam compounds.
US Patent 6454944, Process and apparatus for conversion of biodegradable organic materials into product gas
(inventor: Larry J. Raven, Larry J.; September 24, 2002) discloses “anaerobic digesters” and an appropriate system/apparatus that are able to achieve effective conversion of slurries of biodegradable solids. Unlike previous applications in this field that are limited to primarily liquid feedstocks, the inventor claims that the anaerobic materials can effectively digest slurries that contain at least 10 percent biodegradable solids and up to 100 percent of biodegradable solids. As outlined in this patent, pure sugar, beet molasses, starches, high sugars, beet sugar, sugar beet derivatives, flours, pulps, and other materials are able to be effectively processed using anaerobic digesters. The inventor also states that a small amount of liquid waste will be generated by the process and “98 to 100 percent of its feedstock” is converted into product gas. One reason for such a high conversion rate into biogas/biofuel is that there is an unlimited retention time for the feedstock/digester mixture.
US Patent 7704723,
Isolation and characterization of novel Clostridial species
(inventors: Raymond L. Huhnke, assignee: The Board of Regents for Oklahoma State University and The Board of Regents of the University of Oklahoma; April 27, 2010) discloses the use of “indirect fermentation” or gasification fermentation to convert waste gases into biofuel. In these embodiments, bacteria actively participate in this conversion during indirect fermentation. The bacteria being used by the inventors in this patent are “extremely stable” and “can be stored at room temperature or in a 38°C incubator for over one year while retaining activity.” The inventors disclose the isolation of these species, and they also discuss the systems and processes in which these bacteria can be used.
Author's Note: In general, when patents and patent applications are reviewed, it is instructive to keep a few points in mind. There are two types of published patent applications – those that have issued and those that have published but are still pending and under examination. This article will primarily focus on patent publications, since those documents are indicative of more recent research and development of biofuels. In fact, the patent applications being published in December of 2011 were first filed in June of 2010.
An issued patent has a fixed set of claims at the end of that patent that define the invention regardless of what is included in the detailed description section. Anyone reviewing issued patents for an indication of the actual invention should turn to the claims section first. The detailed description section should primarily be used to provide context of the claims and/or definitions of some of the terms/phrases in the claims. Issued patents are in force 20 years from the filing date, and they give the patent owner the right to exclude others from making, using and/or selling the claimed invention in the country where the patent issued.
Published patent applications are useful to provide notice to the general public and/or competitors as to potential future patents and their scope. Between the filing date or priority date of the application and the publication date, the patent application is not published, and therefore, not readily available to the public for review.
Inventors use pending patent publications to put likely competitors on notice that they may have enforceable patent rights at some point in the future. Competitors use patent publications to scope out the technology landscape. It is important to note, however, that the existence of a patent publication does not necessarily mean that a patent will issue from that application or that the final issued set of claims will be the same or resemble the claims in the publication. These publications should primarily be used for notice and information purposes.
US Patent 7831318, Model predictive control of fermentation temperature in biofuel production
(inventor: James F. Bartee; assignee: Rockwell Automation Technologies, Inc.; November 9, 2010) discloses systems and methods of “controlling temperature of a batch fermenter in a biofuel production process” using a nonlinear predictive integrating temperature model that incorporates information regarding fermenter level. This model, combined with process information, facilitates the identification of target values for manipulated process variables in order to optimize the batch biofuel yield.
US Patent 7862992,
Dynamic fermentation controller
(inventors: Ganti S. Murthy, et al.; assignee: The Board of Trustees of the University of Illinois; January 4, 2011) is another process and model development-related patent. This patent discloses the determination of set point values for a dynamic fermentation controller where the values may be temperature, pH, and/or enzyme dosage for a fermentation system. Specifically, independent claim 1 recites the method for production of ethanol based on the development of the predictive model: “a method for the production of ethanol comprising: receiving a temperature of a simultaneous saccharification and fermentation system; receiving a pH of the simultaneous saccharification and fermentation system; receiving information identifying amounts of components of a fermented mash generated by the simultaneous saccharification and fermentation system; generating, based at least in part on the temperature, the pH, and the information identifying amounts of components of the fermented mash, values for temperature, pH, and enzyme dosage for the simultaneous saccharification and fermentation system; and outputting the values to one or more controllers of the simultaneous saccharification and fermentation system wherein the generating and outputting values are based at least in part on a saccharification model that predicts concentrations of fermented mash or a fermentation model that predicts yeast metabolism, the one or more controllers allowing for the production of ethanol.”
Enzymatic Modification and Enzyme Systems
US Patent 6566107,
Recombinant
Zymomonas mobilis with improved xylose utilization
(inventor: Min Zhang; assignee: Midwest Research Institute; May 20, 2003) discloses a strain assignee or derivative of Zymomonas mobilis ATCC31821 that can produce ethanol as a fermentation product of a carbohydrate medium that contains xylose. According to the patent, cellulosic biomass is an attractive ethanol feedstock because it is readily available and relatively inexpensive. However, it can be difficult to obtain high yields of ethanol from fermentation because of the hurdles associated with the conversion of xylose. The inventor states that the particular strain/derivative of recombinant Zymomonas mobilis provides “enhanced xylose utilization and enhanced ethanol process yield.” The inventor also states that the cost of ethanol production from agricultural and cellulosic biomass feedstocks is significantly decreased by using the inventive strains/derivatives claims therein. Finally, the inventor explains that previous problems using Zymomonas mobilis are mitigated by ensuring that exogenous genes encoding “xylose isomerase, xylulokinase, transaldolase and transketolase…are fused to at least one promoter recognized by Zymomonas which regulates the expression of at least one of said genes.”
US Patent 6737257, Hyperthermophilic enzymes for industrial chemical redox reactions: a method for biofuel ethanol production
(inventor: Paul Blum; assignee: Board of Regents of the University of Nebraska; May 18, 2004) discloses the use of hyperthermophilic enzymes for ethanol production processes. Independent claim 1 of this patent states: “A method for coupled synthesis and recovery of alcohol at or above a temperature of about 65°C comprising: coupled enzymatic oxidation-reduction of substrate, removal of product by volatilization, and regeneration of pyridine nucleotides, wherein the oxidoreductase enzymes are from hyperthermophilic Archaea.” The inventor states that many attempts to improve ethanol recovery from processes that use enzymes at the time this patent application was filed failed because the fermentation technology resulted in an environment that was toxic for microbial populations. In these contemplated embodiments, the claimed enzyme populations allow for the generation of alcohol at higher temperatures, which allows for improved alcohol volatilization and improved alcohol recovery.
A group of US patents assigned to Novozymes, Inc. discloses various polypeptides that have enzymatic activity, especially when they act synergistically with other contemplated enzymes, and are capable of efficiently converting cellulose into ethanol. These include: US Patents 7033811, Polypeptides having xyloglucanase activity and nucleic acids encoding same; 7172891, Polypeptides having xyloglucanase activity and nucleic acids encoding same; 7220565, Polypeptides having cellobiohydrolase activity and polynucleotides encoding same; 7244605, Polypeptides having beta-glucosidase activity and polynucleotides encoding same; 7348168, Polypeptides having cellobiohydrolase II activity and polynucleotides encoding same; and 7670819, Polynucleotides encoding polypeptides having beta-glucosidase activity
. It should be noted that the inventors disclose other uses for these polypeptides other than biomass-to-ethanol production.
US Patent 7364890, Thermal tolerant avicelase from Acidothermus celluloyticus
(inventors: Shi-You Ding, et al.; assignee: Midwest Research Institute; April 29, 2008), US Patent 7393673 Thermal tolerant exoglucanase from Acidothermus cellulolyticus
(inventors: William S. Adney, et al.; assignee: Midwest Research Institute; July 1, 2008), and US Patent 7538200,
Thermal tolerant avicelase from Acidothermus celluloyticus
(inventors: Shi-You Ding, Shi-You, et al.; assignee: Alliance for Sustainable Energy, LLC; May 26, 2009) are additional patents from Midwest Research/Alliance that disclose a thermally tolerant/thermostable enzyme that can be used to convert biomass into biofuel. The inventors identify three main areas of expenditures for ethanol production: a) pretreatment costs; b) fermentation costs; and c) other costs. These particular embodiments in this patent address pretreatment, in that the enzymes are more effective than conventionally used enzymes and, therefore, result in a reduced need for pretreatment and fermentation, and that the enzymes are more effective and stable during the fermentation process, thereby producing increased amounts of ethanol.
US Patent 7682811, Systems and methods for producing biofuels and related materials
(inventors: Susan Leschine, et al.; assignee University of Massachusetts; March 23, 2010) discloses the use of Clostridium phytofermentans cells and strains of the species to convert biomass into ethanol. The inventors state that this species is effective in large scale conversions of biomass, such as high molecular weight carbohydrates, into ethanol.
US Patent 7883872, Construction of highly efficient cellulase compositions for enzymatic hydrolysis of cellulose
(inventors: Alexander V. Gusakov, et al.; assignee: Dyadic International (USA), Inc.; February 8, 2011) discloses new enzyme compositions that, according to the inventors, are effective in hydrolysis of lignocellulosic biomass. These compositions include enzymes derived from Chrysosporium lucknowense, along with other enzymes, such as CBH Ia and IIb, both of which have a cellulose-binding module.
Similarly, a recombinant microorganism figures prominently in US Patent 7910342,
Fermentive production of isobutanol using highly active ketol-acid reductoisomerase enzymes
(inventors: Der-Ing Liao, et al.; assignee: Butamax Advanced Biofuels LLC; March 22, 2011) discloses the use of ketol-acid reductoisomerase enzyme, together with other enzymes in some cases, to convert glucose to isobutanol. These enzymes and enzyme combinations are used to boost production of isobutanol from normally very low yields.
A review of patents related generally to fermentation of starter materials shows that this area of research is escalating and continues to be a hot topic for development of large scale and/or commercial processes. In many instances, this research is directed to modifying or blending conventional enzymes to boost production efficiency and yield. In addition, process parameters and models are in development that will improve process efficiency and product yield using conventional fermentation materials. These two main areas of research–process efficiency and enzymatic modification/systems–are certainly not on the decline and, if issued patents and patent filings are any indication, they will continue to grow in importance.
