Patents by Inventor Willem Heber van Zyl
Willem Heber van Zyl has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20230183721Abstract: A method of producing a modified Saccharomyces cerevisiae yeast strain with enhanced resistance (or tolerance) to pretreatment-derived microbial inhibitors such as furans, phenolics and weak acids is provided, which comprises integrating at least one copy of the TAL1 gene and at least one copy of two or more of the FDH1, AR11 and ADH6 genes into the S. cerevisiae genome. A modified yeast strain so obtained is also provided, the modified yeast strain being capable of simultaneously overexpressing these genes relative to a yeast strain which hasn't been modified in the same manner. S. cerevisiae strains which have been modified as described herein can be used to ferment lignocellulosic hydrolysates containing pretreatment inhibitors such as furans, phenolics and weak acids. Suitable lignocellulosic hydrolysates include sugarcane bagasse (SCB) and waste streams from the pulp and paper industry, such as spent sulphite liquor (SSL).Type: ApplicationFiled: May 5, 2021Publication date: June 15, 2023Inventors: BIANCA ANINA BRANDT, JOHANN FERDINAND GÖRGENS, WILLEM HEBER VAN ZYL
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Patent number: 10253337Abstract: A recombinant yeast that expresses both an ?-amylase (SEQ ID NO: 1) and a glucoamylase (SEQ ID NO: 2) from Talaromyces emersonii (recently re-named as Rasamsonia emersonii) is provided. The use of the recombinant yeast in a process for producing an alcohol, in particular a biofuel, from starch or sugars is also described.Type: GrantFiled: December 4, 2017Date of Patent: April 9, 2019Assignee: Stellenbosch UniversityInventors: Rosemary Anne Cripwell, Willem Heber Van Zyl, Shaunita Hellouise Rose
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Publication number: 20180155744Abstract: A recombinant yeast that expresses both an ?-amylase (SEQ ID NO: 1) and a glucoamylase (SEQ ID NO: 2) from Talaromyces emersonii (recently re-named as Rasamsonia emersonii) is provided. The use of the recombinant yeast in a process for producing an alcohol, in particular a biofuel, from starch or sugars is also described.Type: ApplicationFiled: December 4, 2017Publication date: June 7, 2018Applicant: Stellenbosch UniversityInventors: Rosemary Anne Cripwell, Willem Heber Van Zyl, Shaunita Hellouise Rose
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Publication number: 20170145374Abstract: The invention provides a method and system for controlling the conversion of crystalline insoluble cellulose to an organic product in a bioreactor containing crystalline insoluble cellulose and a culture medium. A processor of a computing device receives an input from a sensor in the bioreactor. The input may be a measurement of one or more of concentration, temperature, pH and pressure. The processor calculates conversion of cellulose using the input to provide a total calculated organic product in the bioreactor. The processor receives a further input from a sensor in the bioreactor of the total actual organic product and compares the total calculated organic product and the total actual organic product. The processor then transmits an instruction to an agitator associated with the bioreactor to control agitation of the content of the bioreactor if the total actual organic product is outside a predetermined range of the total calculated organic product.Type: ApplicationFiled: February 1, 2017Publication date: May 25, 2017Inventors: Willem Heber Van Zyl, Josebus Maree Van Zyl, Thomas Michael Harms, Eugene Van Rensburg, Lee Rybick Lynd
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Patent number: 9243256Abstract: The invention relates to the combination of the TLG1 glucoamylase from Thermomyces lanuginoses with: (i) the SFA1 alpha-amylase from Saccharomycopsis fibuligera; and/or (ii) the LKA alpha-amylase. The enzyme combinations may be expressed in a host cell (e.g. in Saccharomyces cerevisiae) or provided as an enzyme composition. Methods for making the enzyme combinations of the invention are provided. The invention also relates to a yeast strain which exhibits amylolytic activity and promising fermentative abilities. Processes for producing a fermentation product (in particular alcohol) from starch-containing material are described.Type: GrantFiled: April 12, 2010Date of Patent: January 26, 2016Assignees: Stellenbosch University, Universita Degli Studi Di PadovaInventors: Willem Heber Van Zyl, Tania Jooste, Johann Ferdinand Gorgens, Maryna Saayman, Lorenzo Favaro, Marina Basaglia, Sergio Casella
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Publication number: 20130244295Abstract: The invention relates to the combination of the TLG1 glucoamylase from Thermomyces lanuginoses with: (i) the SFA1 alpha-amylase from Saccharomycopsis fibuligera; and/or (ii) the LKA alpha-amylase. The enzyme combinations may be expressed in a host cell (e.g. in Saccharomyces cerevisiae) or provided as an enzyme composition. Methods for making the enzyme combinations of the invention are provided. The invention also relates to a yeast strain which exhibits amylolytic activity and promising fermentative abilities. Processes for producing a fermentation product (in particular alcohol) from starch-containing material are described.Type: ApplicationFiled: April 12, 2010Publication date: September 19, 2013Applicants: Universita Degli Studi Di Padova, Stellenbosch UniversityInventors: Willem Heber Van Zyl, Tania Jooste, Johann Ferdinand Gorgens, Maryna Saayman, Lorenzo Favaro, Marina Basaglia, Sergio Casella
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Publication number: 20130233501Abstract: The invention provides a method of modifying soluble xylan which contains glucuronic acid and/or arabinose side chains so that it can be adsorbed onto other substrates. The method includes the steps of enzymatically modifying the xylan by selectively removing glucuronic acid and/or arabinose side chains from the xylan with ?-D-glucuronidase and/or ?-L-arabinofuranosidase, and allowing the modified xylan to adsorb onto the substrate. The substrate may be a cellulosic substrate like pulp or paper or a non-cellulosic substrate. The enzymes are able to remove a sufficient number of the xylan side chains so as to decrease water solubility of the xylan, induce xylan precipitation and allow adsorption of the xylan onto other substrates. A pulping process which incorporates modification of xylan and adsorption onto cellulosic material is also provided, as are products which contain the modified xylan.Type: ApplicationFiled: June 7, 2011Publication date: September 12, 2013Applicant: STELLENBOSCH UNIVERSITYInventors: Willem Heber Van Zyl, Annie Fabian Abel Chimphango, Johann Ferdinand Gorgens
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Publication number: 20130185037Abstract: A system for modelling the conversion of crystalline insoluble cellulose to ethanol is provided which includes a processor configured to calculate the production rate for ethanol based on a number of inputs and as a function of specific equations. The system can form part of a control system for controlling the operation of a plant which produces ethanol from cellulose.Type: ApplicationFiled: July 8, 2011Publication date: July 18, 2013Applicant: STELLENBOSCH UNIVERSITYInventors: Willem Heber Van Zyl, Josebus Maree Van Zyl, Thomas Michael Harms, Engene Van Rensburg, Lee Rybeck Lynd
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Publication number: 20130089592Abstract: The invention provides a method of enzymatically modifying xylan by selectively removing glucuronic acid and/or arabinose side chains from the xylan with a-D-glucuronidase and/or a-L-arabinofuranosidase, and allowing the modified xylan to form into a hydrogel when the xylan becomes insoluble. A bioactive substance, such as a protein, enzyme, antimicrobial agent, bactericide or pharmaceutical compound can be added to the xylan so that the substance is encapsulated within the hydrogel or incorporated onto its surface. The hydrogel can be used as a drug delivery agent, such as for sustained-release or targeted drug delivery, rectal drug delivery or a dressing for a wound, burn or scar. The hydrogel can also be used as a coating, such as on medical gloves, catheters, surgical drainage systems, utensils or the like, or can be used in a scaffold for tissue engineering.Type: ApplicationFiled: June 7, 2011Publication date: April 11, 2013Applicant: STELLENBOSCH UNIVERSITYInventors: Willem Heber Van Zyl, Annie Fabian Abel Chimphango, Johann Ferdinand Gorgens
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Publication number: 20110177542Abstract: The present invention relates to methods for improving a host cell's ability to utilize the disaccharide cellobiose. In some embodiments, a transformed cell expresses intracellular ?-glucosidase. In other embodiments, a transformed host cell is able to grow on media wherein cellobiose is the sole carbon source. In other embodiments, selection methods are provided which improve a host cell's ability to grow on cellobiose-containing media.Type: ApplicationFiled: May 9, 2008Publication date: July 21, 2011Applicant: Stellenbosch UniversityInventors: Willem Heber Van zyl, Ronel Van Rooyen, Shaunita Hellouise Rose
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Publication number: 20110129888Abstract: The present invention is directed to host cells capable of fermenting cellulosic materials for the production of ethanol. Microorganisms engineered to be able to use amorphous cellulosic materials in a fermentation process to produce ethanol are disclosed. Additionally, methods of using the host organisms of the invention and compositions for producing ethanol according to the invention are disclosed.Type: ApplicationFiled: September 14, 2007Publication date: June 2, 2011Applicant: Stellenbosch UniversityInventors: Willem Heber Van Zyl, Riaan Den Haan
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Publication number: 20090004331Abstract: The invention provides a process of treating Rooibos plant material to obtain Rooibos tea extracts with improved extract yield and colour development. The process includes contacting Rooibos plant material with an effective amount of at least one exogenous enzyme under predetermined conditions thereby to obtain Rooibos tea extracts having improved extract yield and colour development. The enzyme is selected from pectinase, ferulic acid esterase, ?-glucanase, cellobiohydrolase, ?-xylanase and phenol oxidase and the Rooibos plant material is selected from green tea, fermented tea or spent tea.Type: ApplicationFiled: July 25, 2005Publication date: January 1, 2009Inventors: Marinda Bloom, Willem Heber Van Zyl, Elizabeth Joubert, Alfred Botha, Dawie De Villiers
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Publication number: 20030157675Abstract: The present invention relates to a method for obtaining a recombinant yeast of Saccharomyces cerevisiae, which ferments lignocellulose raw materials to ethanol, including introducing DNA into a yeast so as to cause the yeast to have introduced genes encoding xylose reductase, xylitol dehydrogenase and xylulokinase.Type: ApplicationFiled: November 14, 2002Publication date: August 21, 2003Inventors: Ricardo Roman Cordero Otero, Barbel Hahn-Hagerdal, Willem Heber Van Zyl
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Patent number: 6475768Abstract: The present invention relates to novel nucleic acid sequences which, upon expression in a procaryotic or eucaryotic cell, code for a polypeptide having an elevated specific xylose isomerase activity compared to the wildtype Thermus thermophilus xylose isomerase. They are selected from a) nucleic acid sequences shown in SEQ. ID. No 1; b) the complementary strand of the sequence defined in (a) above; c) nucleic acid sequences which hybridize to the sequences defined in (a) or (b) above; d) nucleic acid sequences which, but for the degeneracy of the genetic code, would hybridize to the sequences defined in (a), (b) or (c) above and which code for the same polypeptide as those defined in (a), (b) or (c) above. The present invention further provides a process of producing ethanol from xylose containing materials comprising contacting cells that express such nucleic acid sequences and novel modified xylose isomerases that advantageously can be applied in the production of fructose syrups.Type: GrantFiled: April 7, 2000Date of Patent: November 5, 2002Assignee: Forskarpatent I Syd ABInventors: Ricardo Román Cordero Otero, Márk Gárdonyi, Bärbel Hahn-Hägerdal, Willem Heber van Zyl, Eva Anna Viktoria Dackehag