Jian Yu

US Patent:

7141400, Nov 28, 2006

Filed:

Jan 15, 2003

Appl. No.:

10/501052

Inventors:

Jian Yu - Honolulu HI, US

Assignee:

University of Hawaii - Honolulu HI

International Classification:

C12P 7/62
C12P 39/00

US Classification:

435135, 42 42

Abstract:

A system and method for converting organic wastes to biodegradable thermoplastic materials including polyhydroxyalkanoates is disclosed, which method includes treating the organic wastes with an acidogenic microbial population to form fermentative organic acids, and polymerization of the organic acids by PHA-producing microbial species to form PHAs. The system includes a first compartment for acidogenesis of organic wastes without oxygen, and a second compartment, for polymer synthesis by enriched cultures of species with oxygen such as , or mixtures thereof. The compartments are integrated with barriers that permit mass transfer of organic acids while maintaining different culture conditions in the compartments.

US Patent:

7514525, Apr 7, 2009

Filed:

Mar 9, 2007

Appl. No.:

11/684110

Inventors:

Jian Yu - Honolulu HI, US

Assignee:

University of Hawaii - Honolulu HI

International Classification:

C08G 64/00
C08G 63/02

US Classification:

528272, 424489, 525437, 528271

Abstract:

The present invention relates to a method to recover, purify and isolate polyhydroxyalkanoate (PHA) biopolymers from PHA-containing cell mass, which includes: (a) solubilizing the non-PHA cell mass in an acidic solution, leaving a suspension of partially crystallized PHA granules; (b) adjusting the pH of the suspension to 7-11 and separating the PHA solids from the dissolved non-PHA cellular mass; (c) re-suspending the PHA solids in a bleaching solution for decolorization; and (d) drying the resulting PHA solids. About 95% or greater of original PHA in cell mass is recovered, and the purity of PHA solids is about 97% or above. The weight average molecular mass of the purified biopolyesters is about 500 kDa or greater.

US Patent:

20120252081, Oct 4, 2012

Filed:

Oct 16, 2009

Appl. No.:

13/502323

Inventors:

Jian Yu - Honolulu HI, US

Assignee:

BIO ON S.R.L. - San Giorgio Di Piano (Bologna)

International Classification:

C12P 7/62

US Classification:

435135

Abstract:

The present invention relates to a process for producing biodegradable polymeric materials including polyhydroxyalkanoates (PHAs) by using the cell debris left from PHA recovery and purification. The process comprises: (a) cultivating PHA-producing microbial cells in a medium solution containing an organic carbon source to form PHAs that are accumulated in the cells as inclusion bodies; (b) harvesting the cells from the spent medium and solubilizing the non-PHA cell mass to obtain a PHA solid and a cell debris solution; (c) separating the PHA solid from the cell debris solution; (d) feeding the cell debris solution to the cultivation step (a). By reusing the cell debris generated from PHA recovery, the invention avoids disposal of a large amount of aqueous waste. In addition, a remarkable increase of cell growth and PHA synthesis is achieved, because the cell debris can be readily assimilated by the microbial cells as the nutrients.

US Patent:

20190280620, Sep 12, 2019

Filed:

Nov 17, 2017

Appl. No.:

16/346676

Inventors:

- Honolulu HI, US
Jian Yu - Honolulu HI, US
Enze Ma - Durham NC, US

International Classification:

H02N 1/08

Abstract:

Apparatuses and methods for harvesting ambient energy involve repeated circuit reconfiguration. An apparatus includes a primary charge storage device, a first secondary charge storage device, a second secondary charge storage device, and switching circuitry. The switching circuitry is configured to cyclically alter connection of the first and second secondary charge storage devices between a series state and a parallel state. First and second moveable electrically conductive elements may include electrically conductive liquid droplets of materials such as water or mercury. At least one of the primary storage device, the first secondary charge storage device, or the second secondary charge storage device includes a capacitance that varies in response to receipt of ambient energy. Concurrently altering relative capacitance and circuit configuration results in exponential growth of harvested energy.

US Patent:

20190280621, Sep 12, 2019

Filed:

Nov 29, 2017

Appl. No.:

16/346679

Inventors:

- Honolulu HI, US
Jian Yu - Honolulu HI, US
Enze Ma - Durham NC, US

International Classification:

H02N 1/08

Abstract:

Systems, apparatuses and methods for harvesting ambient energy involve an electrically conductive charge-carrying movable electrode. An apparatus includes an electrically conductive charge-carrying electrode, a first dielectric interface region, a second dielectric interface region, and at least one reference electrode. The first and second dielectric interface regions differ in surface charge density. In certain aspects, the movable electrode moves proximate and relative to the first and second dielectric interface regions in response to receipt of ambient energy, thereby providing first and second capacitances. The first capacitance differs from the second capacitance, and/or the first surface charge density differs from the second surface charge density. Movement of the movable electrode in combination with the differing capacitances and/or charge densities results in energy accumulation, thereby enabling ambient energy to be harvested efficiently and effectively.

US Patent:

20170002385, Jan 5, 2017

Filed:

Jun 2, 2016

Appl. No.:

15/172071

Inventors:

- San Giorgio Di Piano (Bologna), IT
- MINERBIO (BOLOGNA), IT
Jian YU - Honolulu HI, US

International Classification:

C12P 7/62

Abstract:

The present invention relates to a process for producing biodegradable polymeric materials including polyhydroxyalkanoates (PHAs) by using the cell debris left from PHA recovery and purification. The process comprises: (a) cultivating PHA-producing microbial cells in a medium solution containing an organic carbon source to form PHAs that are accumulated in the cells as inclusion bodies; (b) harvesting the cells from the spent medium and solubilizing the non-PHA cell mass to obtain a PHA solid and a cell debris solution; (c) separating the PHA solid from the cell debris solution; (d) feeding the cell debris solution to the cultivation step (a). By reusing the cell debris generated from PHA recovery, the invention avoids disposal of a large amount of aqueous waste. In addition, a remarkable increase of cell growth and PHA synthesis is achieved, because the cell debris can be readily assimilated by the microbial cells as the nutrients.

US Patent:

20140377819, Dec 25, 2014

Filed:

Nov 17, 2011

Appl. No.:

14/358911

Inventors:

Jian Yu - Honolulu HI, US

Assignee:

BIO ON S.R.L. - San Giorgio Di Piano (BO)

International Classification:

C12P 7/62

US Classification:

435135

Abstract:

A process for producing hydroxyalkanoate copolymers, which comprises: (i) pre-treating a sucrose-containing feedstock in an acidic solution; (ii) feeding the pre-treated feedstock into a bioreactor containing polyhydroxyalkanoate producing microbial cells; (iii) cultivating the polyhydroxyalkanoate producing microbial cells to form a cell mass containing the hydroxyalkanoate copolymers; (iv) recoverying the hydroxyalkanoate copolymers from the cell mass. The pre-treating step has the main function of hydrolyzing sucrose into glucose and fructose, which in turn are converted into 4-ketovaleric acid to give a mixture of mono-saccharides and organic precursors for microbial synthesis of hydroxyalkanoate copolymers, and particularly of PHBVV ter-polymers. Complex and expensive purification processes of the substrates obtained from the pre-treating step are not needed. The solutions can be directly used as the feeding solutions for microbial PHA biosynthesis.