Ex Parte Retsina et al

Patent Trial and Appeal Board

Mar 31, 2017

12854869 (P.T.A.B. Mar. 31, 2017)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/854,869 08/11/2010 Theodora Retsina 0027 8737
104406 7590 04/04/2017
API Intellectual Property Holdings, LLC
c/o Ryan P. OConnor, Ph.D.
PO Box 580
Minnetrista, MN 55364
EXAMINER
PYLA, PAUL D
ART UNIT PAPER NUMBER
1653
NOTIFICATION DATE DELIVERY MODE
04/04/2017 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
roconnor @ americ anproces s. com
docket @ blackhillsip .com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte THEODORA RETSINA and VESA PYLKKANEN1
Appeal 2016-003863
Application 12/854,869
Technology Center 1600
Before DEMETRA J. MILLS, JOHN G. NEW, and TAWEN CHANG,
Administrative Patent Judges.
NEW, Administrative Patent Judge.
1 Appellants state the real parties-in-interest is API Intellectual Property
Holdings, LLC. App. Br. 2.
Appeal 2016-003863
Application 12/854,869
DECISION ON APPEAL
Appellants file this appeal under 35 U.S.C. § 134(a) from the
Examiner’s Final Rejection of claims 14—19, 23, 24, 26—28, and 30—332
which stand rejected as unpatentable under 35 U.S.C. § 103(a) as being
obvious over the combination of Hoge (US 4,009,075, Feb. 22, 1977)
(“Hoge”) and Yang et al. (US 2006/0088922 Al, April 22, 2006) (“Yang”).
Claims 14—19, 23, 24, 26—28, and 30-33 also stand rejected as
unpatentable under 35 U.S.C. §103(a) as being obvious over the
combination Yang and Ehnstrom (US 4,376,163, March 8, 1983)
(“Ehnstrom”).
We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
NATURE OF THE CLAIMED INVENTION
Appellants’ invention is directed to a method to reduce enzyme usage
for the breakdown of lignocellulosic material by enzymatic hydrolysis.
Enzyme activity is retained and enzymes are recycled back for the
hydrolysis of new lignocellulosic material after removal of fermentation
products using low temperature distillation. Abstract.
REPRESENTATIVE CLAIM
Claim 14 is representative of the claims on appeal and recites:
14. A process for converting a lignocellulosic material into a
fermentation product, said process comprising:
2 Claims 1—13, 20-22, 25, and 29 are canceled. App. Br. 17—19.
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(a) providing a lignocellulosic material;
(b) pretreating said lignocellulosic material to reduce its
lignin content, thereby producing pretreated lignocellulosic
material containing cellulose and lignin;
(c) contacting said pretreated lignocellulosic material with
an enzyme or mixture of enzymes to hydrolyze said cellulose to
fermentable sugars, wherein said enzyme or mixture of enzymes
includes cellulase enzymes;
(d) introducing additives or detergents to release said
enzymes from said lignin or to block non-specific binding of said
enzymes with said lignin;
(e) separating a lignin-containing solid residue from said
fermentable sugars, wherein said lignin-containing solid residue
is purged and not recycled;
(f) fermenting said fermentable sugars with a
microorganism to produce a dilute fermentation product in
aqueous solution;
(g) separating said microorganism from said aqueous
solution;
(h) distilling said aqueous solution under vacuum in a
distillation column to produce an overhead stream comprising
said fermentation product and a bottoms stream comprising said
enzyme or mixture of enzymes, wherein said distillation column
is operated at a maximum distillation temperature selected to
maintain activity of said enzyme or mixture of enzymes;
(i) recycling said bottoms stream containing said enzyme
or mixture of enzymes to step (c); and
(j) adding fresh enzymes to step (c) to replenish any loss
caused by purge of said lignin-containing solid residue from step
(e).
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App. Br. 17.
ISSUES AND ANALYSES
We agree with, and adopt, the Examiner’s findings and conclusion
that the appealed claims are prima facie over the combined prior art cited by
the Examiner. We address the arguments raised by Appellants below.
A. Rejection of the claims over the combination of Hoge and Yang
Issue
Appellants argue the Examiner erred because the combined cited prior
art references neither teach nor suggest the limitations of claim 14 reciting:
(1) “introducing additives or detergents to release said enzymes from said
lignin or to block non-specific binding of said enzymes with said lignin”; (2)
“separating a lignin-containing solid residue from said fermentable sugars,
wherein said lignin-containing solid residue is purged and not recycled”; (3)
“separating said microorganism from said aqueous solution”; or (4)
“distilling said aqueous solution under vacuum in a distillation column to
produce an overhead stream comprising said fermentation product and a
bottoms stream comprising said enzyme or mixture of enzymes, wherein
said distillation column is operated at a maximum distillation temperature
selected to maintain activity of said enzyme or mixture of enzymes.” App.
Br. 9-10.
Analysis
The Examiner finds that Hoge teaches a method for making alcohol
from cellulosic material by hydrolyzing the material to sugars and subjecting
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the resultant reaction mixture to digestion and fermentation to convert the
sugars to alcohol via a sterilization step, a concurrent digestion and
fermentation step, and acid removal step. Non-Final Office Action, June 20,
2014, 4 (“Non-Final Act.”) (citing Hoge col. 1,11. 45—65). The Examiner
finds Hoge further teaches that if the fibrous material is a woody material
with a high lignin content, lignin-attacking agents such as the pleiotropic
mutants of the wood-rotting fungus Polyporus adustus, can be included.
This is interpreted by the Examiner as meaning lignin-containing solid
residues are purged (i.e., the fermentable sugars are made free due to the
breakdown of lignin via enzymes), and not recycled. Non-Final Act. 6—7.
The Examiner further finds that:
[Although Hoge does not perform the separation step prior to
distilling off the ethanol, as currently claimed, it would have been
obvious to perform the separation step prior to distillation as
claimed since Hoge teaches [...] that where desired, the non­
volatile portion can be concentrated. This can be interpreted as
that since the fermentation has produced a volatile fraction, the
nonvolatile fraction can be separated out prior to distillation so
that the microorganisms in the non-volatile fraction can be
recycled, and thus making when the microorganism is separated
out post fermentation inconsequential.
Final Act. 6.
The Examiner also finds:
Yang teaches a method utilizing] a protein and/or polypeptide
that preferentially binds with lignin more readily than cellulose
where a biomass is treated with a lignin blocking protein and/or
polypeptide (e.g., albumin, soybean protein, amylase (and
combinations thereof)), by washing the biomass with a
composition that comprises the lignin-blocking protein and/or
polypeptide or by adding such materials to a saccharification
broth (paragraph 32).
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The teachings are interpreted as lignin-containing solid
residues are purged (i.e., the fermentable sugars are made free
due to the breakdown of lignin via enzymes), and not recycled.
Final Act. 4—5.
Appellants argue that the wood-rotting fungus Polyporus adustus does
not “release said enzymes from said lignin or [ ] block non-specific binding
of said enzymes with said lignin” (step (d) of claim 14), but rather
enzymatically degrades lignin itself.3 App. Br. 10 (citing K.E. Eriksson and
W.E. Goodell, Pleiotropic mutants of the wood-rotting fungus Polyporus
adustus lacking cellulase, mannanase, and xylanase, 20(3) Can. J.
Microbiol. 371—78 (1974)) (“Ericksson”). Furthermore, Appellants argue,
the enzymatic degradation of lignin taught by Hoge is irrelevant to the
recycling or purging of lignin, as the lignin in Hoge is neither not recycled
nor purged. Id.
Appellants next argue that Hoge neither teaches nor suggests
removing organisms before distillation as required by the claims. App. Br.
11. Appellants dispute the Examiner’s conclusion that it would have been
obvious to a person of ordinary skill in the art to perform the separation step
prior to distillation as claimed, because Hoge teaches that, where desired, the
3 Although Appellants point to limitations in claim 28 that they contend are
not met by the combination of Hoge and Yang, they do not separately argue
the claims. In reLovin, 652 F.3d 1349, 1357 (Fed. Cir. 2011) (“[T]he Board
[has] reasonably interpreted Rule 41.37 to require more substantive
arguments in an appeal brief than a mere recitation of the claim elements and
a naked assertion that the corresponding elements were not found in the
prior art.”) In any event, the limitations Appellants point to in claim 28 are
similar to those in claim 14. Accordingly, we focus our analysis on claim 14
as representative.
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non-volatile portion can be concentrated. Id. (citing Final Act. 6—7).
Appellants state the Examiner finds this teaching can be interpreted as
meaning that, since the fermentation has produced a volatile fraction, the
nonvolatile fraction can be separated out prior to distillation so that the
microorganisms in the non-volatile fraction can be recycled. Id. Appellants
argue further that Hoge’s teaching of a non-volatile portion being
concentrated, means removal of a liquid phase or volatile phase. Id. at 12.
Appellants contend it would be unconventional in the terminology of the art
to refer to separation of solids out of a stream as the solids being
concentrated. Id. Furthermore, argue Appellants, Hoge teaches that the
distillation bottoms contain active enzymes and yeasts, whereas the claims
on appeal require the yeasts to be removed prior to distillation; the
distillation bottoms therefore contain enzymes but do not contain yeasts. Id.
(citing Hoge col. 2,1. 20). Similarly, Appellants argue, Hoge also teaches
that the non-volatile portion contains enzymes and yeasts. Id. (citing Hoge
col. 3,1. 62). Appellants contend the step of “separating said microorganism
from said aqueous solution” recited in conjunction with the bottoms stream
containing enzymes, i.e., the enzymes not being separated out, does not
correspond to a nonvolatile portion containing enzymes and yeasts, as taught
by Hoge, whether from the viewpoint of what is separated or of what
remains. Id.
Appellants further contend the purpose of the teaching of Hoge with
respect to keeping temperatures below about 30°C by vacuum is to keep the
yeast active, not the enzymes. App. Br. 12. Appellants argue Hoge does not
teach or suggest:
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[DJistilling said aqueous solution under vacuum in a distillation
column to produce an overhead stream comprising said
fermentation product and a bottoms stream comprising said
enzyme or mixture of enzymes, wherein said distillation column
is operated at a maximum distillation temperature selected to
maintain activity of said enzyme or mixture of enzymes,
as recited in the claims. Id.
With respect to the Examiner’s findings concerning the teachings of
Yang, Appellants contend that Yang does not disclose an additive that
“release[s] said enzymes from said lignin or ... block[s] non-specific binding
of said enzymes with said lignin.” App. Br. 11. Rather, argue Appellants,
the additive disclosed by Yang reacts with lignin and does not prevent
unreacted lignin from non-specific binding of enzymes to lignin: Appellants
assert “non-specific” here means “not to cellulose.” Id.
Furthermore, according to Appellants, the Examiner’s interpretation
of the teachings of Yang corresponding to the claim language reciting
“lignin-containing solid residues are purged (i.e., the fermentable sugars are
made free due to the breakdown of lignin via enzymes), and not recycled” is
technically incorrect, because the lignin is not broken down via enzymes in
the method taught by Yang. App. Br. 11. Appellants assert that a protein
such as soybean protein is introduced to react with lignin; lignin does not
decompose (as Appellants admit it does in the teachings of Hoge). Id.
Appellants argue that sugars are not freed by the reaction of the protein with
lignin, as taught by Yang. Id.
Appellants argue further that, assuming arguendo that sugars are
liberated in the method taught by Yang, the lignin or lignin-containing solids
(i.e., the protein-lignin complex) are not purged. App Br. 11. Appellants
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ague Yang does not teach that such solids are purged, nor do the Examples
provided in Yang teach purging the protein-lignin complex, as required by
the claims. Id.
The Examiner responds, first, that Appellants cannot show
nonobviousness by attacking references individually where the rejections are
based on combinations of references. Ans. 22 (citing, e.g., In re Keller, 642
F.2d 413, 426 (C.C.P.A. 1981)).
The Examiner finds that Hoge teaches lignin-containing solid residues
are purged by the process of rotting induced by the fungus Polypoms
adustus. Ans. 24. The Examiner finds that, because the fungus rots the
lignin-containing wood, it is “purged” and not recycled. Id. Moreover, the
Examiner finds, the fermentable sugars are separated and “made free” due to
the breakdown of lignin via enzymatic action. Id.
Absent an explicit definition of the claim term “purge” in Appellants’
Specification, the Examiner gives the term the broadest reasonable definition
in view of the Specification. Ans. 24—25 (citing MPEP § 2111). The
Examiner therefore interprets the claim term “purge”, based on its dictionary
definition as meaning “to get rid of’ or “to remove or eliminate.” Id. at 25
(citing “purge” in The Free Dictionary, available at:
www.thefreedictionary.com/purge (last visited October 21, 2015)).
The Examiner finds that the combined teachings of Hoge and Yang teach
removing lignin from the system by adding additives that either degrade
lignin or bind lignin so as to block lignin binding to the enzymes, which, in
view of the Examiner’s interpretation of “purge,” is interpreted within the
process as getting rid of, removing, or eliminating lignin. Id.
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With respect to Appellants’ argument that a non-volatile portion being
concentrated means removal of a liquid phase or volatile phase, and that it
would be unconventional terminology in the art to refer to separation of
solids out of a stream as the solids being concentrated, the Examiner finds
the broadest reasonable interpretation of the “non-volatile portion being
concentrated” can be reasonable interpreted as meaning “the separation of
solids out of a stream.” Ans. 26. The Examiner adopts this interpretation
because, the Examiner finds, it is known in the art to concentrate solids in
the stream, either for recycling or to concentrate the solids by themselves for
eventual removal out of the process for use as other products. Id. The
Examiner again observes that Appellants’ claims and Specification employ
broad terms and standard definitions, which are subject to the broadest
reasonable interpretation consistent with Appellants’ Specification. Id.
With respect to Appellants’ contention that the “enzymes not being
separated out” cannot be equated with the “non-volatile portion containing
enzymes and yeasts,” the Examiner finds Hoge teaches that the non-volatile
portion contains unreacted materials and that non-volatile portion of the
reaction mixture may be concentrated by ultrafiltration. Ans. 26. The
Examiner finds it is well-known in the art that lignin can be broken down via
enzymes, solubilized (e.g., as lignin sulfonate or solubilized within an
organosolvent process), precipitated, and then separated out by a process
(e.g., ultrafiltration) so that cellulose is isolated for further attack by
enzymes such as cellulases to produce fermentable sugars for eventual
alcohol production. Id. The Examiner therefore finds the combined
teachings of Hoge and Yang teach that lignin-containing solid residues (i.e.,
lignin and protein-bound lignin) can be separated from the fermentable
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sugars and any remaining lignin in the process can be separated out using
known separation techniques. Id.
We are not persuaded by Appellants’ arguments. As an initial matter,
we agree with the Examiner that Appellants may not attack individual
references separately when the Examiner has relied upon a combination of
the references. Keller, 642 F.2d at 426. Rather, the proper test for
obviousness “is what the combined teachings of the references would have
suggested to those of ordinary skill in the art.” Id. at 425.
Claim 14 recites: “pretreating said lignocellulosic material to reduce
its lignin content, thereby producing pretreated lignocellulosic material
containing cellulose and lignin.” Hoge, as the Examiner finds, teaches that
in a process for making alcohol from cellulose material, wherein “the fibrous
material is [a] woody material with a high lignin content, e.g. sawdust, it is
desirable to include lignin-attacking agents such as the pleiotropic mutants
of the wood-rotting fungus Polyporus adustus.” Hoge col. 5,11. 20—25. We
agree with the Examiner that this teaching of Hoge reads on the limitation
recited above.
We also disagree with Appellants’ argument that neither reference
teaches or suggests the limitation reciting “introducing additives or
detergents to release said enzymes from said lignin or to block non-specific
binding of said enzymes with said lignin.” App. Br. 11. Yang explicitly
teaches:
In one embodiment, the method utilizes a protein and/or
polypeptide that preferentially binds with lignin more readily
than cellulose. A high lignin-content biomass is treated with the
lignin blocking protein and/or polypeptide, for example by
washing the biomass with a composition that comprises the
lignin-blocking protein and/or polypeptide or by adding such
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materials to a saccharification broth. The lignin-blocking
polypeptide and/or protein preferentially bind and thereby
impede the lignin from further binding.
Yang | 32.4 We therefore agree with the Examiner that Yang explicitly
teaches the limitation of claim 14 reciting “or to block non-specific binding
of said enzymes with said lignin.” See Ex Parte Thelen, Appeal No. 2009-
015263, 2012 WL 2522441, at *2 (BPAI, June 28, 2012) (An “or” limitation
is anticipated [or obvious] if one of the (alternate) requirements is disclosed
by a prior art reference).
We are similarly not persuaded by Appellants’ arguments that the
combined cited prior art references fail to teach “separating a lignin-
containing solid residue from said fermentable sugars, wherein said lignin-
containing solid residue is purged and not recycled,” as recited in the claims.
App. Br. 11. Yang teaches:
The [post lignin-treated] slurry travels to a heated
hydrolysis reactor vessel 144, which may be one of a series of
such reactor vessels, for an appropriate residence time permitting
hydrolysis of the slurry.
Slurry discharge from the hydrolysis reactor 144 may be
subjected to additional mixing at a fourth mixing station 154,
which adds a second stream 156, such as an aqueous stream with
additional enzymes or a microorganism-containing stream useful
for conversion processes, i.e., the conversion of sugars into
4 Parenthetically, Yang also teaches it is well-known in the art that: “In high
lignin content lignocellulosic biomass, high doses of cellulase are needed to
degrade the cellulose with high yields because the lignin binds preferentially
with the cellulase, thereby reducing access of cellulase to cellulose,” thus
providing motivation to prevent lignin-cellulase binding. Yang 111
(emphasis added).
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alcohols. The second stream 156 reacts in a converter reactor
158, for example, to convert sugars into alcohol or other organic
compounds. Discharge from converter reactor 158 may be
submitted to a vortex separator 160, which discharges solids to
waste disposal where the solids may, for example, be used as a
boiler fuel. Liquids from vortex separator are submitted to
distillation column 162, which concentrates useful products, e.g.,
ethanol, for further downstream processing 164, such as a
molecular filter to remove water. Remaining liquids and/or
solids from the distillation column 162 are submitted to recycle
processing 166, for example, to filter fine particulates and add
acid for use of such liquids as the acidification solution 112.
Yang || 72—73. We acknowledge that, in this embodiment of Yang, the
solids (including lignin) are removed (step (e) of claim 1) after the
fermentation step (i.e., after the conversion of sugars into alcohols) (step (f)
of claim 1), but there is nothing in the language of the claims that explicitly
or inherently requires that the recited steps be performed in the order recited
in the claims. Unless the steps of a method actually recite an order, the steps
are not ordinarily construed to require one. Interactive Gift Exp., Inc. v.
CompuServe Inc., 256 F.3d 1323, 1342—43 (Fed. Cir. 2001) (citing Loral
Fairchild Corp. v. Sony Corp., 181 F.3d 1313, 1322 (Fed. Cir. 1999) (“[N]ot
every process claim is limited to the performance of its steps in the order
written”)). However, such a result can ensue when the method steps
implicitly require that they be performed in the order written. See Loral, 181
F.3d at 1322. In this instance, Appellants have made no argument or
adduced any evidence to suggest that the “purging” step (e) of their claims
must precede the fermentation step (f). Indeed, the passages of Yang recited
supra strongly indicate that there is no such necessity.
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Finally, with respect to the claim term “purge” we agree with the
Examiner that, absent an explicit definition in Appellants’ Specification, the
Examiner may adopt the broadest reasonable interpretation consistent with
the Specification. See In re ICON Health & Fitness, Inc., 496 F.3d 1374,
1379 (Fed. Cir. 2007) (explaining that [cjlaims under examination before the
PTO are given their broadest reasonable interpretation consistent with the
specification). Yang teaches that the solid components, post-fermentation,
are “discharge[d] ... to waste disposal” or “submitted to recycle processing
166.” (Yang 173.) We agree with the Examiner that such actions
correspond to “purging,” as recited in the language of the claims, in the
sense that they are “[gotten] rid of’ or “remove[d] or eliminate[d].” See
Ans. 25.
Appellants next argue that the combined references fail to teach or
suggest the limitations of claim 14 reciting: “(g) separating said
microorganism from said aqueous solution” and:
(h) distilling said aqueous solution under vacuum in a distillation
column to produce an overhead stream comprising said
fermentation product and a bottoms stream comprising said
enzyme or mixture of enzymes, wherein said distillation column
is operated at a maximum distillation temperature selected to
maintain activity of said enzyme or mixture of enzymes
Ans. 26. Specifically, Appellants argue that the microorganisms are not
separated prior to distillation. App. Br. 26. We are not persuaded. Hoge
explicitly teaches:
b. The removal of the reaction products may be carried out in a
continuous or intermittent manner in order to force the
reactions to completion. Sugar formed by the enzymatic
breakdown of the cellulose is immediately removed when it
is fermented by the yeasts. The alcohol formed by the
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fermentation of the sugars is likewise continuously removed
by the vacuum distillation.
c. The bottoms or solution which remains after the sugar and
alcohol production is completed will still retain active
cellulase enzyme and yeasts, and this innoculum [sic]
solution, therefore, may be recycled to dilute new quantities
of incoming sterilized cellulosic fibers.
Hoge col. 2,11. 10-23 (emphases added). We acknowledge that, in these
steps, Hoge does not teach that the microorganisms (i.e., the yeasts) prior to
distillation; the yeasts remain in the bottoms or remaining solution.
However, Hoge also teaches:
The removal of the alcohol at this relatively low temperature
permits recycling and reuse of the non-volatile portion of the
reaction mixture to replace dilution water and to reduce the
amount of innoculum [sic] needed for the next batch. This non­
volatile portion contains yeast, cellulase enzyme and unreacted
materials. Where desired, the culture or non-volatile portion of
the reaction mixture may be concentrated by ultrafdtration as
commonly practiced.
Hoge col. 3,11. 58—66. Hoge thus teaches that the culture, i.e., the yeasts,
may be removed from the bottoms (the non-volatile portion). Although
Hoge does not require that this happen prior to vacuum distillation, neither
does the language of claim require that this step precede distillation. See
Loral, 181 F.3d at 1322. Furthermore, Appellants do not argue that the
separation step must proceed the distillation step for Appellants’ invention to
function. Id. at 1322. Appellants’ Specification states merely that: “The
yeast is separated from the beer after the fermentation,” without further
elaboration as to when in the process this step occurs. Spec. 112. We agree
with the Examiner that any such variation in the order of the procedural
steps would be within the creativity of a person of ordinary skill. See KSR
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Int’l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007) (“If a person of ordinary
skill can implement a predictable variation, § 103 likely bars its
patentability”).
Finally, Appellants argue that the references fail to teach or suggest
the limitation of claim 14 reciting: “wherein said distillation column is
operated at a maximum distillation temperature selected to maintain activity
of said enzyme or mixture of enzymes,” as required by the claims. App. Br.
12. Appellants contend that the purpose of Hoge’s teaching of keeping
temperatures below about 30°C by vacuum is to keep the yeast active, rather
than the enzymes. Id.
We are not persuaded, finding this to be a distinction without a
difference. As is well known in the art, cellulase hydrolyzes cellulose to
fermentable sugars as an initial step in the fermentation process. Spec. 111.
Enzymes, including cellulase, have generally evolved to function in
temperature ranges within which the organism synthesizing the enzyme can
survive as well, although cellulase can function at slightly higher
temperatures as well. See Hoge col. 3,11. 41—47. Appellants adduce no
evidence to suggest that cellulase secreted by yeasts cannot function within
the temperature ranges (30-45°C or less) taught by Hoge. See Spec. |13
(stating that “activity for one type of cellulase occurs between 30 and 70-C,
with the peak around 50-C”).
Because we agree with the Examiner’s conclusion that the
combination of Hoge and Yang teach or suggest the limitations of
Appellants’ claims on appeal, we affirm the Examiner’s rejection.
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B. Rejection of the claims over the combination of Yang and Ehnstrom
Issue
Appellants argue that the Examiner erred because the combined cited
prior art references fail to teach or suggest the limitations of claim 14
reciting: (1) “introducing additives or detergents to release said enzymes
from said lignin or to block non-specific binding of said enzymes with said
lignin”; (2) “separating a lignin-containing solid residue from said
fermentable sugars, wherein said lignin-containing solid residue is purged
and not recycled”; (3) “separating said microorganism from said aqueous
solution”; (4) “distilling said aqueous solution under vacuum in a distillation
column to produce an overhead stream comprising said fermentation product
and a bottoms stream comprising said enzyme or mixture of enzymes,
wherein said distillation column is operated at a maximum distillation
temperature selected to maintain activity of said enzyme or mixture of
enzymes”; or (5) “recycling said bottoms stream containing said enzyme or
mixture of enzymes to step (c).”5 App. Br. 12—13.
Analysis
With respect to limitations (1) and (2), we have already explained
supra why we find that Yang teaches these limitations. Appellants make no
5 Appellants also point to limitations in claim 28 that they contend are not
met by the combination of Yang and Ehnstrom. As discussed above,
however, “a mere recitation of the claim elements and a naked assertion that
the corresponding elements were not found in the prior art” does not suffice
for purposes of separately arguing the claims. In re Lovin, 652 F.3d at 1357.
Moreover, the limitations Appellants point to in claim 28 are similar to those
in claim 14. Accordingly, we focus our analysis on claim 14 as
representative.
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arguments with respect to the teachings of Yang with respect to limitations
(3H5).
Appellants argue Ehnstrom is relied upon by the Examiner as teaching
“recycling said bottoms stream containing said enzyme or mixture of
enzymes.” App. Br. 13. Appellants assert that Ehnstrom teaches enzymes
are not consumed, but are recirculated, where high enzyme concentrations
are permissible. Id. (citing Ehnstrom col. 4,11. 38—41). According to
Appellants, the recirculation of enzymes taught by Ehnstrom is not the same
as the recycling of enzymes as recited in Appellants’ claims. Id. Rather,
argue Appellants, Ehnstrom teaches enzymes are internally recycled
(recirculated) from an additional evaporator (hydrolysis unit) back to the
fermentor: once material reaches the stripping column and rectification
column, there is no recycle of enzymes. Id. (citing Ehnstrom Figure; col. 2,
1. 56 et seq.). Appellants assert that this is in contrast to Appellants’ claimed
invention, which requires recycling a distillation column bottoms stream
containing enzymes. Id.
The Examiner responds that Ehnstrom teaches a process for producing
ethanol by continuous fermentation where a stream of fermentation liquor is
separated into a yeast concentrate stream and a yeast-free stream, and in
which the yeast concentrate stream is recirculated to the fermenter, while at
least part of the yeast-free stream is fed to a saccharifying reactor that
corresponds to one or a few distilling stages, where the yeast-free stream is
separated partly into a first vapor stream (ethanol) and partly into a first
liquid bottom stream which is at least in part recirculated to the fermenter.
Ans. 31 (citing Ehnstrom Abstr., col. 2,11. 3—5; col. 4,11. 23—25).
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The Examiner finds the circuit sub-processes within Ehnstrom can be
reasonably interpreted to encompass the distillation step within the claims,
where yeast is separated continuously from the feed stream by the
centrifugal separator, which is provided to separate the incoming
fermentation feed liquor into a yeast concentrate stream (which is
recirculated back to the fermenter) and a yeast-free stream (which is fed to
the saccharifying reactor to the fractionation column.) Id. (citing Ehnstrom
col. 2,11. 61—67, col. 4,1. 27—30). The Examiner finds the yeast is recycled
in the form of a yeast concentrate, back to the fermenter. Id. (citing
Ehnstrom col. 4,11. 30—33). The Examiner finds the other stream, the yeast-
free stream, is pumped to the saccharifying reactor, where a vapor stream,
enriched in ethanol, is driven off simultaneously (to the fractionation
column) while the saccharifying of prehydrolyzed starch is fed to the
fermenter. Id. (citing Ehnstrom col. 4,11. 34—38). The Examiner finds the
enzymes are not consumed, but are recirculated, where high enzyme
concentrations are permissible. Id. (citing Ehnstrom col. 4,11. 38-41).
Appellants argue Ehnstrom neither teaches nor suggests the limitation
of claim 14 reciting: “recycling said bottoms stream containing said enzyme
or mixture of enzymes.” App. Br. 13. We do not agree. Ehnstrom teaches:
The fermentor 1 is a [sic] connected, via a line 8 to the centrifugal
separator 2, which is provided to separate the incoming feed of
fermentation liquor partly into a yeast concentrate stream, which
is recirculated to the fermentor via a line 9, partly into a yeast-free
stream, which is fed, via a line 10 to the evaporation unit 3, and
into a smaller part-stream, by bifurcation from the line 10 to a line
11, which is connected to the stripping unit 4....
Ehnstrom cols. 2—3,11. 61—1. We agree with the Examiner that Ehnstrom
thus teaches that, after fermentation has occurred, the resulting stream is
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separated into a yeast concentrate stream (which either contains or
necessarily produces enzymes) back to the fermentor for another round of
fermentation. We consequently agree with the Examiner that Ehnstrdm
teaches or suggests the disputed limitation and we affirm the Examiner’s
rejection.
C. The combination of the references by the Examiner
Issue
Appellants argue the Examiner erred because the prior art as a whole
does not make the invention “obvious to anyone skilled in the art.” App. Br.
14.
Analysis
Appellants repeat their arguments presented in sections A and B
supra. App. Br. 14. In addition, Appellants argue further that none of the
prior art references cited by the Examiner teach or suggest the limitation
reciting “adding fresh enzymes to replenish any loss caused by the purge of
lignin-containing solid residue.” Id. Appellants do not point to any error in
the Examiner’s findings, or cite any supporting evidence, to demonstrate that
the references fail to teach or suggest this limitation.
Appellants’ bare assertions, unsupported by evidence, are insufficient
to sustain their arguments. See In re De Blauwe, 736 F.2d 699, 705 (Fed.
Cir. 1984) (stating that “[arguments and conclusions unsupported by factual
evidence carry no evidentiary weight). Consequently, we affirm the
Examiner’s rejection of the claims.
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Furthermore, we agree with the Examiner that both Hoge and
Ehnstrom teach that fresh enzyme or recycled enzyme can be used for the
next batch run. See Final Rej. 5. Hoge teaches that the recycled material
can be used to reduce the amount of new enzymes in the next batch. See
Hoge col. 4,11. 50—58. We agree with the Examiner’s conclusion that it
would have been obvious to one of ordinary skill in the art to provide
additional enzymes during the ensuing ethanol production runs since a
person of ordinary skill in the art would recognize when ethanol yield is
dropping and would want to correct this in order to maintain high production
yields in the current batch or subsequent batches. Id. We consequently
affirm the Examiner’s rejection of the claims.
DECISION
The Examiner’s rejection of claims 14—19, 23, 24, 26—28, and 30-33
as unpatentable under 35 U.S.C. § 103(a) over Hoge and Yang is affirmed.
The Examiner’s rejection of claims 14—19, 23, 24, 26—28, and 30-33
as unpatentable under 35 U.S.C. § 103(a) over Yang and Ehnstrom is
affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1). See 37 C.F.R.
§ 1.136(a)(l)(iv).
AFFIRMED
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