XYLECO, INC.

Patent Trials and Appeals Board

Aug 6, 2020

2020000522 (P.T.A.B. Aug. 6, 2020)

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.
15/288,121 10/07/2016 Marshall Medoff 08895-0073007 7460
7590 08/06/2020
Xyleco, Inc.
360 Audubon Road
Wakefield, MA 01880
EXAMINER
ARIANI, KADE
ART UNIT PAPER NUMBER
1651
MAIL DATE DELIVERY MODE
08/06/2020 PAPER
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.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MARSHALL MEDOFF and THOMAS CRAIG MASTERMAN
Appeal 2020-000522
Application 15/288,121
Technology Center 1600

Before ERIC B. GRIMES, RACHEL H. TOWNSEND, and
CYNTHIA M. HARDMAN, Administrative Patent Judges.
HARDMAN, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134(a) involving claims related to
a mixture comprising a low molecular weight sugar, a fermenting natural
yeast, and an irradiated lignocellulosic material with certain porosity and
surface area characteristics. The Examiner rejected the claims as obvious
under 35 U.S.C. § 103(a). We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

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Application 15/288,121

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CLAIMED SUBJECT MATTER
Claims 19–26 and 28 are pending. Final Act. 2. Claim 19,
reproduced below, is illustrative of the claimed subject matter:
19. A mixture comprising:
an aqueous solution comprising a low molecular weight
sugar,
a fermenting natural yeast, and
a lignocellulosic material that has been irradiated with at
least 10 Mrad of electron beam radiation, the lignocellulosic
material having a BET surface area greater than 0.1 m2/g and a
porosity greater than 50%.
Appeal Br. 13 (Claims Appendix).
REJECTIONS
Claims 19–24, 26, and 28 stand rejected under 35 U.S.C. § 103 as
being unpatentable over Bhatt1 and Yu.2 Final Act. 4.
Claims 19–26 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Bhatt, Yu, and Chodsu.3 Id. at 6.
OPINION
The same issues are dispositive of both pending rejections; thus, we
address the rejections together.

1 Bhatt et al., Effect of Gamma Irradiation Pretreatment on Biodegradation
of Forest Lignocelluloses by Aspergillus Niger, 6(2) Biotechnology
Techniques, 111–114 (1992) (“Bhatt”).
2 Yu et al., An Novel Immobilization Method of Saccharomyces cerevisiae
to Sorghum Bagasse for Ethanol Production, 129 Journal of Biotechnology,
415–420 (2007) (“Yu”).
3 Chodsu et al., Radiation and Chemical Pretreatment of Cellulosic Waste,
42 Radiation Physics and Chemistry, 695–698 (1993), Abstract only
(“Chodsu”).
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The Examiner found that Bhatt teaches a mixture comprising an
aqueous solution comprising a low molecular weight sugar, a fermenting
microorganism (the fungus A. niger), and a lignocellulosic material that has
been irradiated with at least 10 Mrad (1.68 x 108 rad) of electron beam
radiation. Final Act. 4. The Examiner further found that because Bhatt
discloses a lignocellulosic material irradiated with the claimed amount of
radiation, “the claimed properties not disclosed by Bhatt et al., i.e., a BET
surface area greater than 0.1 m2/g, [and] a porosity of greater than 50%, . . .
must necessarily be present and are inherent properties of the irradiated
lignocellulosic material.” Id. at 4–5.
The Examiner found that Bhatt does not teach a fermenting natural
yeast as claimed, but Yu teaches fermenting a low molecular weight sugar in
a medium with a fermenting natural yeast (S. cerevisiae) in the presence of a
lignocellulosic material (bagasse). Id. at 5. The Examiner found that a
person of ordinary skill in the art would have been motivated to substitute
the fermenting yeast taught by Yu for the fermenting microorganism taught
by Bhatt, because substitution of one microorganism for another taught by
the prior art for the same purpose (fermenting low molecular weight sugar)
would have been obvious. Id. at 5–6.
Appellant argues that the Examiner has not established a prima facie
case of obviousness because Yu “uses a ‘laboratory mutant strain of baker
yeast 3013,’” not a natural yeast as recited in the claims. Appeal Br. 5
(quoting Yu Section 2.1). We are not persuaded by this argument.
Although Yu used a laboratory mutant strain of S. cerevisiae in its
experiment (see Yu at 416), Yu’s teachings are more broadly directed to a
technique for improving ethanol fermentation by immobilizing yeast cells in
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a lignocellulosic material (sorghum bagasse). See, e.g., Yu at Title (“A[]
Novel Immobilization Method of Saccharomyces cerevisiae to Sorghum
Bagasse for Ethanol Production”), Abstract (“Natural sorghum bagasse
without any treatment was used to immobilize Saccharomyces
cerevisiae . . . .”), 415 (discussing “[e]thanol production by immobilized
yeast cells”), 415–16 (discussing the advantages of sorghum bagasse as a
“yeast cell carrier”); 416 (“The present paper . . . delineates a novel and
simple technique for the rapid and strong immobilization of cells in sorghum
bagasse and also discusses the application of sorghum bagasse containing
the yeast cells for the ethanol fermentation.”), 420 (“Sorghum bagasse has a
potential as a carrier for the whole yeast cell immobilization using this
innovative method.”). Appellant has not directed us to anything in Yu that
suggests the disclosed techniques are limited to mutant strains of yeast.
Rather, we find that Yu’s teachings are broadly directed to yeast, whether
natural or mutant strains.
Appellant additionally asserts that the Examiner has not established a
motivation to combine, because Bhatt discloses the use of A. niger for
saccharification, whereas Yu discloses the use of S. cerevisiae for
fermentation. Id. at 6. We are not persuaded by this argument. Bhatt
recognizes the use of lignocellulosic material in fermentation. Bhatt 111
(“[T]here is a great deal of interest in the development of viable economic
processes allowing maximum utilization of lignocelluloses through their
microbial conversion to simple sugars which in turn can be utilized for the
production of alcohol fuels.”). Additionally, we agree with the Examiner
that a person of ordinary skill in the art would have known that A. niger is a
fermenting microorganism. See, e.g., Final Act. 3 (citing Gawande et al., 87
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Journal of Applied Microbiology 511–519, 512 (1999)). Appellant did not
dispute this finding. Accordingly, Appellant has not persuaded us of
Examiner error with regard to the finding that a person of ordinary skill in
the art would have been motivated to substitute the fermenting
microorganism taught by Bhatt with the fermenting yeast taught by Yu.
Appellant additionally argues that the Examiner has not established a
prima facie case of obviousness because the asserted prior art combination
does not disclose a “lignocellulosic material having a BET surface area
greater than 0.1 m2/g and a porosity greater than 50%” as claimed. Appeal
Br. 6. To meet these claim limitations, the Examiner relied on inherency,
but Appellant argues that “the Examiner has not provided a technical reason
why the recited BET surface area and the porosity values necessarily result
from irradiating lignocellulosic material.” Id. at 6–7. We agree with
Appellant that the Examiner has not established the required BET surface
area and porosity of the lignocellulosic material is inherently present in
Bhatt. As noted by Appellant, Table 24 in the Specification indicates that
“[i]n some cases, BET surface area increases with increasing doses of
irradiation, but in other cases, BET surface area decreases with increasing
doses of irradiation,” id. at 9, and “[n]o relationship between irradiation,
surface area, and porosity is recited in the claims.” Reply Br. 4. As such,
Appellant has persuaded us that “there is no general relationship between
BET surface area and amount of irradiation.” Id.
In support of the inherency argument, the Examiner cited Chesson et
al., Cell Wall Porosity and Available Surface Area of Wheat Straw and
Wheat Grain Fractions, 75 J. Sci. Food Agric., 289–295 (1997), for the
proposition that “interaction between polymers in the lignocellulosic
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material (plant cell wall) defines the porosity and surface area (physical)
properties of the lignocellulosic material.” Ans. 9. Even accepting this
proposition as true, it is irrelevant to whether there is an inherent relationship
between the claimed radiation dose and the claimed BET surface area and
porosity. As noted by Appellant, Chesson neither states that “a particular
porosity or surface area flows from irradiating lignocellulose,” nor
“discuss[es] irradiating lignocellulose.” Appeal Br. 10.
The Examiner also cited Khan et al., γ-Radiation Induced Changes in
the Physical and Chemical Properties of Lignocellulose,
7 Biomacromolecules 2303–2309 (2006), as showing it was “very well-
known in the art that gamma irradiation dose dependently induces structural
changes in the lignocellulosic material, for example, chain scission,
degradation of links between lignin, hemicellulose, and cellulose units in
lignocellulose, etc.” Ans. 9. However, even accepting as true that
irradiation induces structural changes, the Examiner has not established that
the specific radiation dose used in Bhatt (1.68 x 108 rad, see Bhatt 112)
necessarily results in a lignocellulosic material having a BET surface area
greater than 0.1 m2/g and a porosity of greater than 50%, as recited in the
claims. Accordingly, the Examiner has not satisfied the initial burden of
presenting a prima facie case of unpatentability. See In re Oetiker, 977 F.2d
1443, 1445 (Fed. Cir. 1992).
CONCLUSION
We reverse the rejection of claims 19–24, 26, and 28 under 35 U.S.C.
§ 103 as being unpatentable over Bhatt and Yu.
We reverse the rejection of claims 19–26 under 35 U.S.C. § 103 as
being unpatentable over Bhatt, Yu, and Chodsu.
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DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
19–24, 26,
28
103 Bhatt, Yu 19–24, 26,
28
19–26 103 Bhatt, Yu, Chodsu 19–26
Overall
Outcome:
19–26, 28
REVERSED