DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued examination under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e) was filed after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.114 has been timely paid, the finality of the previous Office Action has been withdrawn pursuant to 37 CFR 1.114. Applicant’s submission filed on 04/27/2026 has been entered.
Claim status
The examiner acknowledged the amendment made to the claims on 04/27/2026.
Claims 1, 4-6, 8, 10-12, 14-16, 23-24 and 27-28 are pending in the application. Claim 1 is currently amended. Claims 2-3, 9, 13, 18, 19, 20, 21, 22, 25-26 and 29-31 remain cancelled. Claims 7, 17 and 32 are newly cancelled. Claims 4-6, 8, 12, 14, 23-24 and 27-28 are withdrawn without traverse in view of the restriction requirement (see “Election/Restriction” above). Claims 10-11 and 15-16 are previously presented. Claim 32 is newly presented. Claims 1, 10-11 and 15-16 are hereby examined on the merits.
Examiner Note
Any objections and/or rejections that are made in the previous actions and are not repeated below, are hereby withdrawn.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 10-11 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Kang US Patent Application Publication No. 2013/0164801 A1 (hereinafter referred to as Kang) in view of Tong US Patent Application Publication No. 2018/0125092 A1 (hereinafter referred to as Tong) and Tyson US Patent No. 3,026,176 (hereinafter referred to as Tyson).
Regarding claims 1, 10 and 16, Kang teaches a method for manufacturing a butyrate product (0017; Fig. 2), comprising (i) providing a carbon-source-comprising fermentation feedstock (e.g., carbohydrate such as sugar cane juice; 0030; 0055), (ii) fermenting said feedstock with a Clostridia class bacterium which natively produces butyric acid (Fig. 2; 0031; 0055, which uses Clostridium tyrobutryricum as an example), while maintaining a pH of about 5 to 7 (0033, which teaches a pH of 5.5-6.5; 0055, which teaches using ammonia to adjust the pH to 6, and whereby a fermentation broth is formed comprising ammonium butyrate (Fig. 2; 0029; 0033), biomass and a fermentation byproduct (0055-0057, the fermentation produces both butyric acid and acetic acid, thus given that the ammonia is present in the broth, the acetic acid necessarily exists as ammonium acetate); (iii) separating said biomass from said fermentation broth to form separated biomass and a clarified fermentation broth (0056), wherein said clarified fermentation broth comprises said ammonium butyrate and said fermentation byproduct (0056); and (iv) adding to said clarified broth a mineral acid (e.g., an inorganic acid such as sulfuric acid, 0017; 0058; Fig. 2), whereby said butyrate product (e.g., butyric acid, 0017) and an ammonium salt (for example ammonium sulfate. Fig. 2; 0036) are formed in said clarified broth. Kang further teaches separating butyric acid in free acid form from said clarified broth by liquid-liquid extraction (e.g., solvent extraction, 0017; 0059-0060; Fig. 2-3). Kang further teaches providing a alkanol (e.g., C1-C4 alcohol), reacting the butyric acid in free acid form with the alkanol to form a butyrate ester (0017; Fig. 2; 0053), and separating the ester by distillation (0049; 0081).
Kang teaches a method of producing butyric acid comprising fermenting a feedstock that comprises carbohydrate with a Clostridia class bacterium such as Clostridium tyrobutryricum followed by clarification to form a fermentation broth, but is silent regarding at least partially removing water from the clarified fermentation broth to obtain a concentrated fermentation broth.
In the same field of endeavor, Tong teaches a method of preparing a feedstuff comprising butyric acid and/or butyrate, comprising fermenting a feedstock that comprises carbohydrate (e.g., light corn steepwater) with a Clostridia class bacterium such as Clostridium tyrobutryricum to form a fermentation broth, followed by subjecting the fermentation broth to evaporation-condensation so as to increase the concentration of butyric acid through the evaporation of water (0009; 0021; 0036; 0077-0079).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Kang by including the step of evaporation-condensation after fermentation but prior to extraction so as to increase the concentration of butyric acid. The action of evaporation-condensation reads on the limitation about at least removing water from the (clarified) fermentation broth.
Kang as recited above teaches a clarified and spent fermentation broth that comprises ammonium sulfate (0036; Fig. 2), but is silent regarding reacting ammonium sulfate with a calcium base to liberate ammonia and form a precipitate of calcium sulfate, and reusing the liberated ammonia for pH control in the fermentation. However, Kang expresses the idea of “recovering ammonia from the ammonia salt of the broth to reuse it” (0036). Additionally, Kang teaches that the solvent recovered from esterification reaction of butyric acid with an alcohol can be recycled back to the column used separating butyric acid from the clarified broth by solvent extraction (Fig. 2-3; 0015), establishing the suitability of reusing an ingredient recovered from the downstream step in a upstream step.
Tyson teaches a method of recovering a Friedel-Crafts catalyst, in which ammonium sulfate is produced as a by-product, and the ammonium sulfate can be reacted with calcium hydroxide so as to regenerate ammonia (column 2, line 20-49; column 3, line 26-29).
Both Kang and Tyson are directed to processes that result in a by-product that comprises ammonium sulfate. It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Kang by subjecting the broth that comprises ammonium sulfate to a reaction with calcium hydroxide so as to regenerate ammonia. Reaction of ammonium sulfate with calcium hydroxide in an aqueous environment necessarily forms calcium sulfate as a precipitate, beside the liberation of ammonia (e.g., (NH4)2SO4 + Ca(OH)2 → CaSO4 + 2NH3 + 2H2O).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have reused the ammonia liberated from the reaction of ammonium sulfate with calcium hydroxide for pH control in the fermentation step, since Kang expresses the idea of “recovering ammonia from the ammonia salt of the broth to reuse it”, and that Kang has established the suitability of reusing an ingredient recovered from the downstream step in a upstream step.
Regarding claim 11, the language “said butyrate is a feed ingredient” is not considered to further limit the said butyrate. It is the examiner’s position that the intended use recited in the present claims do not result in a structural difference between the presently claimed butyrate (e.g., butyric acid) and the prior art butyric acid and further that the butyric acid of the prior art is capable of performing the intended uses. Given that Kang in view of Tong and Tyson teaches the same method as the claimed method and the method of Kang in view of Tong and Tyson results in a same product as the claimed invention (e.g., butyric acid)., it is clear that the butyric acid as disclosed by prior art would be capable of performing the intended use, i.e., as a feed ingredient.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Kang in view of Tong and Tyson as applied to claim 1 above, and further in view of Belsky US Patent No. 4,349,418 (hereinafter referred to as Belsky).
Regarding claim 15, Kang as recited above teaches a clarified and spent fermentation broth that comprises ammonium sulfate (0036; Fig. 2), but is silent regarding crystallizing ammonium sulfate from the broth.
Belsky teaches that a coal tar extraction process results in a by-product which is an aqueous stream that comprises ammonium sulfate, wherein crystallization can be applied to recover ammonium sulfate which is useful as a fertilizer (column 4, line 4-22).
Both Kang and Belsky are directed to extraction processes that result in a by-product which is an aqueous stream that comprises ammonium sulfate. It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Kang by subjecting the clarified and spent fermentation broth comprising ammonium sulfate to a crystallization process for the benefit of recovering ammonium sulfate for fertilizer use.
Claims 1, 10-11 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Sevenier WO 2019/068642 A1 (cited in the IDS submitted 09/18/2024, hereinafter referred to as Sevenier) in view of Kang US Patent Application Publication No. 2013/0164801 A1 (hereinafter referred to as Kang), Tong US Patent Application Publication No. 2018/0125092 A1 (hereinafter referred to as Tong) and Tyson US Patent No. 3,026,176 (hereinafter referred to as Tyson).
Regarding claims 1 and 16, Sevenier teaches a method for manufacturing a butyrate product (Abstract; page 3, line 24- page 4 line 15), comprising (i) providing a carbohydrate-comprising fermentation feedstock (page 11, line 26-32), (ii) fermenting said feedstock with a Clostridia class bacterium which natively produces butyric acid (page 7, line 28-35; page 10, line 32-33), while maintaining the pH at a sufficient level through using ammonia (page 16, line 1-3) and whereby necessarily a fermentation broth is formed comprising ammonium butyrate formed by the reaction of butyric acid with ammonia, biomass and a fermentation byproduct (page 27, Table 2); (iii) separating said biomass from said fermentation broth to form separated biomass and a clarified fermentation broth (page 13, line 25-30; page 27, Table 2), wherein said clarified fermentation broth necessarily comprises said ammonium butyrate and said fermentation byproduct; and (iv) adding to said clarified broth a mineral acid (e.g., sulfuric acid, phosphoric acid or nitric acid, page 14, line 4-7) such that the pH of the clarified broth is below the pKa of the butyric acid (page 13, line 31-33), whereby necessarily butyric acid and an ammonium salt are formed in said clarified broth (at a pH that is below the pKa of butyric acid, the butyrate will exist in free acid form, and a mineral acid such as sulfuric acid will react with ammonium cation present in the broth to form ammonium sulfate). Sevenier further teaches separating butyric acid from the clarified broth by distillation (page 16, line 12-17).
Sevenier teaches that during fermentation, the produced organic acids accumulate in the fermentation medium which will negatively affect the growth of the microorganism, thus ammonia is added to the fermentation medium to maintain the pH at a sufficient level to permit the continued growth of microorganism (the para. that bridges pages 16 and 17). Sevenier is silent regarding the pH during the fermentation.
In the same field of endeavor, Kang teaches a method of producing butyric acid through fermentation with a Clostridia class bacterium (0017; 0031). Kang further teaches that butyric acid in the broth produced from the butyric acid production strain is provided in the form of a butyrate salt coupled with a monovalent or divalent cation, rather than the form of a free acid. This is because the activity of microorganisms may be lowered when pH of the broth decreases due to accumulation of butyric acid in the broth, and thus a basic material is typically added to uniformly maintain pH of the broth. Accordingly, butyric acid of the broth is provided in the form of a butyrate salt coupled with a cation, for example, ammonia to form ammonium butyrate or calcium butyrate coupled with a monovalent or divalent cation, but is not limited thereto, and may further include any inorganic material typically used to adjust pH depending on predetermined purposes. The pH of the broth may be 4 to 6.5, and preferably 5.5 to 6.5 (0033; 0055).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Sevenier by adjusting the pH of the fermentation medium to 5.5-6.5 with reasonable expectation of success, for the reason that prior art has established that such a pH range is suitable in growing Clostridia class bacterium that could produce butyric acid.
Sevenier teaches a method of producing butyric acid comprising fermenting a feedstock that comprises carbohydrate with a Clostridia class bacterium followed by clarification to form a fermentation broth, but is silent regarding at least partially removing water from the clarified fermentation broth to obtain a concentrated fermentation broth.
In the same field of endeavor, Tong teaches a method of preparing a feedstuff comprising butyric acid and/or butyrate, comprising fermenting a feedstock that comprises carbohydrate (e.g., light corn steepwater) with a Clostridia class bacterium to form a fermentation broth, followed by subjecting the fermentation broth to evaporation-condensation so as to increase the concentration of butyric acid through the evaporation of water (0009; 0021; 0036; 0077-0079).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Sevenier by including the step of evaporation-condensation after fermentation but before distillation so as to increase the concentration of butyric acid. The action of evaporation condensation reads on the limitation about at least removing water from the (clarified) fermentation broth.
Sevenier as recited above teaches a fermentation broth that comprises ammonium sulfate, but is silent regarding reacting ammonium sulfate with a calcium base to liberate ammonia and form a precipitate of calcium sulfate, and reusing the liberated ammonia for pH control in said fermentation. However, Kang expresses the idea of “recovering ammonia from the ammonia salt of the broth to reuse it” (0036). Additionally, Kang teaches that the solvent recovered from esterification reaction of butyric acid with an alcohol can be recycled back to the column used separating butyric acid from the clarified broth by solvent extraction (Fig. 2-3; 0015), establishing the suitability of reusing an ingredient recovered from the downstream step in a upstream step.
Tyson teaches a method of recovering a Friedel-Crafts catalyst, in which ammonium sulfate is produced as a by-product, and the ammonium sulfate can be reacted with calcium hydroxide so as to regenerate ammonia (column 2, line 20-49; column 3, line 26-29).
Both Sevenier and Tyson are directed to a process that results in a by-product that comprises ammonium sulfate. It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Sevenier by subjecting the broth that comprises ammonium sulfate to a reaction with calcium hydroxide so as to regenerate ammonia. Reaction of ammonium sulfate with calcium hydroxide in an aqueous environment necessarily forms calcium sulfate as a precipitate, beside the liberation of ammonia (e.g., (NH4)2SO4 + Ca(OH)2 → CaSO4 + 2NH3 + 2H2O).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have reused the ammonia liberated from the reaction of ammonium sulfate with calcium hydroxide for pH control in the fermentation step, since Kang expresses the idea of “recovering ammonia from the ammonia salt of the broth to reuse it”, and that Kang has established the suitability of reusing an ingredient recovered from the downstream step in a upstream step.
Regarding claim 10, Sevenier teaches acetic acid is formed (page 27, Table 2), which will necessarily react with ammonia present in the fermentation medium to form ammonium acetate.
Regarding claim 11, Sevenier teaches that butyric acid is a feed ingredient (page 1, line 22-26).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Sevenier in view of Kang, and Tong and Tyson as applied to claim 1 above, and further in view of Belsky US Patent No. 4,349,418 (hereinafter referred to as Belsky).
Regarding claim 15, Sevenier as recited above teaches a fermentation broth that comprises ammonium sulfate, but is silent regarding crystallizing ammonium sulfate from the broth.
Belsky teaches that a coal tar extraction process results in a by-product which is an aqueous stream that comprises ammonium sulfate, wherein crystallization can be used to recover ammonium sulfate which is useful as a fertilizer (column 4, line 4-22).
Both Sevenier and Belsky are directed to an aqueous stream that comprises ammonium sulfate. It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to have modified Sevenier by subjecting the fermentation broth comprising ammonium sulfate to a crystallization process for the benefit of recovering ammonium sulfate for fertilizer use.
Response to Arguments
Applicant's arguments filed 04/27/2025 have been fully considered and the examiner’s response is shown below:
The 35 USC 112(b) rejection is withdrawn, in view of the amendment made to claim 1.
Regarding the limitation about reusing the regenerated ammonia in previously presented claim 32 (e.g., currently claim 1) and the examiner’s allegation that prior art has established the suitability of reusing an ingredient recovered from the downstream step in an upstream step since Kang teaches that the solvent recovered from esterification reaction of butyric acid with an alcohol can be recycled back to the column used for separating butyric acid from the clarified broth by solvent extraction, applicant argues on page 7 of the Remarks that recovery of a solvent from esterification reaction of butyric acid with an alcohol and recycling back to a column used separating butyric acid from clarified broth by solvent extraction is significantly different from recycling a regenerated reagent, such as ammonia. Applicant goes on to argue that the overall process as claimed converts a fermentable feedstock into a purified, isolated concentrated acid or ester thereof, via three different acid-base reactions (e.g., reaction of ammonia with butyric acid to produces ammonium butyrate, reaction of ammonium butyrate with a mineral acid to product free butyric acid, and reaction of ammonium with lime to liberate ammonia), however, such an overall process is not taught or suggested by the cited references alone or in combination.
The arguments are considered. They are not persuasive because:
First, although the recovery of a solvent from esterification reaction and recycling back to a column is different from recycling ammonia in a technical manner, the concept of recycling is the same. In other words, the knowledge that in a chemical process an ingredient or substance recovered from the downstream step can be reused in a upstream step is sufficient to motivate the skilled person to reuse the ammonia recovered from reacting ammonium sulfate with lime in the step of adjusting pH of the fermentation stock. After all, it does not appear that the ammonia used to adjust pH as disclosed by Kang is materially different from the ammonia recovered from reacting ammonium sulfate with lime.
More importantly, Kang expresses the idea of “recovering ammonia from the ammonia salt of the broth to reuse it” (0036). Such an expression would have motivated one of ordinary skill in the art to reuse the liberated ammonia in the pH adjustment step.
Second, the overall process of converting a fermentable feedstock into a purified, isolated concentrated acid or ester thereof via three different acid-base reactions is met by Kang, Tong and Tyson. For example, Kang teaches converting a fermentable feedstock into free and isolated butyric acid or ester thereof (see para. 11 of the OA issued 01/28/2026), Tong teaches the step of concentrating thus Kang in view of Tong teaches isolated concentrated butyric acid or ester thereof ( see para. 13-14 of the OA issued 01/28/2026). Further Kang, Tong and Tyson teaches the three different acid base reactions. For example, Kang teaches adding ammonium to the fermentation feedstock which produces free butyric acid (see Fig 2 of Kang), which is actually the reaction of ammonia with butyric acid to produces ammonium butyrate; Kang teaches adding a mineral acid (e.g., sulfuric acid) to the fermentation broth that comprises ammonium butyrate (see Fig. 2 of Kang), which is the reaction of ammonium butyrate with a sulfuric acid to product free butyric acid and ammonium sulfate; and Kang as modified by Tyson teaches reacting the ammonium sulfate with lime (e.g., calcium hydroxide) (see Tyson column 3, line 26-29), which liberates ammonia (see Tyson column 3, line 26-29).
For the reason set forth above, applicant’s argument on page 8 of the Remarks regarding Sevenier in view of Kang, Tong and Tyson is not persuasive, either.
Conclusion
Pertinent art
The prior art made of record and not relied upon is considered pertinent to applicant’s disclosure
Kim KR101094447B1, which teaches a step of manufacturing butyric acid comprising providing a carbon-source-containing fermentation feedstock, adjusting the pH of the feedstock with ammonia to a pH of 5.8-6.5, fermenting the feedstock with a Clostridia bacteria to form ammonia butyrate and a byproduct, separating a biomass from the ammonium butyrate and byproduct; concentrating to obtain a clarified fermentation broth, and acidifying the clarified fermentation broth to obtain free butyric acid.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHANGQING LI whose telephone number is (571)272-2334. The examiner can normally be reached 9:00-5:00.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, NIKKI H DEES can be reached at 571-270-3435. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CHANGQING LI/Primary Examiner, Art Unit 1791
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