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 .
Claim Status
Claims 1, 3, and 10-16 were amended and claims 4-8 and 17 were canceled in the response filed on 8/7/2026. Claims 1-3, 9-16, and 18 are pending and under examination.
Withdrawn Objections and Rejections
The drawings and amended specification were received on 8/7/2026. Both are acceptable, therefore the objections of record on p. 2-3 of the OA dated 5/18/2026 are withdrawn.
The claim amendments are persuasive to overcome the objections of record on p. 3-4 of the OA dated 5/18/2026. Therefore, the objections are withdrawn.
The claim amendments also removed any indefinite language from the claims; therefore the 35 USC 112(b) rejections of record on p. 4-7 of the OA dated 5/18/2026 are withdrawn.
The Applicant canceled claims 4-6 and incorporated their limitations into independent claim 1. Claims 4-6 were not included in the 35 USC 102 rejection of record over Shima (US3668221, published on 6/6/1972) on p. 7-9 of the OA dated 5/18/2026; therefore, the rejection of record is withdrawn.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. See p. 9-14 of the OA dated 5/18/2026 for the rejections of record.
Claim(s) 1, 2, and 9-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shima (US3668221, published on 6/6/1972, of record) as evidenced by the CAS SciFinder® entry for sodium hydroxide (1310-73-2), downloaded on 5/7/2026, of record) and Gorak (“Distillation Equipment and Processes: Ch. 8 Reactive Distillation” p. 261, published 2014, of record).
Shima teaches a process for producing an alpha-amino acid by hydrolyzing a hydantoin compound in which the hydrolysis is effected while withdrawing out of the system ammonia and carbon dioxide generated during the hydrolysis and while during the reaction period, adjusting the amount of reaction medium to at least 1.5 liters per mole of the hydantoin compound initially employed. Particularly, a process in which the hydrolysis is effected in such a manner that an aqueous alkaline solution of hydantoin compound is fed to the upper part of a plate column-type reactor or packed column-type reactor and, simultaneously, steam is fed from the lower part of said reactor, while withdrawing ammonia and carbon dioxide out of the system. By thus effecting the hydrolysis without concentrating the reaction liquid, and while withdrawing the generated gases out of the system, alpha-amino acid can be produced in high yields See abstract and claims. Shima teaches examples 1-3 in col. 4-5 for the hydrolysis of 5-(2’-methylthioethyl)hydantoin, the compound of instant formula 1, in the presence of aqueous caustic soda (sodium hydroxide-see “other names for this substance” in CAS® evidentiary reference) between 160-180°C (claim 12) to produce the sodium (alkali) metal salt of methionine (claims 9 and 10). The examples also teach continuously withdrawing the generated ammonia and carbon dioxide from the reactor by stripping with steam. Example 1 is carried out in an autoclave, Example 2 is carried out in a bubble cap column reactor or plate column reactor, and Example 3 is carried out in column reactor packed with Raschig rings (a reactive stripping packed column). Also see Fig. 2 and discussion thereof in col. 3, line 36-col. 4, line 27. Therefore, example 3 of Shima meets all of the limitations of instant claim 1. See MPEP 2131.
Further regarding claim 2, all packings are either random or structured, such that the Raschig rings must necessarily meet the limitations of the claim. Regardless, Gorak is cited as an evidentiary reference that shows that Raschig rings are considered as random packings. See Figure. 8.8 on p. 277. Regarding claim 11, example 1 teaches that the hydantoin is formed in situ such that precursors of the hydantoin are presumed to be present. Further regarding claim 14, the retention time of the liquid in the column is 1.34 hours, which is greater than 1 minute.
Regarding claim 1, Shima does not explicitly teach that the reactive stripping column is coupled with two or more additional reactors. However, Shima teaches that the hydrolysis yield of the inventive examples in col. 4-5 was below 100%, falling within the range of 89.5 to 96.1%. Thus, there is room for improvement in Shima. Shima further teaches that gas stream of ammonia and carbon dioxide obtained from the top of the reactive stripping column are rectified to liquefy and separate the reaction medium accompanied therewith and thus liquefied and separated medium is refluxed to the hydrolysis reaction system. Shima further teaches that the reactive stripping column can comprise packed columns and plate columns, such as bubble cap columns or perforated plate columns.
Regarding claims 13 and 15, Shima teaches that the residence time for the hydrolysis may fall within the range of 10-120 minutes and within the pressure range of 1.8-27 kg/cm2 (about 1.8-27 bar). See col. 2, lines 27-38. Both of these ranges overlap with the claimed ranges. Also see MPEP 2144.05.
Regarding claim 16, Shima teaches that the liquid hydrolysis product containing an alkali salt of the alpha-amino acid (sodium methionine salt) in line 11 of fig. 2 can be neutralized with an acid to obtain the alpha-amino acid (methionine). See lines 25-27 of col. 4 and Fig. 2.
It would have been prima facie obvious to arrive at the instantly claimed process based on the teachings of Shima with a reasonable expectation of success before the effective filing date of the claimed invention. A person of ordinary skill would have been motivated to include another reactor/column in the hydrolysis process of Shima in order to increase the conversion in the hydrolysis reaction from 89.5-96% to 100%, thus increasing the output of the reaction. Further, Shima teaches that the reactive packed column can comprise a reflux recycle line to return hydrolysis liquid to column for further reaction. This is analogous to feeding to the hydrolysis liquid to a second reactor. A person of ordinary skill would have been motivated to select another reactive stripping column comprising packing, plates, or bubbles, because Shima teaches that are all acceptable equivalents in the disclosed process. Further, if the conversion of the hydrolysis reaction is as high as 89.5-96.1% exiting the first reaction stripping column, then if the second reactor is the same type of column, an equally high yield would be predictably expected from the second reactor.
A person of ordinary skill would have been further motivated to carry out the hydrolysis reaction in the claimed pressure and residence time ranges because Shima teaches ranges which overlap with those claimed. Also see MPEP 2144.05.
A person of ordinary skill would have been further motivated to neutralize the sodium salt of methionine at the end of the hydrolysis reaction to obtain methionine, because such is explicitly suggested by Shima.
Claim(s) 3 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Shima (US3668221, published on 6/6/1972, of record) as evidenced by the CAS SciFinder® entry for sodium hydroxide (1310-73-2), downloaded on 5/7/2026, of record) and Gorak (“Distillation Equipment and Processes: Ch. 8 Reactive Distillation” p. 261, published 2014, of record), as applied to claims 1, 2, and 9-16 above, and further in view of Geiger (US 5770769, published on 6/23/1998, of record).
The Applicant claims a process wherein the packings of the reactive stripping packed column are made of one or several materials selected from metals and stainless and corrosion-resistant metal alloys, plastics, or ceramics (claim 3) and wherein the neutralization is performed in the presence of CO2 (claim 18).
Shima fails to explicitly teach any of the above limitations.
Geiger is directed toward an analogous process for the hydrolysis of 5-(2-methylmercaptoethyl)-hydantoin to obtain methionine. See abstract. Geiger teaches that the hydantoin is hydrolyzed in a basic aqueous medium to produce the alkali metal salt of methionine, which is then neutralized in the presence of carbon dioxide (claim 18). See examples 6-7 in col. 13-14 and col. 8, line 25-col. 11, line 5. Geiger teaches that the hydrolysis reactor comprises zirconium or a zirconium alloy fitting because zirconium has a favorable effect on the hydrolysis and is high resistant and durable. See col. 8, lines 42-44; col. 9, lines 8-16; and col. 10, lines 33-48. Geiger also teaches that the neutralization reaction is carried out in continuous stirred tank reactor. See col. 11, lines 1-5 and example 7.
It would have been prima facie obvious to combine the teachings of Shima and Geiger to arrive at the instantly claimed process with a reasonable expectation of success before the effective filing date of the claimed invention. A person of ordinary skill would have been motivated to use corrosion-resistant zirconium alloys for any/all parts of the reactive stripping column of Shima because Geiger teaches that said metals are resistant and durable to the hydrolysis conditions. Thus, the combination would predictably result in a more durable and corrosion-resistant hydrolysis reactive stripping column. Also see MPEP 2143(I)(B).
A person of ordinary skill would have been motivated to include carbon dioxide in the neutralization reaction of Shima because Geiger teaches that this is a known, predictable, and well-functioning reaction to obtain methionine which uses one of the by-products from the hydrolysis reaction. Therefore, carrying out the neutralization reaction under known and predictably conditions is not inventive. Also see MPEP 2143(I)(A).
Response to Arguments on p. 9-12 of the response filed 8/7/2026
Applicant argues that Sima does not explicitly teach that the method is carried out “first in a reactive stripping packed column and then in at least one reactor selected from reactive stripping plate columns.” Applicant argues that this limitation is not obvious in view of the teaching of Shima and is not cured by any of the evidentiary or secondary references cited. Applicant claims that the inventive method unexpectedly optimizes yield of the hydrolysis reaction and selectivity for methionine (or selenomethionine) salt. Applicant argues that this is supported by the superior results of inventive Example 2 over those of comparative Example 1.
The Applicant’s arguments have been fully considered but are not persuasive. While the Examiner acknowledges that Shima does not explicitly teach the claimed limitation, the Examiner respectfully disagrees that there is not motivation to arrive at the claimed process based on the teachings of Shima. As discussed in the rejection:
“Regarding claim 1, Shima does not explicitly teach that the reactive stripping column is coupled with two or more additional reactors. However, Shima teaches that the hydrolysis yield of the inventive examples in col. 4-5 was below 100%, falling within the range of 89.5 to 96.1%. Thus, there is room for improvement in Shima. Shima further teaches that gas stream of ammonia and carbon dioxide obtained from the top of the reactive stripping column are rectified to liquefy and separate the reaction medium accompanied therewith and thus liquefied and separated medium is refluxed to the hydrolysis reaction system. Shima further teaches that the reactive stripping column can comprise packed columns and plate columns, such as bubble cap columns or perforated plate columns.
…
It would have been prima facie obvious to arrive at the instantly claimed process based on the teachings of Shima with a reasonable expectation of success before the effective filing date of the claimed invention. A person of ordinary skill would have been motivated to include another reactor/column in the hydrolysis process of Shima in order to increase the conversion in the hydrolysis reaction from 89.5-96% to 100%, thus increasing the output of the reaction. Further, Shima teaches that the reactive packed column can comprise a reflux recycle line to return hydrolysis liquid to column for further reaction. This is analogous to feeding to the hydrolysis liquid to a second reactor. A person of ordinary skill would have been motivated to select another reactive stripping column comprising packing, plates, or bubbles, because Shima teaches that are all acceptable equivalents in the disclosed process. Further, if the conversion of the hydrolysis reaction is as high as 89.5-96.1% exiting the first reaction stripping column, then if the second reactor is the same type of column, an equally high yield would be predictably expected from the second reactor.”
The Applicant has not addressed why this rationale is deficient. Regarding Applicant’s allegations of unexpected results, though example 2 does provide better results (conversion of 99.5% with a selectivity of 96.5%) than comparative example 1 (conversion of 99%, with a selectivity of 96% for methionine salts), the difference is not significant nor unexpected. The conversions and selectivity differ only by 0.5% and comparative example 1 uses only one reactor while inventive example 2 uses two reactors. Therefore, it would be expected that the process using two reactors in series would produce higher yields and selectivities of the claimed product because whatever has not reacted in the first reactor is given a second opportunity to react in the second reactor. Further, comparative example 1 is directed toward the use of one reactive stripping plate column, while Example 3 of Shima is carried out in column reactor packed with Raschig rings (a reactive stripping packed column). Therefore, the comparative result is not analogous with example 3 of Shima, which is the closest prior art to the claimed invention. Additionally, though the Applicant argues that example 2 falls within the scope of claim 1 (which requires first reaction in a packed column and second reaction in a plate column), the text of example 2 indicates “reactive stripping plate column then packed column”, which is the reverse of the claimed order (also see instant Fig. 5, which teaches the same). Therefore, the claimed process is also not commensurate in scope with the claimed invention. Also see MPEP 2145. The rejections are maintained for the reasons of record.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AMY C BONAPARTE whose telephone number is (571)272-7307. The examiner can normally be reached 11-7.
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/AMY C BONAPARTE/Primary Examiner, Art Unit 1692
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