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 in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 May 11, 2026 has been entered.
DETAILED ACTION
3. Claims 1 – 9, 13 – 17, and 21 – 23 are pending in this application, wherein claim 3 is amended and claims 10 – 12 and 18 – 20 are canceled.
Claims 1 – 9, 13- 17, and 21 – 23 are examined on the merits herein.
Priority
This application is a national stage application of PCT/KR2019/016668, filed November 29, 2019, which claims benefit of foreign priority document KR10-2018-0152876, filed November 30, 2018; this foreign priority document is not in English.
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Should applicant desire to obtain the benefit of foreign priority under 35 U.S.C. 119(a)-(d) prior to declaration of an interference, a certified English translation of the foreign application must be submitted in reply to this action. 37 CFR 41.154(b) and 41.202(e).
Failure to provide a certified translation may result in no benefit being accorded for the non-English application is only pertinent when interference arises.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1 – 2, 8 – 9, 17, and 23 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
a. Claims 1, 8 – 9, 17, and 23 recite “(w/w)”. The phrase is written within a parenthesis. It is unclear whether the parenthetical phrase is limiting and it intended to define the concentration or is merely providing non-limiting descriptive information. Thus, the metes and bounds of the claims are not clear and the phrase renders the claims indefinite. Claim 2 depends from claim 1 and is, therefore, indefinite.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
i. Determining the scope and contents of the prior art.
ii. Ascertaining the differences between the prior art and the claims at issue.
iii. Resolving the level of ordinary skill in the pertinent art.
iv. Considering objective evidence present in the application indicating obviousness or
nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 3 – 5, 8 – 9, 13 – 17, and 21 – 23 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (US8524888B2, cited in the PTO-892 on June 12, 2025) in view of Muller (Anti-solvent crystallization of sucrose, 2016, cited in the PTO-892 on December 9, 2025), Giulietti (InTech EBooks, 2012, cited in the PTO-892 on January 26, 2024), and ICH (ICH Harmonised Guideline, 2016, cited in the PTO-892 on December 9, 2025).
Lee et al. teach a method of producing purified D-psicose crystals, wherein the method comprises concentrating a purified D-psicose solution and crystallizing D-psicose from the concentrated D-psicose solution (Col. 4, lines 9 – 11; lines 26 – 30). In example 7, a D-psicose solution purified as described in example 3 is obtained, wherein Lee et al. teach that the D-psicose solution purified in example 3 is obtained using deionized water as the eluent and mobile phase during purification (Col. 7, lines 17 – 18). The D-psicose solution purified according to example 3 is then concentrated to about 85% (g/g solution) (Col. 8, lines 51 – 54). Therefore, the concentrated D-psicose solution of example 7 would have been understood by one of ordinary skill in the art to be an aqueous D-psicose solution. Then, D-psicose seeds are mixed with ethanol to prepare a D-psicose solution. The D-psicose ethanol solution is introduced as a seed to the concentrated D-psicose solution in the crystallizer (Col. 8, lines 55 – 58). D-psicose seeds may be added to the concentrated D-psicose solution used in the crystallizing in an amount of D-psicose is about 0.01% to about 1% (g/g) based on the total amount of D-psicose dissolved in the concentrated D-psicose solution (Col. 4, lines 34 – 37). The disclosure read on the limitations “mixing D-psicose-containing solution and an ethanol” “thereby producing a mixed solution” of claim 3 because the concentrated D-psicose solution is an aqueous D-psicose solution and the crystallization mixture contains D-psicose, water, and ethanol after introduction of the D-psicose ethanol seed solution. The disclosure read on the limitation “adding a seed to the mixed solution” of claim 3 because the D-psicose ethanol solution that is introduced to the concentrated D-psicose solution contains D-psicose seeds. The disclosure also encompass the limitation of claim 23.
Said crystallizer is controlled to maintain the temperature at about 50 ⁰C (Col. 8, lines 54 – 55). To produce D-psicose crystals, the D-psicose solution needs to be in a supersaturated stated under a metastable zone, wherein the supersaturated state may be maintained by lowering the temperature or by controlling the temperature of a D-psicose solution (Col. 4, lines 28 – 30; lines 39 – 41; lines 44 – 47). When the temperature reaches a point (saturation temperature) at which a change in crystal size or a change in concentration of a supernatant did not occur any more, the temperature of the crystallizer is cooled down by about 1 ⁰C so that the D-psicose solution would exist in a zone between its saturation concentration and is supersaturation concentration, that is a supersaturated state under a metastable zone be maintained (Col. 9, lines 3 – 10). Thus, Lee et al. teach cooling the D-psicose solution to facilitate the formation of D-psicose crystal, which correspond to “cooling the same to obtain a massecuite containing the D-psicose crystal” and “the seed is grown in a metastable zone by adjusting a cooling rate” of claims 3 and 5, respectively. Lee et al. teach the temperature in the crystallizer, which reads on the limitation “mixing in the first step is performed at 40 ⁰C to 60 ⁰C” of claim 4.
In an embodiment, the concentrated D-psicose solution used in the crystallizing may be a D-psicose solution of about 70% to about 85% or more (Col. 4, lines 31 – 33). Because “85% or more” includes concentrations greater than 85%, including the claimed 95%, Lee et al. teach or suggest a D-psicose-containing solution containing 95% w/w or more D-psicose as recited in claim 8.
The concentration of the D-psicose solution used in the crystallizing is about 70% (g/g) or more (claim 4), which encompasses the limitation of claims 13 and 21.
Lee et al. teach that the D-psicose crystals recovered after the dehydration is transferred to a fluidizer bed dryer or a vacuum dryer for drying (Col. 9, lines 26 – 28). Thus, Lee et al. teach that the D-psicose crystals are being separated and dried from the massecuite, which reads on the limitation of the third step in claim 14.
However, Lee et al. do not explicitly teach the ratio of water to ethanol is 1:0.5 or more and the final temperature. Lee et al. do not teach that the finally obtained D-psicose crystal has a weight percentage of 65% (w/w) or more compared to the D-psicose content existing in the D-psicose-containing solution in the first step. Lee et al. also do not teach a step of recovering the ethanol and reusing the recovered ethanol and reusing the crystal mother liquor after removing the ethanol. Finally, Lee et al. do not teach to adjust the concentration of ethanol in the D-psicose crystal to 0.05% (w/w) or less.
Muller discloses crystallization of sugar, wherein anti-solvent crystallization is discussed (Abstract). Anti-solvent crystallization involves adding an additional substance, called the anti-solvent, which induces crystallization. Anti-solvent crystallization achieves supersaturation by exposing a solution of the product to another solvent in which the product is poorly soluble. The anti-solvent must be miscible with the solvent and must change the solubility of the solute in the solvent. For example, if the solvent is ethanol, the anti-solvent might be water (page 12, para. 1). Pharmaceutical and fine chemical makers frequently rely on anti-solvent crystallization to generate a solid from a solution in which the produce has high solubility (page 12, para. 2). Thus, Muller teaches that anti-solvent crystallization with ethanol and water may be used to obtain sugar crystal.
Anti-solvent crystallization is represented as (page 12, Figure 2.5):
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In the first section of this schematic representation, the solution is mixed with anti-solvent. Due to the anti-solvent’s ability to bind water, the solubility of the solute is reduced, resulting in the formation of solid phase either by precipitation or by crystallization. Subsequently, in the separation section, the crystals are separated from the mixture either by filtration or centrifugation, leaving a clear filtrate that is sent to the anti-solvent regeneration section, wherein solvent and anti-solvent are separated. Finally, the anti-solvent is recycled to the crystallization section while the water can be used for the dissolution of new material. It is obvious that the use of an anti-solvent yields a crystal product without needing to evaporate the solvent, but still requires a separation step. Solvent (water) and anti-solvent (ethanol) can be separated by simply inducing liquid-liquid phrase separation after which both concentrated phases could be recycled within the process. The most common way of separating ethanol from water is by distillation (page 12, para. 3). The disclosure teaches to remove anti-solvent from the mixture and to reuse it in the crystallization process, which corresponds to the limitations of claim 15.
Moreover, seeding may help avoid excessive nucleation. The seed can be added as a powder or in slurry form with the anti-solvent. Adding seed with the anti-solvent offers an advantage over the traditional method of putting seed in at a single time which poses the risk of adding too soon (seeds dissolve) or too late (nucleation has already occurred) (page 13, para. 2). Therefore, seeding techniques can help produce the desired outcome (page 13, para. 3).
Giulietti teaches that antisolvent crystallization may be combined with cooling strategies to enhance crystallization. In the study of antisolvent cooling crystallization of fructose, Giulietti compares different parameters:
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Table 3 shows that the ethanol to water ratio may be 1 : 1.5, 1 : 4.0, 1 : 6.0, and 1 : 9.0 (page 389, Table 3). The crystals yield is more than 93% of the available fructose quantity for all experiments (page 389, lines 12 – 13). In another embodiment, the ethanol to water ratio used in the crystallization of lactose may be 1 : 1 with the final temperature of 25 ⁰C (page 390, line 9; Table 5)):
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Giulietti also teaches the good choice of antisolvent must be done carefully with preliminary experiments that can allow to obtain high yields and easiness of solvent recovery (page 395, para. 4). However, the ethanol quantity and temperature do not affect the crystal growth rate significantly (page 389, lines 19 – 20). Thus, Giulietti teaches the general ethanol to water ratio used in crystallization of sugar, which reads on the limitation of the first step in claim 3.
ICH discloses a guideline for recommended use of less toxic solvents and the levels considered to be toxicologically acceptable for some residual solvents (page 1, para. 1). Ethanol is classified as Class 3 solvent (page 11) and Class 3 solvents below 0.5% need not be reported (page 4, 3.5 Reporting levels of residual solvents).
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to combine the method of producing purified D-psicose crystals, including concentrating the purified D-psicose solution and crystallizing D-psicose from the concentrated D-psicose solution in a supersaturated state under a metastable zone as taught by Lee et al. with anti-solvent crystallization using water and ethanol in view of Muller because Muller teaches that anti-solvent crystallization has been used to generate a product that has high solubility and a crystal product is yield without need of evaporating the solvent. One would have been motivated to combine the method as taught by Lee et al. with anti-solvent crystallization using water and ethanol in view of Muller because Muller teaches that anti-solvent crystallization is suitable for product with high solubility and it is known in the art that D-psicose is highly soluble. One would have been motivated to combine the method as taught by Lee et al. with anti-solvent crystallization using water and ethanol in view of Muller because Muller teaches that evaporating is not needed in the process, and is, therefore, more energy efficient.
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to combine the method as taught by Lee et al. and Muller with the ethanol to water ratio used in the anti-solvent crystallization of sugar in view of Giulietti because Giulietti teaches that the crystals yield would be 93% or more based on the method. One would have been motivated to combine the method as taught by Lee et al. and Muller with the ethanol to water ratio used in the anti-solvent crystallization of sugar in view of Giulietti because of the improved crystal yield. For the final temperature, one would have performed a routine experimentation to discover the best final temperature for the optimal D-psicose production. Therefore, one of the ordinary skill in the art would have had a reasonable expectation of success to combine the method of producing purified D-psicose crystals, including removing impurities from a D-psicose solution to obtain a purified D-psicose solution, concentrating the purified D-psicose solution, and crystallizing D-psicose from the concentrated D-psicose solution in a supersaturated state under a metastable zone as taught by Lee et al. with anti-solvent crystallization using water and ethanol and the ethanol to water ratio used in the anti-solvent crystallization of sugar in view of Muller and Giulietti as Lee et al. teach a method for producing D-psicose crystals, Muller teaches the benefits of anti-solvent crystallization and Giulietti teaches water-to-ethanol ratio used in anti-solvent crystallization for producing sugar crystals, thereby, the combination will yield predictable results.
Regarding claim 4, Lee et al. teach that crystallization is performed at about 50 ⁰C in the crystallizer, which falls within the claimed mixing temperature range of 40 ⁰C to 60 ⁰C. Lee further teach lowering the crystallizer temperature to maintain the D-psicose solution in a supersaturated state within a metastable zone. Giulietti similarly teaches antisolvent cooling crystallization of sugars using ethanol, wherein the saturation temperature may be between 50.5 ⁰C to 60 ⁰C, and cooling is performed to a lower final temperature, such as 30 ⁰C for fructose and 25 ⁰C for lactose. Thus, Lee et al. and Giulietti both teach controlling temperature and cooling a sugar-containing solution during antisolvent crystallization to obtain crystals. Although neither reference explicitly discloses the claimed final temperature of 10 ⁰C to 20 ⁰C, the prior art demonstrates that the final temperature selected for crystallization is an operating condition that may be adjusted depending on the desired crystallization process. In view of Lee et al. and Giulietti, it would have been obvious for one of ordinary skill in the art to select another suitable final temperature, including a temperature within the claimed range of 10 ⁰C to 20 ⁰C, through routine optimization of known crystallization conditions to maintain the D-psicose solution in supersaturated state within a metastable zone. Regarding claim 9, the recited 65% or greater recovery describes the yield obtained from carrying out the crystallization method, rather than an additional process step. Lee et al. teach recovering D-psicose crystals at about 50 – 53% recovery. Giulietti teaches that antisolvent crystallization of sugars using ethanol/water conditions can provide crystals yields greater than 93% of the available sugar. Thus, one of ordinary skill in the art would have been motivated to apply the antisolvent crystallization conditions taught by Muller and Giulietti to the D-psicose crystallization process of Lee et al. to improve crystal recovery. Obtaining a recovery of 65% or more would have been an expected result of the combined process.
Regarding claim 16, Muller teaches that the remaining clear filtrate after separating the crystals is sent to an antisolvent regeneration section where solvent and antisolvent are separated. Muller further teaches that the antisolvent may be recycled to the crystallization section and that water may be used for dissolution of new material. It would have been obvious for one of ordinary skill in the art to recycle the remaining crystal mother liquor or filtrate after removal of an antisolvent because it is a conventional practice in crystallization process and recycling it improves material recovery, process efficiency, and cost-effectiveness.
Regarding claim 17, it would have been prima facie obvious for a person of ordinary skill to adjust the ethanol concentration remaining in the D-psicose crystals to a low residual amount, including within the claimed range of 0.05% (w/w) or less by drying because Lee et al teach drying the ed D-psicose crystals using a fluidized bed dry or vacuum drying and ICH teaches that ethanol is a Class 3 solvent for which low residual amounts are considered acceptable. One of ordinary skill in the art would have recognized that drying is a conventional technique for reducing residual solvent content in a crystalline product and would have been motivated to reduce residual ethanol in the final D-psicose crystal to a low level to improve product quality, reduce residual solvent, and provide a crystal suitable for food or pharmaceutical use. The claimed upper limit of 0.05% is below the ICH reporting threshold of 0.5% for Class 3 solvents and would have been an obvious range obtained by routine drying optimization. One of ordinary skill in the art would have had a reasonable expectation in reducing the ethanol concentration in the D-psicose crystal to 0.05% (w/w) or less because Lee et al. already teach drying the recovered crystals using drying equipment, such as fluidized bed dryer or vacuum dryer. Drying is a well-known process for removing volatile solvents, including ethanol, from crystalline products. Since ethanol is volatile and routinely removed by drying, one of ordinary skill in the art would have expected that the drying of Lee et al. would successfully reduce the residual ethanol content in the final crystal product to a low level that is within the limit disclosed by ICH, including 0.05% (w/w) or less.
Claims 1 – 2 and 6 – 7 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (US8524888B2, cited in the PTO-892 on June 12, 2025) in view of Muller (Anti-solvent crystallization of sucrose, 2016, cited in the PTO-892 on December 9, 2025), Giulietti (InTech EBooks, 2012, cited in the PTO-892 on January 26, 2024), and ICH (ICH Harmonised Guideline, 2016, cited in the PTO-892 on December 9, 2025) as applied to claims 3 – 5, 8 – 9, 13 – 17, and 21 – 23 above, and further in view of Kim et al. (EP3210478A1, cited in the PTO-892 on June 12, 2025).
c. Lee et al., Muller, Giulietti, and ICH teach the limitations discussed above. Lee et al. further disclose that the amount of D-psicose crystals after the drying is about 1408 g, which is about 50% recovery (Col. 9, lines 28 – 31). In another example, the amount of crystals after drying was about 2,650 g, about 53% recovery compared to about 5,000 g of D-psicose which had been dissolved (Col. 10, lines 11 – 14). The crystal size ranges between 0.1 mm and about 0.2 mm (Col. 9, lines 31 – 32; Col. 10, lines 14 – 15). According to the instant specification, the claimed “mean particle size” represents the mean size of the crystal. Thus, Lee et al. teach D-psicose crystals having a crystal size of about 0.1 mm to about 0.2 mm (100 – 200 μm), which corresponds to the claimed particle size measurement of claim 2. However, Lee et al., Muller, Giulietti, and ICH do not teach a D-psicose crystal comprising 98% w/w or more D-psicose based on 100% w/w of the entire crystal. Lee et al., Muller, Giulietti, and ICH do not teach the cooling rate used in the second step is 0.05 ⁰C/hour to 1.4 ⁰C/hour. Lee et al., Muller, Giulietti, and ICH also do not teach the cooling and the crystallization in the second step are performed for 20 hours to 70 hours.
Kim et al. teach a method for producing high purity D-psicose crystals comprising removing impurities from D-psicose solution to obtain a purified D-psicose solution; concentrating the purified D-psicose solution; cooling the concentrated D-psicose solution to 30 ⁰C to 40 ⁰C through a heat exchange; seed crystallizing the D-psicose solution at 30 ⁰C to 40 ⁰C to obtain massecuite; and full-scale crystallizing the seed crystallized massecuite (para. [0017]). The D-psicose solution having a purity of 95% (w/w) in the crystallization device is cooled to 50 ⁰C to 35 ⁰C at a rate of 0.31 ⁰C per hour for 48 hours to perform crystallization (para. [0042]). The D-psicose crystals obtained have a purity of 98% (w/w) or more and a grain size of MA200 or more (Abstract). Thus, Kim et al. teach the cooling rate used in the cooling crystallization, which corresponds to the limitation of claims 6.
It would have been prima facie obvious for a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the cooling rate as taught by Giulietti to the particular cooling rate for obtaining high purity D-psicose crystals in view of Kim et al. because the cooling rate disclosed by Kim et al. is used for obtaining D-psicose crystals particularly. Thus, one of ordinary skill in the art would have had a reason to modify the cooling rate of Giulietti to the particular cooling rate in view of Kim et al. because it is the cooling rate specifically for obtaining D-psicose crystals. One would have been motivated to modify the cooling rate as taught by Giulietti to the particular cooling rate for obtaining high purity D-psicose crystals in view of Kim et al. because Kim et al. teach that the D-psicose crystals obtained have a purity of 98% (w/w) or more and a grain size of MA200 or more. One of ordinary skill in the art would have had a reasonable expectation of success to modify the cooling rate as taught by Giulietti to the particular cooling rate for obtaining high purity D-psicose crystals in view of Kim et al. because the cooling rate disclosed by Kim et al. is a known parameter for obtaining high purity D-psicose crystals.
Regarding the limitation “98% (w/w) or more D-psicose” of claim 1, it would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to modify the combined method of Lee et al. Muller, and Giulietti by employing the cooling crystallization conditions in view of Kim et al., which includes a cooling rate and crystallization duration effective to produce high-purity D-psicose crystals having a grain size of MA200 or greater. Kim et al. teach that such cooling conditions produce D-psicose crystals having a purity of at least 98% and a grain size of at least 200 μm. One of ordinary skill in the art would have been motivated to incorporated the disclosed crystallization parameters of Kim et al. into the known D-psicose crystallization process of Lee et al. because Kim et al. demonstrate that those parameters successfully produce highly pure D-psicose crystals of desirable size.
Regarding “0.001% (w/w) to 0.05% (w/w) ethanol” of claim 1, it would have been prima facie obvious for a person of ordinary skill to adjust the ethanol concentration remaining in the D-psicose crystals to a low residual amount, including within the claimed range of 0.001% to 0.05% (w/w) by drying because Lee et al teach drying the ed D-psicose crystals using a fluidized bed dry or vacuum drying and ICH teaches that ethanol is a Class 3 solvent for which low residual amounts are considered acceptable. One of ordinary skill in the art would have recognized that drying is a conventional technique for reducing residual solvent content in a crystalline product and would have been motivated to reduce residual ethanol in the final D-psicose crystal to a low level to improve product quality, reduce residual solvent, and provide a crystal suitable for food or pharmaceutical use. The claimed upper limit of 0.05% is below the ICH reporting threshold of 0.5% for Class 3 solvents and would have been an obvious range obtained by routine drying optimization. One of ordinary skill in the art would have had a reasonable expectation in reducing the ethanol concentration in the D-psicose crystal to 0.05% (w/w) or less because Lee et al. already teach drying the recovered crystals using drying equipment, such as fluidized bed dryer or vacuum dryer. Drying is a well-known process for removing volatile solvents, including ethanol, from crystalline products. Since ethanol is volatile and routinely removed by drying, one of ordinary skill in the art would have expected that the drying of Lee et al. would successfully reduce the residual ethanol content in the final crystal product to a low level that is within the limit disclosed by ICH, including 0.001% to 0.05% (w/w).
Regarding claim 7, Kim et al. teach that the D-psicose solution having a purity of 95% (w/w) in the crystallization device is cooled from 50 ⁰C to 35 ⁰C at a rate of 0.31 ⁰C per hour for 48 hours to perform crystallization. The disclosed crystallization time of 48 hours falls within the claimed range of 20 hours to 70 hours. Therefore, Kim et al. teach the limitation of claim 7.
Response to Applicant’s Remarks:
Applicant’s Remarks, filed May 11, 2026, have been fully considered and are found to be not persuasive.
Regarding the rejections of claims 3 – 5, 8 – 9, 13 – 17, and 21 – 23, Applicant argues that one of ordinary skill in the art would have no reason to combine the method of Lee et al. with Muller’s method due to the difference of crystallization behavior by the types of saccharides disclosed in the two references. Applicant points to Muller as teaching that (1) foreign components would influence the nucleation and growth of the crystal; (2) addition of anti-solvent would decrease the characteristics of the crystallizing system; and (3) anti-solvent would affect the taste, flavor, and smell of the final product.
Applicant further points to Giulietti as teaching that sugars in industrial formulations, such as sucrose, glucose, fructose, and lactose, have different characteristics that affect crystallization.
Applicant additionally cites Tas et al. as teaching that D-allulose exhibits the lowest interaction with water and submits that these results lead to reduced molecular mobility in aqueous solution, which can hinder nucleation and crystal growth.
The arguments are not persuasive because Applicant does not identify any disclosure in Muller, Giulietti, or Tas et al. demonstrating that anti-solvent crystallization using ethanol and water is inoperable, unsuitable, or incompatible with D-psicose. Instead, the cited portions merely recognize that crystallization behavior may vary among different saccharides and that process variables can influence nucleation, crystal growth, and product properties. Such teachings would have suggested routine optimization of crystallization parameters, not avoidance of anti-solvent crystallization.
Muller explicitly teaches anti-solvent crystallization as a generally applicable crystallization technique for highly soluble materials, wherein the addition of an anti-solvent reduces solubility and promotes crystal formation. Giulietti teaches anti-solvent crystallization of sugars using ethanol and water and demonstrates that crystallization conditions, such as solvent ratio, temperature, and cooling conditions may be adjusted to achieve desired crystallization results. These teachings would have suggested to one of ordinary skill in the art that anti-solvent crystallization principles are applicable across sugar systems, with operating parameters selected and optimized for the particular material being crystallized.
Applicant’s reliance on Tas et al. is also not persuasive. Even assuming D-psicose exhibits lower interaction with water than other sugars, Applicant has not provided evidence that such property would have discouraged the use of anti-solvent crystallization or rendered the claimed process unsuitable for D-psicose. Tas et al., at most, suggest that crystallization behavior may differ from that of other sugars, which would merely have required routine adjustment of known crystallization parameters. Differences in degree or optimization of known process conditions do not negate a motivation to combine.
Moreover, Lee et al. already teach crystallization of D-psicose from concentrated D-psicose solution under controlled supersaturation conditions. The proposed combination merely applies the known anti-solvent crystallization teachings of Muller and Giulietti to the known D-psicose crystallization process of Lee et al. in order to obtain the known benefits of anti-solvent crystallization, such as improved crystallization efficiency and crystal recovery. The combination, therefore, represents the predictable use of crystallization techniques from the prior art.
Regarding claims 1 – 2 and 6 – 7, Applicant argues that the Office “appear to have misunderstood the results of Table 2”. Applicant states that 18.3% of participants got the correct answer when Example 1 (i.e., 0.03% ethanol) and Examples 3 (i.e., 0.05% ethanol) were compared while it was 71.7% when Example 3 and Example 4 (i.e., 0.5% ethanol) were compared. Applicant argues that “the upper limit of the claimed range (i.e., 0.05% ethanol) is critical to achieve distinctive property of the claimed D-psicose”.
Applicant further argues that “a toxicologically acceptable amount of ethanol (i.e., less than 0.5%) does not lead to the conclusion that the ethanol content can be freely adjusted”. Applicant also argues that “the combination of the cited references fails to teach or suggest all the claimed limitations”, including “the specific amount of ethanol”, and therefore fails to satisfy the requirements of a prima facie case of obviousness.
Applicant’s argument regarding Table 2 is responsive to the Office’s prior discussion of Applicant’s asserted unexpected results in the Office Action mailed June 12, 2025. Applicant refers to Example 4 as containing 0.5% ethanol. However, the specification and Tables 1 – 3 identify Example 4 as containing 0.06% ethanol. The Office understand Applicant’s argument to refer to the 0.06% ethanol concentration disclosed for Example 4. However, the arguments are not persuasive. Although Table 2 suggests a sensory distinction between Example 3 containing 0.05% ethanol and Example 4 containing 0.06% ethanol, Applicant has not shown that the claimed range produces an expected result relative to the prior art. The asserted effect is reduced ethanol taste and smell when residual ethanol is reduced, which would have been expected. Further, the evidence is limited to sensory testing of selected examples and does not demonstrate that the claimed ethanol range, as a whole, produces a non-obvious or unexpected property. In addition, Table 2 does not show that samples within the claimed range are entirely indistinguishable. Even when Example 1 containing 0.03% ethanol and Example 3 containing 0.05% ethanol were compared, 18.3% of responses identified a difference. Thus, the data do not establish that 0.05% is a precise critical boundary. Rather, the data show varying degrees of sensory detectability as ethanol concentration changes. Accordingly, Applicant has not sufficiently demonstrated that the claimed upper limit of 0.05% ethanol is critical.
Regarding ICH, the Office does not rely on ICH as teaching the exact claimed ethanol range. ICH is cited to show that ethanol is a known residual solvent and that low residual levels of ethanol are recognized as acceptable in final products. Lee et al. teach drying recovered D-psicose crystals and drying is a conventional technique for reducing residual ethanol. Therefore, one of ordinary skill in the art would have been motivated to reduce residual ethanol through routine drying optimization to improve product quality and reduce residual solvent content.
Conclusion
No claim is found to be allowable.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HOI YAN LEE whose telephone number is 571-270-0265. The examiner can normally be reached Monday - Thursday 7:30 - 17:30.
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/H.Y.L./Examiner, Art Unit 1693
/SCARLETT Y GOON/Supervisory Patent Examiner, Art Unit 1693
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