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Song Y, Maskey S, Lee YG, Lee DS, Nguyen DT, Bae HJ. Optimizing bioconversion processes of rice husk into value-added products: D-psicose, bioethanol, and lactic acid. Bioresour Technol 2024; 395:130363. [PMID: 38253244 DOI: 10.1016/j.biortech.2024.130363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 01/24/2024]
Abstract
Rice husk, rich carbon content, is an agricultural waste produced globally at an amount of 120 million tons annually, and it has high potential as a biorefinery feedstock. Herein, we investigated the feasibility of producing various products as D-psicose, bioethanol and lactic acid from rice husk (RH) through a biorefinery process. Alkali-hydrogen peroxide-acetic acid pretreatment of RH effectively removed lignin and silica, resulting in enzymatic hydrolysis yield of approximately 86.3% under optimal hydrolysis conditions. By using xylose isomerase as well as D-psicose-3-epimerase with borate, glucose present in the RH hydrolysate was converted into D-psicose with a 40.6% conversion yield in the presence of borate. Furthermore, bioethanol (85.4%) and lactic acid (92.5%) were successfully produced from the RH hydrolysate. This study confirmed the high potential of RH as a biorefinery feedstock, and it is expected that various platform chemicals and value-added products can be produced using RH.
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Affiliation(s)
- Younho Song
- Bio-energy Research Center, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Shila Maskey
- Bio-energy Research Center, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Yoon Gyo Lee
- Bio-energy Research Center, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Dae-Seok Lee
- Bio-energy Research Center, Chonnam National University, Gwangju 61186, Republic of Korea
| | | | - Hyeun-Jong Bae
- Bio-energy Research Center, Chonnam National University, Gwangju 61186, Republic of Korea; Department of Bioenergy Science and Technology, Chonnam National University, Gwangju 61186, Republic of Korea.
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Duan S, Chen Y, Wang G, Li Z, Dong S, Wu Y, Wang Y, Ma C, Wang R. A study of targeted mutation of l-rhamnose isomerase to improve the conversion efficiency of D-allose. Enzyme Microb Technol 2023; 168:110259. [PMID: 37245327 DOI: 10.1016/j.enzmictec.2023.110259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 05/30/2023]
Abstract
D-Allose is a rare cis-caprose with a wide range of physiological functions, which has a wide range of applications in medicine, food, and other industries. L-Rhamnose isomerase (L-Rhi) is the earliest enzyme found to catalyze the production of D-allose from D-psicose. This catalyst has a high conversion rate, but its specificity for substrates is limited; thus, it cannot fulfill the requirements of industrial production of D-allose. In this study, L-Rhi derived from Bacillus subtilis was employed as the research subject, and D-psicose as the conversion substrate. Two mutant libraries were constructed through alanine scanning, saturation mutation, and rational design based on the analysis of the secondary structure, tertiary structure, and interactions with ligands of the enzyme. The yield of D-allose produced by these mutants was assessed; it was found that the conversion rate of mutant D325M to D-allose was increased by 55.73 %, and the D325S improved by 15.34 %, while mutant W184H increased by 10.37 % at 55 °C, respectively. According to modeling analysis, manganese (Mn2+) had no significant effect on the production of D-psicose from D-psicose by L-Rhi. The results of molecular dynamics simulation demonstrated that the mutants W184H, D325M, and D325S had more stable protein structures while binding with the substrate D-psicose, as evidenced by its root mean square deviation (RMSD), root mean square fluctuation (RMSF), and binding free energy values. It was more conducive to binding D-psicose and facilitating its conversion to D-allose, providing the basis for the production of D-allose.
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Affiliation(s)
- Shuangshuang Duan
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Yonghua Chen
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Guodong Wang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Zebin Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Shitong Dong
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Yingshuai Wu
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Yuanwei Wang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China
| | - Chunling Ma
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China.
| | - Ruiming Wang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, PR China; Shandong Provincial Key Laboratory of Microbial Engineering, Department of Bioengineering, Qilu University of Technology (Shandong Academy of Science) Jinan 250353, PR China.
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Li C, Gao L, Du K, Lin H, Ren Y, Lin J, Lin J. Production of D-allose from D-fructose using immobilized L-rhamnose isomerase and D-psicose 3-epimerase. Bioprocess Biosyst Eng 2020; 43:645-53. [PMID: 31797048 DOI: 10.1007/s00449-019-02262-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 11/24/2019] [Indexed: 01/28/2023]
Abstract
D-Allose is a rare sugar, can be used as an ingredient in a range of foods and dietary supplements, has alimentary activities, especially excellent anti-cancer effects and used in assisting cancer chemotherapy and radiotherapy, etc. To develop a simple and low-cost process for D-allose production, a one-pot enzymatic process using the substrate of D-fructose, and the recombinant enzymes of D-psicose 3-epimerase (DPE) and L-rhamnose isomerase (L-RhI) was developed. These enzymes were cloned from Ruminococcus sp. and B. subtilis, respectively, successfully expressed in E. coli, extracted and immobilized using anion exchange resin and amino resin, respectively. The mass ratio of D-fructose, D-psicose and D-allose was 6.6:2.4:1.0 when the reaction reached equilibrium after 5 h of reaction. Using the low-cost substrate of D-fructose, the reusable immobilized enzymes and the one-pot reaction, the production process is simplified and the production cost is decreased. In addition, to simplify the enzyme extraction and immobilization processes, new methods for enzyme capture and immobilization were developed especially for DPE immobilization. This is the first report for one-pot D-allose production using immobilized L-RhI and DPE.
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An M, Lee J, Park YC, Park C, Kim HJ. 90-Day repeated oral toxicity test of D-allulose produced from Microbacterium foliorum. Regul Toxicol Pharmacol 2019; 109:104485. [PMID: 31568817 DOI: 10.1016/j.yrtph.2019.104485] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 09/24/2019] [Accepted: 09/25/2019] [Indexed: 10/25/2022]
Abstract
D-allulose is considered an ideal substitute for sucrose, because it has 70% of the sweetness of sucrose and ultra-low energy. Chemical and biotechnological methods have been developed to produce Dallulose from D-fructose because D-allulose exists in extremely small quantities in nature. In this study, we performed a 90-day repeated oral dose toxicity test on rats using D-allulose produced from Microbacterium foliorum-a non-GMO species isolated from salad ginseng-in dosages of 0, 1250, 2500 and 5000 mg/kg/day. We developed a toxicity determination criterion based on the significant change caused by the administration of the substance to estimate the NOEL, NOAEL, and LOAEL of the substance applied in this study. This test found only minor compound-related changes in both male and female rats in the high dose group and no important compound-related changes. Thus, we determined the NOAEL of Dallulose in both sexes to be 5,000 mg/kg/day. This study's finding of a NOAEL of 5,000 mg/kg/day should ensure that D-allulose produced from Microbacterium foliorum is classified as a safe and ordinary substance.
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Affiliation(s)
- MinJi An
- GLP Center & Dept. of Toxicity Assessment, Daegu Catholic University, Gyeongsan, 38430, Republic of Korea
| | - JiSun Lee
- GLP Center & Dept. of Toxicity Assessment, Daegu Catholic University, Gyeongsan, 38430, Republic of Korea
| | - Yeong-Chul Park
- GLP Center & Dept. of Toxicity Assessment, Daegu Catholic University, Gyeongsan, 38430, Republic of Korea
| | - ChongJin Park
- Samyang Corp, 295 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea
| | - Hye-Jung Kim
- Samyang Corp, 295 Pangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea.
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Abstract
Cell-free systems are promising platforms for rapid and high-throughput prototyping of biological parts in metabolic engineering and synthetic biology. One main limitation of cell-free system applications is the low fold repression of transcriptional repressors. Hence, prokaryotic biosensor development, which mostly relies on repressors, is limited. In this study, we demonstrate how to improve these biosensors in cell-free systems by applying a transcription factor (TF)-doped extract, a preincubation strategy with the TF plasmid, or reinitiation of the cell-free reaction (two-step cell-free reaction). We use the optimized biosensor to sense the enzymatic production of a rare sugar, D-psicose. This work provides a methodology to optimize repressor-based systems in cell-free to further increase the potential of cell-free systems for bioproduction.
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Affiliation(s)
- Amir Pandi
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas 78352, France
| | - Ioana Grigoras
- iSSB Laboratory, Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Université Evry, Université Paris-Saclay, 91057 Evry, France
| | - Olivier Borkowski
- iSSB Laboratory, Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Université Evry, Université Paris-Saclay, 91057 Evry, France
| | - Jean-Loup Faulon
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas 78352, France
- iSSB Laboratory, Génomique Métabolique, Genoscope, Institut François Jacob, CEA, CNRS, Université Evry, Université Paris-Saclay, 91057 Evry, France
- SYNBIOCHEM Center, School of Chemistry, University of Manchester, Manchester M13 9PL, U.K
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Shen X, Wang J, Zhang Y, Wang X, Ding Z, Li Y, Chen B, Tong Y. [Research progress of D-psicose: function and its biosynthesis]. Sheng Wu Gong Cheng Xue Bao 2019; 34:1419-1431. [PMID: 30255676 DOI: 10.13345/j.cjb.170526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
As the morbidity of metabolic syndrome like obesity and diabetes increases rapidly worldwide, the issue of nutrition (functional food) and health has drawn more attention. D-psicose, a rare natural ketohexose, has become a hot topic in functional food and health-care field because of its hypoglycemic and hypolipidemic function with good sweetness. This article mainly discusses the functional properties and biosynthesis research progress of D-psicose, together with the crystal structure of ketose-3-epimerase, to provide theoretical guidance for D-psicose-producing strain screening as well as improving the thermostability and catalytic efficiency of ketose-3-epimerase for industrial application.
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Affiliation(s)
- Xuemei Shen
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Jing Wang
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Yuan Zhang
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Xiaoyan Wang
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Ziyuan Ding
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Yi Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Bo Chen
- Nutrition & Health Research Institute, China National Cereals, Oils and Foodstuffs Corporation (COFCO), Beijing 102209, China.,Beijing Key Laboratory of Nutrition, Health and Food Safety, Beijing 102209, China.,Beijing Engineering Laboratory for Geriatric Nutrition Food Research, Beijing 102209, China
| | - Yi Tong
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
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Juneja A, Zhang G, Jin YS, Singh V. Bioprocessing and technoeconomic feasibility analysis of simultaneous production of d-psicose and ethanol using engineered yeast strain KAM-2GD. Bioresour Technol 2019; 275:27-34. [PMID: 30576911 DOI: 10.1016/j.biortech.2018.12.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
The objective of this study was to analyze the processing and technoeconomic feasibility of coproduction of d-psicose and ethanol in a modified dry grind ethanol process. The yeast strain was constructed by expressing d-psicose 3-epimerases (DPE) in Sachharomyces cerevisiae. The strain was capable of converting d-fructose to d-psicose at 55 °C with a conversion efficiency of 26.6%. A comprehensive process model for modified dry grind ethanol plant with 396,000 MT/yr corn processing capacity was developed using SuperPro Designer. Predicted ethanol and d-psicose yields were 390.4 L and 75.3 kg per MT of corn, with total annual production of 154.6 million L and 29,835 MT respectively. The capital investment for the plant was estimated as 150.3 million USD with total operating cost of 85.2 million USD/yr. The unit production cost and minimum selling price of d-psicose with an internal rate of return of 15% were calculated as $0.43/kg and $1.29/kg respectively.
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Affiliation(s)
- Ankita Juneja
- Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Guochang Zhang
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States; Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States; Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Vijay Singh
- Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
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Braunstein CR, Noronha JC, Glenn AJ, Viguiliouk E, Noseworthy R, Khan TA, Au-Yeung F, Blanco Mejia S, Wolever TMS, Josse RG, Kendall CWC, Sievenpiper JL. A Double-Blind, Randomized Controlled, Acute Feeding Equivalence Trial of Small, Catalytic Doses of Fructose and Allulose on Postprandial Blood Glucose Metabolism in Healthy Participants: The Fructose and Allulose Catalytic Effects (FACE) Trial. Nutrients 2018; 10:E750. [PMID: 29890724 DOI: 10.3390/nu10060750] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/01/2018] [Accepted: 06/07/2018] [Indexed: 01/24/2023] Open
Abstract
Recent literature suggests that catalytic doses (≤10 g/meal or 36 g/day) of D-fructose and D-allulose may reduce postprandial blood glucose responses to carbohydrate loads in people with and without type 2 diabetes by inducing glycogen synthesis. To assess the effect of small single doses of fructose and allulose on postprandial blood glucose regulation in response to a 75 g-oral glucose tolerance test (75 g-OGTT) in healthy individuals, we conducted an acute randomized, crossover, equivalence trial in healthy adults. Each participant randomly received six treatments, separated by a minimum one-week washout. Treatments consisted of a 75 g-OGTT with the addition of fructose or allulose at 0 g (control), 5 g or 10 g. A standard 75 g-OGTT protocol was followed with blood samples at −30, 0, 30, 60, 90, 120 min. The primary outcome was the difference in plasma glucose incremental area under the curve (iAUC). A total of 27 participants underwent randomization with data available from 25 participants. Small doses of fructose or allulose did not show a significant effect on plasma glucose iAUC or other secondary markers of postprandial blood glucose regulation in response to a 75 g-OGTT in healthy individuals. These results were limited by the low power to detect a significant difference, owing to greater than expected intra-individual coefficient of variation (CV) in plasma glucose iAUC. Overall, we failed to confirm the catalytic effects of small doses of fructose and allulose in healthy individuals. Future trials may consider recruiting larger sample sizes of healthy individuals. Trial registration: clinicaltrials.gov identifier, NCT02459834.
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Han W, Zhu Y, Men Y, Yang J, Liu C, Sun Y. Production of allitol from D-psicose by a novel isolated strain of Klebsiella oxytoca G4A4. J Basic Microbiol 2014; 54:1073-9. [PMID: 24771547 DOI: 10.1002/jobm.201300647] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 12/06/2013] [Indexed: 11/07/2022]
Abstract
A novel bacterium capable of producing allitol from D-psicose was isolated from soil and identified as Klebsiella oxytoca G4A4. An efficient method for the transformation of D-psicose to allitol was achieved through the resting cell reaction. Ribitol as an inducer is suitable for cell cultivation, and cells are most active in Tris-HCl buffer (pH 8.0) at 37 °C with a density of 40 (OD600 nm ). After the reaction, the final conversion rates of the washed cells were approximately 87, 83, and 55% at D-psicose concentrations of 0.25, 0.5, and 1%, respectively. The product from D-psicose was purified and determined to be allitol by high-performance liquid chromatography and nuclear magnetic resonance spectroscopy.
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Affiliation(s)
- Wenjia Han
- National Engineering Laboratory for Industrial Enzymes, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, P. R., China
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Abstract
Now a days sugar free food are very much popular because of their less calorie content. So food industry uses various artificial sweeteners which are low in calorie content instead of high calorie sugar. U.S. Food and Drug Administration has approved aspartame, acesulfame-k, neotame, cyclamate and alitame for use as per acceptable daily intake (ADI) value. But till date, breakdown products of these sweeteners have controversial health and metabolic effects. On the other hand, rare sugars are monosaccharides and have no known health effects because it does not metabolize in our body, but shows same sweet taste and bulk property as sugar. Rare sugars have no such ADI value and are mainly produced by using bioreactor and so inspite of high demand, rare sugars cannot be produced in the desired quantities.
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Affiliation(s)
- Sanchari Chattopadhyay
- Department of Food Technology and Biochemical Engineering, Jadavpur University, Kolkata, 700032 India
| | - Utpal Raychaudhuri
- Department of Food Technology and Biochemical Engineering, Jadavpur University, Kolkata, 700032 India
| | - Runu Chakraborty
- Department of Food Technology and Biochemical Engineering, Jadavpur University, Kolkata, 700032 India
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Abstract
D-Psicose is a rare sugar present in small quantities in natural products. In a previous study, we showed that D-psicose suppresses plasma glucose increases and reduces body fat accumulation in rats. Based on acute toxicity testing in rats, D-psicose is classified as an ordinary substance (LD(50) = 16 g/kg). Elucidating the effects of long term feeding of D-psicose in rats will be essential prior to its utilization as a physiologically functional food. In this study, male Wistar rats (3 weeks old) were fed diets containing 3% D-psicose or sucrose for 12-18 months. The rats actually ingested 1.28 g/kg body weight per day D-psicose or 1.22 g/kg body weight per day of sucrose. Body weight gain and intra-abdominal adipose tissue weight in rats fed the D-psicose diet for 18 months were significantly lower than those in rats fed the sucrose diet. Relative weights of liver and kidney were significantly higher in the D-psicose group than in the sucrose group. However, no gross pathological findings were evident at dietary doses of 3% D-psicose or correlated with hypertrophy of liver and kidney. No clinical chemical test value was suggestive of overt D-psicose treatment-related toxicity. Therefore, the present study found no adverse effects at 3% D-psicose in the diet.
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Affiliation(s)
- Kanako Yagi
- Faculty of Agriculture, Kagawa University, Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0795, Japan
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