1.Recent advances in the bio-production of human milk oligosaccharides 2'-FL and 3-FL.
Zheng XU ; Na LI ; Yingli CHEN ; Wenrui ZHANG ; Wanying ZHU
Chinese Journal of Biotechnology 2020;36(12):2767-2778
Human milk oligosaccharides (HMO) are important immunoactive components found in breast milk. Scientific research proves that HMOs are significantly beneficial for infant health. 2'-fucosyllactose (2'-FL) is the major component of HMO, which obtained growing attentions from food industry. Besides, 3-fucosyllactose (3-FL) is another important fucosyllactose and it has a similar synthetic route comparing to 2'-FL. Thus, research of the two HMO components has interactive effects for each other. Recently, numerous publications are available for 2'-FL and 3-FL. The microbial cell factory is able to massively produce fucosyllactose via an efficient way, which will show considerable influences in dairy industry. In this paper, we review recent studies on 2'-FL and 3-FL, and discuss their prospects according to published literature and patents.
Female
;
Humans
;
Infant
;
Milk, Human
;
Oligosaccharides
;
Trisaccharides
2.Blood glucose analysis in patients on continuous ambulatory peritoneal dialysis with Icodextrin.
Se Hee YOON ; Nak Won CHOI ; Sung Ro YUN
Korean Journal of Medicine 2008;74(2):170-175
BACKGROUND/AIMS: Icodextrin (glucose polymer) is metabolized by a-amylase to oligosaccharides such as maltose and maltotriose. The presence of these metabolites could have an effect on the enzymatic glucose measurement especially the glucose dehydrogenase pyrroloquinolinequinone (GDH-PQQ) based method. Patients treated with icodextrin are at risk for inaccurate blood glucose measurements. In this study we measured the blood glucose with different methods and analyzed the results to determine the test accuracy. METHODS: The blood glucose was measured, in seven outpatients and in seven inpatients using icodextrin, by the glucose hexokinase laboratory technique method as well as the GDH-PQQ method (Accu Chek Active)at the same time. To estimate an icodextrin residual effect, after discontinuing icodextin, the blood glucose was measured by the two methods after 48 hours in 4 inpatients. RESULTS: In seven outpatients the blood glucose was overestimated by the Accu Chek Active method (mean difference 68 mg/dL, p value 0.012). In seven inpatients the mean difference in the glucose was 56 mg/dL at 6am, 52 mg/dL at 11am, 52 mg/dL at 4pm, and 50 mg/dL at 9pm by the two different methods. In the four inpatients after changing their dialysate, the mean difference in the glucose was 58 mg/dL after 10 hours, 45 mg/dL after 24 hours, 24 mg/dL after 34 hours, and 26 mg/dL after 48 hours. CONCLUSION: Blood glucose was overestimated by the GDH-PQQ method and the inaccuracies were observed for more than 48 hours.
Blood Glucose
;
Glucans
;
Glucose
;
Glucose 1-Dehydrogenase
;
Hexokinase
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Humans
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Hypoglycemia
;
Inpatients
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Maltose
;
Oligosaccharides
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Outpatients
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Peritoneal Dialysis, Continuous Ambulatory
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Trisaccharides
3.Conformation and Linkage Studies of Specific Oligosaccharides Related to H1N1, H5N1, and Human Flu for Developing the Second Tamiflu.
Biomolecules & Therapeutics 2014;22(2):93-99
The interaction between viral HA (hemagglutinin) and oligosaccharide of the host plays an important role in the infection and transmission of avian and human flu viruses. Until now, this interaction has been classified by sialyl(alpha2-3) or sialyl(alpha2-6) linkage specificity of oligosaccharide moieties for avian or human virus, respectively. In the case of H5N1 and newly mutated flu viruses, classification based on the linkage type does not correlate with human infection and human-to-human transmission of these viruses. It is newly suggested that flu infection and transmission to humans require high affinity binding to the extended conformation with long length sialyl(alpha2-6)galactose containing oligosaccharides. On the other hand, the avian flu virus requires folded conformation with sialyl(alpha2-3) or short length sialyl(alpha2-6) containing trisaccharides. This suggests a potential future direction for the development of new species-specific antiviral drugs to prevent and treat pandemic flu.
Animals
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Antiviral Agents
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Classification
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Hand
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Humans
;
Influenza in Birds
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Influenza, Human*
;
Oligosaccharides*
;
Oseltamivir*
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Pandemics
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Sensitivity and Specificity
;
Trisaccharides
4.α-amylase detection methods and applications.
Chinese Journal of Biotechnology 2023;39(3):898-911
α-amylase is an endonucleoside hydrolase that hydrolyzes the α-1, 4-glycosidic bonds inside polysaccharides, such as starch, to generate oligosaccharides, dextrins, maltotriose, maltose and a small amount of glucose. Due to the importance of α-amylase in food industry, human health monitoring and pharmaceuticals, detection of its activity is widely required in the breeding of α-amylase producing strains, in vitro diagnosis, development of diabetes drugs, and the control of food quality. In recent years, many new α-amylase detection methods have been developed with improved speed and sensitivity. This review summarized recent processes in the development and applications of new α-amylase detection methods. The major principle of these detection methods were introduced, and their advantages and disadvantages were compared to facilitate future development and applications of α-amylase detection methods.
Humans
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alpha-Amylases/chemistry*
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Polysaccharides
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Oligosaccharides
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Starch
;
Maltose
5.Multicellular coupling fermentation for 3'-sialyllactose conversion using N-acetyl-glucosamine and lactose.
Wen ZHOU ; Xing YOU ; Hongtao ZHANG ; Zhongxia LI ; Chaoming DENG ; Chun XU ; Yu LI
Chinese Journal of Biotechnology 2023;39(11):4621-4634
Sialyllactose is one of the most abundant sialylated oligosaccharides in human milk oligosaccharides (HMOs), which plays an important role in the healthy development of infants and young children. However, its efficient and cheap production technology is still lacking presently. This study developed a two-step process employing multiple-strains for the production of sialyllactose. In the first step, two engineered strains, E. coli JM109(DE3)/ pET28a-BT0453 and JM109(DE3)/pET28a-nanA, were constructed to synthesize the intermediate N-acetylneuraminic acid. When the ratio of the biomass of the two engineered strains was 1:1 and the reaction time was 32 hours, the maximum yield of N-acetylneuraminic acid was 20.4 g/L. In the second step, E. coli JM109(DE3)/ pET28a-neuA, JM109(DE3)/ pET28a-nst and Baker's yeast were added to the above fermentation broth to synthesize 3'-sialyllactose (3'-SL). Using optimal conditions including 200 mmol/L N-acetyl-glucosamine and lactose, 150 g/L Baker's yeast, 20 mmol/L Mg2+, the maximum yield of 3'-SL in the fermentation broth reached 55.04 g/L after 24 hours of fermentation and the conversion rate of the substrate N-acetyl-glucosamine was 43.47%. This research provides an alternative technical route for economical production of 3'-SL.
Child
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Humans
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Child, Preschool
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N-Acetylneuraminic Acid
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Escherichia coli/genetics*
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Lactose
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Fermentation
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Saccharomyces cerevisiae
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Oligosaccharides
;
Glucosamine
6.Characterization of inulosucrase and the enzymatic synthesis of inulin.
Dawei NI ; Wei XU ; Ziwei CHEN ; Wenli ZHANG ; Wanmeng MU
Chinese Journal of Biotechnology 2021;37(1):266-275
As a type of prebiotics and dietary fiber, inulin performs plenty of significant physiological functions and is applied in food and pharmaceutical fields. Inulosucrase from microorganisms can use sucrose as the substrate to synthesize inulin possessing higher molecular weight than that from plants. In this work, a hypothetical gene coding inulosucrase was selected from the GenBank database. The catalytic domain was remained by N- and C- truncation strategies, constructing the recombinant plasmid. The recombinant plasmid was expressed in E. coli expression system, and after purifying the crude enzyme by Ni²⁺ affinity chromatography, a recombinant enzyme with a molecular weight of approximately 65 kDa was obtained. The optimal pH and temperature of the recombinant enzyme were 5.5 and 45 °C, respectively, when sucrose was used as the sole substrate. The activity of this enzyme was inhibited by various metal ions at different degrees. After purifying the produced polysaccharide, nuclear magnetic resonance analysis was used to determine that the polysaccharide was inulin connected by β-(2,1) linkages. Finally, the conditions for the production of inulin were optimized. The results showed that the inulin production reached the maximum, approximately 287 g/L after 7 h, when sucrose concentration and enzyme dosage were 700 g/L and 4 U/mL, respectively. The conversion rate from sucrose to inulin was approximately 41%.
Escherichia coli/genetics*
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Hexosyltransferases/genetics*
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Inulin
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Oligosaccharides
;
Sucrose
7.Diet and Nutritional Management in Functional Gastrointestinal Disorder: Irritable Bowel Syndrome.
Korean Journal of Medicine 2016;90(2):105-110
Irritable bowel syndrome (IBS) is a multifactorial disorder with the pathogenesis of abnormal gastrointestinal motility, low-grade inflammation, visceral hypersensitivity, communication in the gut-brain axis, and so on. Traditionally, IBS has been treated with dietary and lifestyle modification, fiber supplementation, pharmacological and psychological therapy. Carbohydrates have a range of foods regularly consumed including grains such as rye and wheat, vegetables, fruits, and legumes. Short-chain carbohydrates poorly absorbed exert osmotic effects in the intestinal lumen increasing its water volume, and are rapidly fermented by bacteria with consequent gas production. These effects may be the basis of the beginning of gastrointestinal symptoms. This made the use of lactose-free diets in those with lactose intolerance and of fructose-reduced diets for fructose malabsorption. All dietary poorly absorbed short-chain carbohydrates have similar and additive effects in the intestine, so a concept has been developed to regard them collectively as fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and to evaluate a dietary approach that restricts them all. Based on observational and comparative studies and on randomized-controlled trials, FODMAPs trigger gastrointestinal symptoms in patients with IBS. Food choice via the low FODMAP and potentially other dietary strategies is now a realistic and efficacious therapeutic approach for symptoms of IBS. In Korea, the strategy of Korean diet for Korean patients with IBS needs apposite to the Korean cases.
Axis, Cervical Vertebra
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Bacteria
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Carbohydrates
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Edible Grain
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Diet*
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Disaccharides
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Fabaceae
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Fructose
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Fruit
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Gastrointestinal Diseases*
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Gastrointestinal Motility
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Humans
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Hypersensitivity
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Inflammation
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Intestines
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Irritable Bowel Syndrome*
;
Korea
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Lactose Intolerance
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Life Style
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Monosaccharides
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Oligosaccharides
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Secale
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Triticum
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Vegetables
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Water
8.One step production of isomalto-oligosaccharides by engineered Yarrowia lipolytica yeast co-displayed β-amylase and α-transglucosidase.
Dawen LIU ; Hairong CHENG ; Zixin DENG
Chinese Journal of Biotechnology 2019;35(1):121-132
Isomalto-oligosaccharides (IMO) have good physiochemical properties and excellent physiological functions to make it widely used in food, medicine, feed, cosmetics and other industries. However, the procedures for industrial production of IMO are complicated. Therefore, it is necessary to develop an economical and easy-to-operate method. The genes encoding for β-amylase and α-transglucosidase were fused and co-displayed on the yeast cell surface of Yarrowia lipolytica which can convert liquefied starch to IMO in one step. The highest IMO purity of 75.3% was obtained using the displayed fusion-enzyme at 50 °C. This method showed potential application in IMO production.
Oligosaccharides
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Starch
;
Yarrowia
;
beta-Amylase
9.Equivalence Margin of the Biosimilar Product.
Journal of Korean Society for Clinical Pharmacology and Therapeutics 2012;20(1):17-33
The equivalence margin is the largest difference that is clinically acceptable between the test (or experimental) drug and the active control (or reference) drug. This paper discusses the scientific principles, along with the regulatory issues, that need to be addressed when determining the equivalence margin for the biosimilar product. The concept of assay sensitivity is introduced, and the ways to ensure assay sensitivity in the equivalence trial are emphasized. A hypothetical example is presented to show how an equivalence margin is determined. The regulatory agency should carefully assess if the equivalence margin of the biosimilar product was determined using a scientifically valid and clinically relevant approach, not subject to selection bias. This is important because the consumer risk of erroneously declaring equivalence when in fact it is not must be controlled conservatively low in the approval of any biosimilar products.
Dietary Sucrose
;
Selection Bias
10.Microplate Identification System of Enterobacteriaceae.
Young UH ; Jeong Seog SON ; Gyu Yel HWANG ; In Ho JANG ; Kap Jun YOON ; Dong Min SEO
Korean Journal of Clinical Microbiology 1999;2(2):135-143
BACKGROUND: To access the accuracy and clinical usefulness of microplate identification (ID) system for the identification of Enterobacteriaceae, we compared microplate ID system with API 20E(bioMerieux, Etoile, France). METHODS: Ninety-two cultures of Enterobacteriaceae and one isolate of Aeromonas species were simultaneously identified by microplate ID system and the API 20E. Twenty biochemical tests used in microplate ID system were lactose, sucrose, and H2S in Kligler's iron agar media; indole, sucrose, raffinose, arabinose, trehalose, adonitol, dulcitol, sorbitol, cellibiose, methy-red, phenylalanine deaminase, ornithine decarboxylase, lysine decarboxylase, arginine dihydrolase, urease, and citrate in microplate; and oxidase test. The identification was obtained by considering percent likelihood(% ID), modal frequency and ID score method. RESULTS: Among the 92 cultures of Enterobacteriaceae and one isolate of Aeromonas species, agreement rate of identification according to the % ID between microplate ID system and API 20E were 90.3% to the species level and 97.8% to the genus level. CONCLUSIONS: For the identification of clinical Enterobacteriaceae isolates, the microplate ID system compares favorably with API 20E in identification accuracy and have the advantage of costsaving and easy to use.
Aeromonas
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Agar
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Arabinose
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Arginine
;
Citric Acid
;
Enterobacteriaceae*
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Galactitol
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Iron
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Lactose
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Lysine
;
Ornithine Decarboxylase
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Oxidoreductases
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Phenylalanine
;
Raffinose
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Ribitol
;
Sorbitol
;
Sucrose
;
Trehalose
;
Urease