L-arabinose isomerase (L-AI) is the key enzyme that isomerizes D-galactose to D-tagatose. In this study, to improve the activity of L-arabinose isomerase on D-galactose and its conversion rate in biotransformation, an L-arabinose isomerase from Lactobacillus fermentum CGMCC2921 was recombinantly expressed and applied in biotransformation. Moreover, its substrate binding pocket was rationally designed to improve the affinity and catalytic activity on D-galactose. We show that the conversion of D-galactose by variant F279I was increased 1.4 times that of the wild-type enzyme. The K_m and k_cat values of the double mutant M185A/F279I obtained by superimposed mutation were 530.8 mmol/L and 19.9 s^-1, respectively, and the catalytic efficiency was increased 8.2 times that of the wild type. When 400 g/L lactose was used as the substrate, the conversion rate of M185A/F279I reached a high level of 22.8%, which shows great application potential for the enzymatic production of tagatose from lactose.
Galactose/metabolism* ; Limosilactobacillus fermentum/genetics* ; Lactose ; Hexoses/metabolism* ; Aldose-Ketose Isomerases/genetics* ; Hydrogen-Ion Concentration

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 ; Humans ; Child, Preschool ; N-Acetylneuraminic Acid ; Escherichia coli/genetics* ; Lactose ; Fermentation ; Saccharomyces cerevisiae ; Oligosaccharides ; Glucosamine

OBJECTIVE: To study the efficacy and safety of lactase additive in improving lactose intolerance in preterm infants. METHODS: A total of 60 preterm infants with lactose intolerance who were admitted to the Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2018 to December 2019 were randomly divided into a lactase treatment group and a control group, with 30 infants in each group. The infants in the lactase treatment group were given 4 drops of lactase additive (180 mg) added into preterm formula or breast milk, and those in the control group were given placebo, oral administration of probiotics (live combined RESULTS: Finally 29 infants in the lactase treatment group and 26 infants in the control group completed the trial. At the end of the first week after intervention, compared with the control group, the lactase treatment group had significantly lower frequency of daily milk vomiting and gastric retention amount ( CONCLUSIONS Lactase additive can safely and effectively improve the clinical symptoms caused by lactose intolerance in preterm infants.
China ; Female ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; Lactase ; Lactose ; Lactose Intolerance/drug therapy* ; Prospective Studies

OBJECTIVES: To study the association between milk consumption and lactose malabsorption in Indonesian children aged 3-12 years. METHODS: This cross sectional study was conducted in randomly selected presumed healthy children with good nutritional status aged 3-12 years in Central Jakarta, Indonesia ( RESULTS: The prevalence of lactose malabsorption in children aged 3-5 years and children aged 6-12 years was 20.8% (15/72) and 35.3% (36/102), respectively. There was no association between milk or milk product consumption and lactose malabsorption ( CONCLUSIONS There is no association between milk consumption and lactose malabsorption in Indonesian children aged 3-12 years, suggesting that genetic predisposition may be more important than adaptive mechanisms to lactose consumption.
Animals ; Breath Tests ; Child ; Cross-Sectional Studies ; Humans ; Indonesia/epidemiology* ; Lactose Intolerance/epidemiology* ; Milk

Patients with a functional gastrointestinal disorder (FGID) frequently report abdominal discomfort and bloating after ingesting specific foods. However, evidence on the relationship between foods and symptoms is lacking. In addition, the diagnosis of food hypersensitivity and food intolerance does not seem to be established yet. Food hypersensitivity can be divided into immunologically mediated and non-immunologically mediated forms. The immunologically mediated forms are specifically termed food allergies, whereas the non-immunologically mediated forms are referred to as food intolerances. Various diagnostic tools are required to make an accurate diagnosis of a food allergy or a food intolerance. First, a thorough examination of the history and basic tests to rule out other organic diseases are needed. Next, diagnostic tests for immunoglobulin E-mediated food allergies are required and diseases, such as celiac disease and lactose intolerance, should be differentiated. A diagnosis for non-celiac gluten sensitivity (NCGS) is also required. A double blind, randomized, placebo-controlled, dietary challenge test can be used for diagnosing NCGS and food intolerance. Diagnostic tests for food intolerance, in which scientific evidence is lacking, may result in a misdiagnosis of food hypersensitivity or food intolerance in patients with a FGID. Therefore, an accurate diagnosis of food hypersensitivity or food intolerance based on reliable tests is required.
Celiac Disease ; Diagnosis ; Diagnostic Errors ; Diagnostic Tests, Routine ; Food Hypersensitivity ; Gastrointestinal Diseases ; Glutens ; Humans ; Immunoglobulins ; Lactose Intolerance

Human breast milk contains numerous biomolecules. Human milk oligosaccharides (HMOs) are the third most abundant component of breast milk, after lactose and lipids. Amongst the synthetized HMOs, 2′-fucosyllactose (2′-FL) and lacto-N-neotetraose (LNnT) are widely studied and are considered safe for infant nutrition. Several studies have reported the health benefits of HMOs, which include modulation of the intestinal microbiota, anti-adhesive effect against pathogens, modulation of the intestinal epithelial cell response, and development of the immune system. The amount and diversity of HMOs are determined by the genetic background of the mothers (HMO secretors or non-secretors). The non-secretor mothers secrete lower HMOs than secretor mothers. The breastfed infants of secretor mothers gain more health benefit than those of non-secretor mothers. In conclusion, supplementation of infant formula with 2′-FL and LNnT is a promising innovation for infant nutrition.
Breast Feeding ; Epithelial Cells ; Gastrointestinal Microbiome ; Genetic Background ; Health Maintenance Organizations ; Humans ; Immune System ; Infant Formula ; Infant ; Insurance Benefits ; Lactose ; Milk, Human ; Mothers ; Oligosaccharides

OBJECTIVES: This study examined the milk intake patterns with lactose and milk fat in Korean male adults using the following variables: milk intake level, awareness of lactose, and milk fat, health problems, and necessity of milk intake. In addition, the factors affecting milk intake were analyzed by multiple regression analysis. METHODS: The subjects were 532 males aged 20 years or older among the nationwide milk purchasing group. The subjects were 223 (41.9%) in the 20–29 year age group, 188 (35.3%) in the 30–49 year age group and 121(22.7%) in the over 50 year age group. The survey was conducted using ANOVA and multiple comparative analysis to examine the differences in age and multiple regression analysis was performed to investigate the factors affecting the intake of milk. RESULTS: The intake of milk in the subjects was 538.14 ± 494.23 ml per week. There were statistically significant differences in the subjects' age according to processed milk, low fat, nonfat milk, cheese, and ice cream. The perception of milk and lactose and milk fat was recognized as a good food for skeletal health when milk was consumed. Among the milk nutrients, lactose was highly recognized at the age of 20–29, and milk fat was recognized in those over 50 years. In addition to lactose and milk fat, calcium was the most highly recognized among the milk nutrients. Health problems associated with milk were skeletal health, obesity, and lactose intolerance. The perception of lactose intolerance was related to lactose intolerance and fatness, and the dietary behavior was unaffected. CONCLUSIONS: This study examined the milk intake patterns of adult Korean males. Many variables were found to be related to the intake of milk. In this study, the milk intake was high when there was no problem with the perception and dietary behaviors of milk nutrition (lactose and milk fat). This study focused on lactose and milk fat, which are major nutrients in milk, and it is a new perspective study among milk-related research.
Adult ; Calcium ; Cheese ; Humans ; Ice Cream ; Lactose Intolerance ; Lactose ; Male ; Milk ; Obesity

OBJECTIVES: This study examined the milk intake patterns with lactose and milk fat in Korean male adults using the following variables: milk intake level, awareness of lactose, and milk fat, health problems, and necessity of milk intake. In addition, the factors affecting milk intake were analyzed by multiple regression analysis. METHODS: The subjects were 532 males aged 20 years or older among the nationwide milk purchasing group. The subjects were 223 (41.9%) in the 20–29 year age group, 188 (35.3%) in the 30–49 year age group and 121(22.7%) in the over 50 year age group. The survey was conducted using ANOVA and multiple comparative analysis to examine the differences in age and multiple regression analysis was performed to investigate the factors affecting the intake of milk. RESULTS: The intake of milk in the subjects was 538.14 ± 494.23 ml per week. There were statistically significant differences in the subjects' age according to processed milk, low fat, nonfat milk, cheese, and ice cream. The perception of milk and lactose and milk fat was recognized as a good food for skeletal health when milk was consumed. Among the milk nutrients, lactose was highly recognized at the age of 20–29, and milk fat was recognized in those over 50 years. In addition to lactose and milk fat, calcium was the most highly recognized among the milk nutrients. Health problems associated with milk were skeletal health, obesity, and lactose intolerance. The perception of lactose intolerance was related to lactose intolerance and fatness, and the dietary behavior was unaffected. CONCLUSIONS: This study examined the milk intake patterns of adult Korean males. Many variables were found to be related to the intake of milk. In this study, the milk intake was high when there was no problem with the perception and dietary behaviors of milk nutrition (lactose and milk fat). This study focused on lactose and milk fat, which are major nutrients in milk, and it is a new perspective study among milk-related research.
Adult ; Calcium ; Cheese ; Humans ; Ice Cream ; Lactose Intolerance ; Lactose ; Male ; Milk ; Obesity

Infant formula is classified into standard cow's milk-based and special formulas. This review aimed at summarizing the types of special milk formulas currently sold in Korea, and the appropriate indications for the use of these formulas; lactose free formula, soy-based formula, protein hydrolysate formula, amino acid-based formula, preterm formula, medium chain triglyceride formula, low-phosphorus formula, protein-energy-enriched formula, and formulas for inborn errors of metabolism.
Humans ; Infant Formula* ; Infant* ; Korea* ; Lactose ; Metabolism, Inborn Errors ; Milk ; Protein Hydrolysates ; Soybeans ; Triglycerides

PURPOSE: Lactose intolerance (LI) is perceived to be frequent in Asia and has been reported to have considerable impact on dietary intake, nutritional status and the quality of life. We aimed to gather information from healthcare professionals on the perceived incidence, diagnosis and management of LI in 1 to 5 year old children in Southeast Asia. METHODS: An anonymous electronic survey was sent randomly among healthcare professionals registered in the database of the pediatric societies in Thailand, Indonesia, and Singapore between June and October 2016. RESULTS: In total, 259 health care professionals responded of which 45.5% (n=118) were from Thailand, 37.4% (n=97) from Indonesia and 16.9% (n=44) from Singapore. Of the participants who responded (n=248), primary LI prevalence among children 1 to 3 years of age was estimated to be less than 5% by 56.8%. However, about 18.9% (n=47) answered they did not know/unsure. Regarding secondary LI, 61.6% of respondents (n=153) estimated the prevalence to be less than 15%. But again, 10.8% (n=27) answered they did not know or unsure. Rotavirus gastroenteritis was ranked as the top cause for secondary LI. There was considerable heterogeneity in the diagnostic methods used. The majority of respondents (75%) recommended lactose-free milk to manage primary and secondary LI. CONCLUSION: More education/training of pediatricians on this topic and further epidemiological studies using a more systematic approach are required.
Anonyms and Pseudonyms ; Asia ; Asia, Southeastern ; Child* ; Delivery of Health Care ; Diagnosis ; Epidemiologic Studies ; Far East* ; Gastroenteritis ; Health Personnel ; Humans ; Incidence ; Indonesia ; Lactose Intolerance* ; Lactose* ; Milk ; Nutritional Status ; Population Characteristics ; Prevalence* ; Quality of Life ; Rotavirus ; Singapore ; Surveys and Questionnaires ; Thailand