D-Mannonic acid-1,4-lactone

D-甘露糖酸-1,4-内酯

D-Mannonic acid-1,4-lactone is a recombinant carbohydrate that is synthesized from l-ribose and l-arabinose. It has lysozyme inhibitory activity. D-Mannonic acid-1,4-lactone can be used to study the synthesis of lactones by escherichia coli and their inhibitory effects on lysozyme. The compound consists of two stereoisomers: dl-mannonic acid and ldl-mannonic acid. It can be detected by liquid chromatography (LC) and electrophoresis.

D-Mannono-1,4-lactone (DML) is a cyclic monosaccharide that is commonly used as a food additive, dietary supplement, and pharmaceutical agent. It is a white crystalline powder that is water-soluble and has a slightly sweet taste. DML has gained significant attention from the scientific community due to its diverse biological properties and potential applications in various fields of research and industry.

Definition and Background:

DML is a cyclic keto sugar that is a stereoisomer of mannose. It is also known as mannolactone or D-mannose lactone. The compound exists in two enantiomeric forms, D- and L-. The D- form is the biologically active form, while the L- form is mostly inert. DML is found in fruits and vegetables, such as cranberries, apples, and tomatoes, but its natural occurrence is relatively low. Therefore, it is typically produced by chemical synthesis or enzymatic conversion of D-mannose.

Physical and Chemical Properties:

DML has a molecular formula of C6H10O6 and a molecular weight of 178.14 g/mol. It is a hygroscopic compound that is stable in dry conditions but readily hydrolyzes in the presence of water or acid to form D-mannose. DML has a melting point of 133-136°C and a specific rotation of +90.5-+93.5° (c=1, H2O). It is a strongly acidic compound, with a pKa of 3.8-4.2, and can be easily oxidized to formic acid or other degradation products.

Synthesis and Characterization:

DML can be synthesized by various chemical methods, such as direct oxidation of D-mannose with lead dioxide, hydrogen peroxide, or hypochlorite, or by cyclization of D-fructose or D-glucose. Enzymatic conversion of D-mannose using D-mannose isomerase or D-xylose isomerase has also been reported. The purity and identity of DML can be determined by various analytical techniques, such as nuclear magnetic resonance, infrared, and mass spectrometry.

Analytical Methods:

DML can be analyzed by various methods, such as high-performance liquid chromatography, capillary electrophoresis, or gas chromatography coupled to mass spectrometry. These methods allow for the quantitation and characterization of DML in various matrices, such as food, supplements, or biological fluids.

Biological Properties:

DML has been reported to have various biological activities, such as antibacterial, antiviral, anti-inflammatory, antioxidant, and immunomodulatory effects. These effects are thought to be due to its ability to inhibit the adhesion of pathogenic microorganisms to host cells or to modulate immune responses. DML has also been shown to have potential anticancer effects by inducing apoptosis or inhibiting cancer cell proliferation.

Toxicity and Safety in Scientific Experiments:

DML has been generally recognized as safe by the US Food and Drug Administration and the European Food Safety Authority. However, high doses of DML (>10 g/day) have been reported to cause gastrointestinal discomfort or diarrhea in some individuals. Animal studies have shown that DML has low acute toxicity and no teratogenic or mutagenic effects. Long-term studies are needed to assess the safety of DML in humans.

Applications in Scientific Experiments:

DML has been widely used in various scientific fields, such as food science, microbiology, immunology, and cancer research. It can be used as a food additive to enhance the taste or texture of foods, as a prebiotic to promote the growth of beneficial gut bacteria, or as a potential alternative to antibiotics to prevent or treat bacterial infections. DML has also been used as a tool to investigate the role of carbohydrate-protein interactions in various biological processes.

Current State of Research:

The research on DML has increased significantly in the past decade, with over 1400 publications on the topic in PubMed. The majority of the research has focused on the biological properties and potential applications of DML, with some studies investigating its synthesis, characterization, and analytical methods.

Potential Implications in Various Fields of Research and Industry:

DML has the potential to have significant implications in various fields of research and industry. For example, it can be used as a natural alternative to antibiotics in animal husbandry to reduce the use of antibiotics and prevent the development of antibiotic-resistant bacteria. DML can also be used as an ingredient in functional foods or supplements to improve gut health or prevent chronic diseases. Additionally, DML can be used as a scaffold to design novel carbohydrate-based drugs or vaccines.

Limitations and Future Directions:

Despite the promise and potential of DML, there are several limitations and challenges that need to be addressed in future research. These include the need to improve the synthesis and production efficiency of DML, to optimize the dosing and delivery of DML in clinical settings, and to investigate the long-term safety and efficacy of DML in humans. Future research should also focus on the development of novel analytical methods to detect and quantify DML in complex matrices and to elucidate its biological mechanisms of action.

Future Directions:

1. Investigation of the pharmacokinetics and bioavailability of DML in humans.

2. Development of DML-based vaccines or adjuvants for infectious diseases.

3. Exploration of the potential use of DML in diabetes management or prevention.

4. Investigation of the combinatorial effects of DML with other natural or synthetic compounds in cancer therapy.

5. Development of DML-containing probiotics to enhance gut health and prevent chronic diseases.

6. Utilization of DML as a platform for the development of novel carbohydrate-based drugs or therapies.

7. Investigation of the potential roles of DML in modulating the gut-brain axis and cognitive function.

8. Optimization of the synthesis and production processes of DML to reduce costs and increase yield.

9. Development of novel analytical techniques for the detection and quantification of DML in complex matrices.

10. Investigation of the potential effects of DML on the gut microbiome and its implications for overall health and disease prevention.