Safety evaluation of the food enzyme glutaminase from the genetically modified Bacillus licheniformis strain NZYM-JQ.

The food enzyme glutaminase (l-glutamine amidohydrolase EC 3.5.1.2) is produced with the genetically modified Bacillus licheniformis strain NZYM-JQ by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The production strain met the requirements for the qualified presumption of safety (QPS). The food enzyme is free from viable cells of the production organism and its DNA. The enzyme under assessment is intended to be used in six food manufacturing processes. Dietary exposure was estimated to be up to 0.148 mg TOS/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concern resulting from the food enzyme manufacturing process, toxicological studies were not considered necessary. A search was made for the similarity of the amino acid sequence to those of known allergens and one match with a pollen allergen was found. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, particularly for individuals sensitised to birch and oak pollen. The Panel concluded that the food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme glutaminase from the non-genetically modified Bacillus amyloliquefaciens strain AE-GT.

The food enzyme glutaminase (l-glutamine amidohydrolase; EC 3.5.1.2) is produced with the non-genetically modified Bacillus amyloliquefaciens strain AE-GT by Amano Enzyme Inc. The production strain met the requirements for the qualified presumption of safety (QPS) approach. The food enzyme is intended to be used in five food manufacturing processes. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.462 mg TOS/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme's manufacturing process, toxicity tests were considered unnecessary by the Panel. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that a risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Concurrent Ingestion of Alkaline Water and L-Glutamine Enhanced Salivary α-Amylase Activity and Testosterone Concentration in Boxing Athletes.

Athletes often take sport supplements to reduce fatigue and immune disturbances during or after training. This study evaluated the acute effects of concurrent ingestion of alkaline water and L-glutamine on the salivary immunity and hormone responses of boxers after training. Twelve male boxing athletes were recruited in this study. During regular training, the participants were randomly divided into three groups and asked to consume 400 mL of alkaline water (Group A), 0.15 g/kg body weight of L-glutamine with 400 mL of water (Group G), and 0.15 g/kg of L-glutamine with 400 mL of alkaline water (Group A+G) at the same time each day for three consecutive weeks. Before and immediately after the training, saliva, heart rates, and the rate of perceived exertion were investigated. The activity of α-amylase and concentrations of lactoferrin, immunoglobulin A (IgA), testosterone, and cortisol in saliva were measured. The results showed that the ratio of α-amylase activity/total protein (TP) significantly increased after training in Group A+G but not in Group A or G, whereas the ratios of lactoferrin/TP and IgA/TP were unaffected in all three groups. The concentrations of salivary testosterone after training increased significantly in Group A+G but not in Group A or G, whereas the salivary cortisol concentrations were unaltered in all groups. In conclusion, concurrent ingestion of 400 mL of alkaline water and 0.15 g/kg of L-glutamine before training enhanced the salivary α-amylase activity and testosterone concentration of boxers, which would be beneficial for post-exercise recovery.

Development of a Multifunctional Composite Hydrogel for Enhanced Wound Healing: Hemostasis, Sterilization, and Long-Term Moisturizing Properties.

Meeting the diverse requirements of effective wound repair while surpassing the single-function limitations of traditional wound dressings is a significant challenge. In this study, we successfully synthesized an inclusion complex of 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and iodine using the saturated aqueous solution method. Additionally, dialdehyde cellulose (DAC) was extracted from fat-free cotton through oxidation. To enhance wound healing, l-glutamine (l-glu) was utilized as a functional molecule, resulting in composite hydrogels with hemostatic, sterilizing, and wound-healing-promoting properties that were achieved by adsorbing the resulting inclusion complex. Through TG and SEM analysis, we confirmed that iodine was effectively accommodated by cyclodextrin and was uniformly attached to the hydrogel. The hydrogel exhibits exceptional long-term moisturizing and bactericidal properties, while also demonstrating excellent swelling, oxygen permeability, hemolytic, and mechanical properties, fully satisfying the requirements of wound treatment. External coagulation tests revealed that the hydrogel can rapidly coagulate 4.5 times its own weight of blood. Moreover, in a full-thickness scald mouse model, the hydrogel effectively promotes wound healing. The development of this multifunctional composite hydrogel presents a novel approach to advance wound dressing research, holding substantial potential for practical applications.

Identification of characteristic aroma compounds in chicken meat and their metabolic mechanisms using gas chromatography-olfactometry, odor activity values, and metabolomics.

Aroma has an important influence on the aroma quality of chicken meat. This study aimed to identify the characteristic aroma substances in chicken meat and elucidate their metabolic mechanisms. Using gas chromatography-olfactometry and odor activity values, we identified nonanal, octanal, and dimethyl tetrasulfide as the basic characteristic aroma compounds in chicken meat, present in several breeds. Hexanal, 1-octen-3-ol, (E)-2-nonenal, heptanal, and (E,E)-2,4-decadienal were breed-specific aroma compounds found in native Chinese chickens but not in the meat of white-feathered broilers. Metabolomics analysis showed that L-glutamine was an important metabolic marker of nonanal, hexanal, heptanal, octanal, and 1-octen-3-ol. Exogenous supplementation experiments found that L-glutamine increased the content of D-glucosamine-6-P and induced the degradation of L-proline, L-arginine, and L-lysine to enhance the Maillard reaction and promote the formation of nonanal, hexanal, heptanal, octanal, and 1-octen-3-ol, thus improving the aroma profile of chicken meat.

Real-world observational study on the long-term effect of L-glutamine treatment on renal parameters of adult and pediatric patients with sickle cell disease.

Background: Sickle cell disease (SCD) is a rare genetic blood condition affecting millions worldwide. Oxidative stress is a key player in the pathogenesis of SCD and its comorbid consequences. Renal function impairment is a common complication of SCD in both pediatric and adult patients with serious consequences leading to increased risk of mortality. In this observational real-world study, we are reporting the long-term (120 weeks) renal function in 10 patients treated with L-glutamine. Methods: Ten patients (4 pediatric and 6 adults), with confirmed diagnoses of SCD (HbSS genotype), were enrolled, these included four patients from Qatar with Arab Indian haplotype and six patients from French Guiana with African haplotype. All patients were treated with L-glutamine oral powder (~0.3 g/kg body weight, Endari®) twice daily for 120 weeks. Clinical events and laboratory parameters (renal function, hemoglobin, reticulocytes, and lactate dehydrogenase [LDH]) were measured at baseline, 48, and 120 weeks. Results: The study showed that with L-glutamine treatment there were improvements in renal and hematological parameters with no vaso-occlusive crisis at both 48-and 120-week follow-up time points in all 10 patients. Improvements were seen in the albumin creatinine ratio (ACR) from baseline to 48 weeks (mean [Standard deviation SD] ACR: -4.19 [9.81] mg/g) and 120 weeks (mean [SD] ACR: -12.31 [21.09] mg/g). Mean (SD) increase in hemoglobin concentrations from baseline to 48 weeks and 120 weeks was 0.72 (1) g/dL and 1.41 (0.79) g/dL, respectively. Mean (SD) reticulocyte counts and LDH levels decreased from baseline to 48 weeks (mean [SD] change from baseline to 48 weeks, reticulocyte counts: -40.30 [101.58] × 109 cells/L; LDH levels: -259 [154.93] U/L) and 120 weeks (mean [SD] change from baseline to 120 weeks, reticulocyte counts: -58.30 [128.38] × 109 cells/L; LDH levels: -344.80 [274.63] U/L). Conclusion: This is one of the first studies that assessed the long-term renal outcomes in SCD using L-glutamine. L-glutamine improved the renal function in patients with SCD along with improvements in clinical outcomes and hemolysis, from 48 weeks and sustained through 120 weeks of treatment.

The Effects of Ferulic Acid, Tryptophan, and L-Glutamine on the Cryopreservation of Mouse Spermatozoa.

In this study, the effects of ferulic acid (0.1, 1, ve 10 mM), tryptophan (5, 25, ve 50 mM), and L-glutamine (10, 50, ve 100 mM) at different doses added to 18% raffinose + 3% skimmed milk powder sperm extender on the freezing of mouse spermatozoa in liquid nitrogen were investigated. The combination of 18% raffinose + 3% skimmed milk powder without additives was used as the control group. Frozen spermatozoa were thawed in a 37°C water bath for 30 seconds. After freeze-thawing, motility, dead spermatozoa ratio, plasma membrane integrity, abnormal acrosome ratio, motility endurance (for 4 hours), and cell apoptosis tests were performed in Human Tubal Fluid (HTF). Compared with the control group after freezing and thawing, the highest motility and plasma membrane integrity were obtained in the 10 mM L-glutamine group with 56.6% ± 2.11% and 77.8% ± 0.87%, respectively (p < 0.05). In addition, when compared to the control group, the lowest rate of dead spermatozoa and abnormal acrosome was found in the 10 mM L-glutamine group as 26.0% ± 1.46% and 6.3% ± 1.09%, respectively (p < 0.05). The highest motility values for spermatozoa endurance were determined in the 10 and 50 mM L-glutamine groups up to the 4th hour compared to the control group (p < 0.05). In the evaluation of apoptosis in semen samples, there was no significant difference between the control, 0.1 mM ferulic acid, and 10 mM L-glutamine groups (p > 0.05). As a result, it was determined that the addition of 10 mM L-glutamine to the spermatozoa extender increased the motility, viable spermatozoa, functional membrane integrity, intact acrosome ratios, or motility endurance after freeze-thawing and could be used successfully in the freezing extender of mouse spermatozoa.

Stratification of ßSß+ Compound Heterozygotes Based on L-Glutamine Administration and RDW: Focusing on Disease Severity.

Sickle cell disease (SCD) is heterogeneous in terms of manifestation severity, even more so when in compound heterozygosity with beta-thalassemia. The aim of the present study was to stratify ßSß+ patient blood samples in a severity-dependent manner. Blood from thirty-two patients with HbS/ß-thalassemia compound heterozygosity was examined for several parameters (e.g., hemostasis, inflammation, redox equilibrium) against healthy controls. Additionally, SCD patients were a posteriori (a) categorized based on the L-glutamine dose and (b) clustered into high-/low-RDW subgroups. The patient cohort was characterized by anemia, inflammation, and elevated coagulation. Higher-dose administration of L-glutamine was associated with decreased markers of inflammation and oxidation (e.g., intracellular reactive oxygen species) and an altered coagulation profile. The higher-RDW group was characterized by increased hemolysis, elevated markers of inflammation and stress erythropoiesis, and oxidative phenomena (e.g., membrane-bound hemoglobin). Moreover, the levels of hemostasis parameters (e.g., D-Dimers) were greater compared to the lower-RDW subgroup. The administration of higher doses of L-glutamine along with hydroxyurea seems to attenuate several features in SCD patients, probably by enhancing antioxidant power. Moreover, anisocytosis may alter erythrocytes' coagulation processes and hemolytic propensity. This results in the disruption of the redox and pro-/anti-inflammatory equilibria, creating a positive feedback loop by inducing stress erythropoiesis and, thus, the occurrence of a mixed erythrocyte population.

L-glutamine protects against enterohemorrhagic Escherichia coli infection by inhibiting bacterial virulence and enhancing host defense concurrently.

IMPORTANCE: The type 3 secretion system (T3SS) was obtained in many Gram-negative bacterial pathogens, and it is crucial for their pathogenesis. Environmental signals were found to be involved in the expression regulation of T3SS, which was vital for successful bacterial infection in the host. Here, we discovered that L-glutamine (Gln), the most abundant amino acid in the human body, could repress enterohemorrhagic Escherichia coli (EHEC) T3SS expression via nitrogen metabolism and therefore had potential as an antivirulence agent. Our in vitro and in vivo evidence demonstrated that Gln could decline EHEC infection by attenuating bacterial virulence and enhancing host defense simultaneously. We repurpose Gln as a potential treatment for EHEC infection accordingly.

Sickle cell disease: combination new therapies vs. CRISPR-Cas9 potential and challenges - review article.

In 2022, sickle cell disease (SCD) continues to affect the lives of millions of people, being one of the most frequently inherited blood disorders worldwide. Recently, several new therapies have been FDA approved for the treatment of SCD. The complexity of the pathophysiology of sickling has given opportunity to the evolution of several modalities of therapies. Nonetheless, the potential for complementary targeting of HbS polymerization, vasocclusion, and other inflammatory pathways remains controversial. None of these drugs can be considered a single curative line of treatment. With the advancement of CRISPR/Cas9 technology, autologous transplant of gene-edited hematopoietic stem cells could possibly provide a cure for most patients with SCD. The advantage of this approach over the conventional stem cell transplantation is that it decreases the need for immuno-suppressive drugs and the risk of graft-versus-host disease. In addition, recent technological advances can reduce the off-target effects, but long-term monitoring is needed to ensure the reliability of these methods in the clinical setting. This review explores the efficacy and safety of combination therapies and contrasting this alternative with the challenges that exist with sickle cell gene therapy using CRISPR.

L-glutamine sensitizes Gram-positive-resistant bacteria to gentamicin killing.

IMPORTANCE: Methicillin-resistant Staphylococcus aureus (MRSA) infection severely threatens human health due to high morbidity and mortality; it is urgent to develop novel strategies to tackle this problem. Metabolites belong to antibiotic adjuvants which improve the effect of antibiotics. Despite reports of L-glutamine being applied in antibiotic adjuvant for Gram-negative bacteria, how L-glutamine affects antibiotics against Gram-positive-resistant bacteria is still unclear. In this study, L-glutamine increases the antibacterial effect of gentamicin on MRSA, and it links to membrane permeability and pH gradient (ΔpH), resulting in uptake of more gentamicin. Of great interest, reduced reactive oxygen species (ROS) by glutathione was found under L-glutamine treatment; USA300 becomes sensitive again to gentamicin. This study not only offers deep understanding on ΔpH and ROS on bacterial resistance but also provides potential treatment solutions for targeting MRSA infection.

C4BP(ß-)-mediated immunomodulation attenuates inflammation in DSS-induced murine colitis and in myeloid cells from IBD patients.

The most recent and promising therapeutic strategies for inflammatory bowel disease (IBD) have engaged biologics targeting single effector components involved in major steps of the immune-inflammatory processes, such as tumor necrosis factor, interleukins or integrins. Nevertheless, these molecules have not yet met expectations regarding efficacy and safety, resulting in a significant percentage of refractory or relapsing patients. Thus, novel treatment options are urgently needed. The minor isoform of the complement inhibitor C4b-binding protein, C4BP(ß-), has been shown to confer a robust anti-inflammatory and immunomodulatory phenotype over inflammatory myeloid cells. Here we show that C4BP(ß-)-mediated immunomodulation can significantly attenuate the histopathological traits and preserve the intestinal epithelial integrity in dextran sulfate sodium (DSS)-induced murine colitis. C4BP(ß-) downregulated inflammatory transcripts, notably those related to neutrophil activity, mitigated circulating inflammatory effector cytokines and chemokines such as CXCL13, key in generating ectopic lymphoid structures, and, overall, prevented inflammatory immune cell infiltration in the colon of colitic mice. PRP6-HO7, a recombinant curtailed analogue with only immunomodulatory activity, achieved a similar outcome as C4BP(ß-), indicating that the therapeutic effect is not due to the complement inhibitory activity. Furthermore, both C4BP(ß-) and PRP6-HO7 significantly reduced, with comparable efficacy, the intrinsic and TLR-induced inflammatory markers in myeloid cells from both ulcerative colitis and Crohn's disease patients, regardless of their medication. Thus, the pleiotropic anti-inflammatory and immunomodulatory activity of PRP6-HO7, able to "reprogram" myeloid cells from the complex inflammatory bowel environment and to restore immune homeostasis, might constitute a promising therapeutic option for IBD.

Synthesis of L-Ornithine- and L-Glutamine-Linked PLGAs as Biodegradable Polymers.

L-ornithine and L-glutamine are amino acids used for ammonia and nitrogen transport in the human body. Novel biodegradable synthetic poly(lactic-co-glycolic acid) derivatives were synthesized via conjugation with L-ornithine or L-glutamine, which were selected due to their biological importance. L-ornithine or L-glutamine was integrated into a PLGA polymer with EDC coupling reactions as a structure developer after the synthesis of PLGA via the polycondensation and ring-opening polymerization of lactide and glycolide. The chemical, thermal, and degradation property-structure relationships of PLGA, PLGA-L-ornithine, and PLGA-L-glutamine were identified. The conjugation between PLGA and the amino acid was confirmed through observation of an increase in the number of carbonyl carbons in the range of 170-160 ppm in the 13C NMR spectrum and the signal of the amide carbonyl vibration at about 1698 cm-1 in the FTIR spectrum. The developed PLGA-L-ornithine and PLGA-L-glutamine derivatives were thermally stable and energetic materials. In addition, PLGA-L-ornithine and PLGA-L-glutamine, with their unique hydrophilic properties, had faster degradation times than PLGA in terms of surface-type erosion, which covers their requirements. L-ornithine- and L-glutamine-linked PLGAs are potential candidates for development into biodegradable PLGA-derived biopolymers that can be used as raw materials for biomaterials.

L-Glutamine and Survival of Patients with Locally Advanced Head and Neck Cancer Receiving Chemoradiotherapy.

We previously reported that L-glutamine reduces the severity of mucositis caused by chemoradiotherapy in patients with head and neck cancer. However, the impact of glutamine on the anti-tumor effect of chemoradiotherapy remains controversial. This study, which included 40 patients, investigated whether L-glutamine influences survival. Radiation therapy (total: 66 or 70 Gy), cisplatin, and docetaxel were co-administered for a period of 6 weeks. Patients were randomly assigned to receive either glutamine (glutamine group, n = 20) or placebo (placebo group, n = 20) during the entire course of chemoradiotherapy. We compared the overall survival and progression-free survival rates between the two groups. At 5-year follow-up, 16 (80%) and 13 (72%) patients in the glutamine and placebo groups, respectively, survived (with no significant difference in overall survival [glutamine group: 55.2 ± 12.7 months vs. placebo group: 48.3 ± 21.3 months]). A total of 14 (70%) and 12 (67%) patients in the glutamine and placebo groups, respectively, did not experience disease progression (with no significant difference in progression-free survival [glutamine group: 46.7 ± 19.5 months vs. placebo group: 43.6 ± 25.2 months]). These findings indicate that L-glutamine does not influence the survival of patients with locally advanced head and neck cancer receiving chemoradiotherapy.

Advancements in Sickle Cell Disease (SCD) Treatment: A Review of Novel Pharmacotherapies and Their Impact on Patient Outcomes.

Sickle cell disease (SCD) is a genetic hereditary blood disease that disrupts normal beta-globin production. Patients with SCD experience a broad range of symptoms ranging from anemia, pain crises, and jaundice to acute coronary syndrome and stroke. SCD has been treated with hydroxyurea since 1998. Three important pharmacotherapies have been approved by the Food and Drug Administration (FDA) in the past few years. L-Glutamine has shown efficacy in reducing vaso-occlusive pain crises and hospitalization. Crizanlizumab has also shown positive outcomes in patients with SCD. Voxelotor has been studied to be effective in improving hemolytic anemia and the quality of life in SCD patients. These drugs can be used alone or in conjunction with hydroxyurea. Trials have shown that these therapies have significant efficacy. The events of pain, hemolytic anemia, vaso-occlusive crises, and hospitalizations have been reduced by using these agents. In this editorial, we will discuss these advanced treatment options for patients with SCD.

Long-Term L-Glutamine Treatment Reduces Hemolysis without Ameliorating Hepatic Vaso-Occlusion and Liver Fibrosis in a Mouse Model of Sickle Cell Disease.

Sickle cell disease (SCD) is an autosomal recessive monogenic disorder caused by a homozygous mutation in the ß-globin gene, which leads to erythrocyte sickling, hemolysis, vaso-occlusion, and sterile inflammation. The administration of oral L-glutamine has been shown to reduce the frequency of pain in SCD patients; however, the long-term effect of L-glutamine in SCD remains to be determined. To understand the long-term effect of L-glutamine administration in the liver we used quantitative liver intravital microscopy and biochemical analysis in humanized SCD mice. We here show that chronic L-glutamine administration reduces hepatic hemoglobin-heme-iron levels but fails to ameliorate ischemic liver injury. Remarkably, we found that this failure in the resolution of hepatobiliary injury and persistent liver fibrosis is associated with the reduced expression of hepatic Kupffer cells post-L-glutamine treatment. These findings establish the importance of investigating the long-term effects of L-glutamine therapy on liver pathophysiology in SCD patients.

Metabolic Heterogeneity, Plasticity, and Adaptation to "Glutamine Addiction" in Cancer Cells: The Role of Glutaminase and the GTωA [Glutamine Transaminase-ω-Amidase (Glutaminase II)] Pathway.

Many cancers utilize l-glutamine as a major energy source. Often cited in the literature as "l-glutamine addiction", this well-characterized pathway involves hydrolysis of l-glutamine by a glutaminase to l-glutamate, followed by oxidative deamination, or transamination, to α-ketoglutarate, which enters the tricarboxylic acid cycle. However, mammalian tissues/cancers possess a rarely mentioned, alternative pathway (the glutaminase II pathway): l-glutamine is transaminated to α-ketoglutaramate (KGM), followed by ω-amidase (ωA)-catalyzed hydrolysis of KGM to α-ketoglutarate. The name glutaminase II may be confused with the glutaminase 2 (GLS2) isozyme. Thus, we recently renamed the glutaminase II pathway the "glutamine transaminase-ω-amidase (GTωA)" pathway. Herein, we summarize the metabolic importance of the GTωA pathway, including its role in closing the methionine salvage pathway, and as a source of anaplerotic α-ketoglutarate. An advantage of the GTωA pathway is that there is no net change in redox status, permitting α-ketoglutarate production during hypoxia, diminishing cellular energy demands. We suggest that the ability to coordinate control of both pathways bestows a metabolic advantage to cancer cells. Finally, we discuss possible benefits of GTωA pathway inhibitors, not only as aids to studying the normal biological roles of the pathway but also as possible useful anticancer agents.

Substrate level optimization for better yield of oyster mushroom (Pleurotus ostreatus) production, using different ratio of rice straw and sugarcane bagasse.

Mushroom cultivation has been identified as a cost-effective technique for converting lignocellulosic wastes. This study utilized a combination of two distinct agro-wastes as a substrate for better Pleurotus ostreatus cultivation. Oyster mushroom has been cultivated on substrates made up of rice straw and sugarcane bagasse with different ratios. This technique gives a significant difference between mycelium running, fruit body formation, yield, biological efficiency, and better-quality taste of Pleurotus ostreatus mushroom. A minimum of 19 days were required for 1st harvesting from bag number T4 where substrate ratio was used at 3:2. The maximum yield was found as T4 (886 g/kg) in bag number on the dry substrate from the first flushing. According to proximate analyses, protein contents were increased in treatment bags compared with the control. Anyhow, the enrichment of L-glutamine content in the fruit body was found at 11.8 mg/g from 1st flushing in T4 bag, among the other bags and the flavour was changed due to the substrate level composition. According to the study, 3:2 is an ideal substrate ratio for the development of oyster mushrooms cultivation. According to this ratio, it helps the farmer for minimum time to grow the mushroom fruit body and reduce the lignocellulosic waste materials from the environmental pollution along with increasing the flavour in the fruitbody compared with commonly produced mushroom substrate (T6). Therefore, more research should be conducted to assess the consequences of combining different substrates and decreasing the lignocellulosic biomass by converting a protein-rich edible product through the oyster mushroom.

A L-glutamine binding protein modified MNM structured optical fiber biosensor based on surface plasmon resonance sensing for detection of L-glutamine metabolism in vitro embryo culture.

A surface plasmon resonance (SPR) optical fiber sensor with multimode-coreless-multimode (MNM) structure was developed, which modified by L-glutamine-binding protein (QBP) for detection of L-glutamine (Gln). The QBP was immobilized on the surface of gold films by chemical cross-linking and exhibited a binding affinity for L-glutamine. The conformation of QBP can be changed from the "open" to the "closed", which led to a red-shift of the SPR peak when QBP bounded to L-glutamine. There was a good linear correlation between is a dependence of the SPR peak on and the concentration of L-glutamine concentration in the range 10-100 µM, with a sensitivity of 10.797nm/log10[Gln] for L-glutamine in the in vitro embryo culture (IVC) medium environment, and the limit of detection (LOD) is 1.187 µM. This QBP-modified MNM structure optical fiber SPR sensor provides a new idea for the developmental potential assessment of embryos in the process of in vitro embryo culture.