Monolaurin Research Articles

In vivo antiviral effect of plant essential oils against avian infectious bronchitis virus

BackgroundInfectious bronchitis virus (IBV) leads to huge economic losses in the poultry industry worldwide. The high levels of mutations of IBV render vaccines partially protective. Therefore, it is urgent to explore an effective antiviral drug or agent. The present study aimed to investigate the in vivo anti-IBV activity of a mixture of plant essential oils (PEO) of cinnamaldehyde (CA) and glycerol monolaurate (GML), designated as Jin-Jing-Zi.ResultsThe antiviral effects were evaluated by clinical signs, viral loads, immune organ indices, antibody levels, and cytokine levels. The infection rates in the PEO-M (middle dose) and PEO-H (high dose) groups were significantly lower than those in the prevention, positive drug, and PEO-L (low dose) groups. The cure rates in the PEO-M and PEO-H groups were significantly higher than those in the prevention, positive drug, and PEO-L groups, and the PEO-M group had the highest cure rate of 92.31%. The symptom scores and IBV mRNA expression levels were significantly reduced in the PEO-M group. PEO significantly improved the immune organ indices and IBV-specific antibody titers of infected chickens. The anti-inflammatory factor levels of IL-4 and IFN-γ in the PEO-M group maintained high concentrations for a long time. The IL-6 levels in the PEO-M group were lower than those in prevention, positive drug, and PEO-L groups.ConclusionThe PEO had remarkable inhibition against IBV and the PEO acts by inhibiting virus multiplication and promoting immune function, suggesting that the PEO has great potential as a novel anti-IBV agent for inhibiting IBV infection.

Fabrication of chitosan-cinnamaldehyde-glycerol monolaurate bigels with dual gelling effects and application as cream analogs

In this study, chitosan-based bigels were fabricated, where glycerol monolaurate was added in MCT oil to produce a gelled lipid phase and cinnamaldehyde was included in the lipid phase in order to act as a crosslinking agent. The synergistic effect of pH on chemical crosslinking effects was investigated. The potential of using these bigels as an alternative to cream was also investigated. The pH of the aqueous phase played an important role in controlling the extent of the Schiff-base reaction promoted by cinnamaldehyde. At pH 3.8, the bigels formed were homogenous but at pH 5.0 and 5.5 they exhibited phase separation, which highlighted the importance of chemical crosslinking. To better mimic the properties of real cream, span 80 was added to create a more homogeneous and smoother structure of the bigels. These bigels might provide a healthy and more sustainable alterative to food products that contain plastic fats, like cream.

The formation of starch-lipid complexes by microwave heating

This study investigated the impact of microwave treatment on the formation of starch-lipid complexes, and physicochemical properties of wheat starch (WS) fortified with lipids, such as lauric acid (LA), glycerol monolaurate (GML), and stearic acid (SA). Specimens were prepared using a conventional water bath and microwave heating and evaluated using macrostructural and microstructural analyses. Iodine staining and scanning electron microscopy revealed interplay between WS and LA. Diffraction peaks around 7.5°, 13°, and 20° and the absence of the absorption band in the 2850 cm−1 were observed in microwave treated WS-lipid samples than conventional water bath samples. Further, more type I complexes were formed in WS-LA microwave-assisted samples, as demonstrated by differential scanning calorimetry. Additionally, more resistant starch was formed in specimens treated by microwave than water bath treated counterparts, the finding that was proved by in vitro enzymatic hydrolysis. In short, the current study may suggest the applications of microwave treatment in foods for hypoglycemia.

Monolaurin Confers a Protective Effect Against Porcine Epidemic Diarrhea Virus Infection in Piglets by Regulating the Interferon Pathway.

Porcine epidemic diarrhea virus (PEDV) has reemerged as the main pathogen of piglets due to its high mutation feature. Monolaurin (ML) is a natural compound with a wide range of antibacterial and antiviral activities. However, the role of ML in PEDV infection is still unknown. This study aimed to evaluate the effect of ML on the growth performance, intestinal function, virus replication and cytokine response in piglets infected with PEDV, and to reveal the mechanism through proteomics analysis. Piglets were orally administrated with ML at a dose of 100 mg/kg·BW for 7 days before PEDV infection. Results showed that although there was no significant effect on the growth performance of piglets, ML administration alleviated the diarrhea caused by PEDV infection. ML administration promoted the recovery of intestinal villi, thereby improving intestinal function. Meanwhile, PEDV replication was significantly inhibited, and PEDV-induced expression of IL-6 and IL-8 were decreased with ML administration. Proteomics analyses showed that 38 proteins were differentially expressed between PEDV and ML+PEDV groups and were significantly enriched in the interferon-related pathways. This suggests ML could promote the restoration of homeostasis by regulating the interferon pathway. Overall, the present study demonstrated ML could confer a protective effect against PEDV infection in piglets and may be developed as a drug or feed additive to prevent and control PEDV disease.

Preparation of porous polyaminobenzenesulfonic acid and synthesis of glycerol monolaurate

Preparation of porous polyaminobenzenesulfonic acid and synthesis of glycerol monolaurate

Dietary Glycerol Monolaurate Improves Bone Growth Through the Regulation of Igf-1 in Fish Model

Dietary Glycerol Monolaurate Improves Bone Growth Through the Regulation of Igf-1 in Fish Model

Covalent Immobilization of Heteropoly Acid in Magnetic Yolk-Shell Nanostructured Materials and its Catalytic Properties for the Preparation of Glycerol Monolaurate

Covalent Immobilization of Heteropoly Acid in Magnetic Yolk-Shell Nanostructured Materials and its Catalytic Properties for the Preparation of Glycerol Monolaurate

Study on the digestive characteristics of short-and medium-chain fatty acid structural lipid and its rapid intervention on gut microbes: In vivo and in vitro studies

Structuring is a feasible scheme to improve lipids’ value. Here, SBL and SLBL (C4-C12 structural lipids) were obtained through enzymatic ester-ester transesterification or acidolysis interesterification using glyceryl tributyrate/glyceryl tridodecanoate and lauric acid/glyceryl tributyrate as raw materials, respectively. The digestive characteristics of SBL and SLBL were investigated in vitro and in vivo, meanwhile, their effects on gut microbes were studied. Compared with their corresponding triglyceride physical mixture, SBL possessed an ideal butyric acid sustained-release effect in simulated stomach digestion. Moreover, the sustained-release effect of SLBL on glycerol monolaurate (GML) was revealed both in vivo and in vitro, while this effect of the SBL was obviously occurred in small intestine. SBL significantly increased the abundance of Bifidobacterium and SLBL promoted the growth of Clostridiales within 24 h. Overall, both SBL and SLBL showed ideal sustained-release effects on GML rather than butyric acid, which may lead to positive changes in gut microbes.

Novel Gut Microbiota Patterns Involved in the Attenuation of Dextran Sodium Sulfate-Induced Mouse Colitis Mediated by Glycerol Monolaurate via Inducing Anti-inflammatory Responses.

ABSTRACTInflammatory bowel disease (IBD) is a type of immune-mediated chronic and relapsing inflammatory gastrointestinal symptoms. IBD cannot be completely cured because of the complex pathogenesis. Glycerol monolaurate (GML), naturally found in breast milk and coconut oil, has excellent antimicrobial, anti-inflammatory, and immunoregulatory functions. Here, the protective effect of GML on dextran sodium sulfate (DSS)-induced mouse colitis and the underlying gut microbiota-dependent mechanism were assessed in C57BL/6 mice pretreated or cotreated with GML and in antibiotic-treated mice transplanted with GML-modulated microbiota. Results showed that GML pretreatment has an advantage over GML cotreatment in alleviating weight loss and reducing disease activity index (DAI), colonic histological scores, and proinflammatory responses. Moreover, the amounts of Lactobacillus and Bifidobacterium and fecal propionic acid and butyric acid were elevated only in mice pretreated with GML upon DSS induction. Of note, fecal microbiota transplantation (FMT) from GML-pretreated mice achieved faster and more significant remission of DSS-induced colitis, manifested as reduced DAI, longer colon, decreased histological scores, and enhanced colonic Foxp3+ regulatory T cells (Tregs) and ratio of serum anti-inflammatory/proinflammatory cytokines, as well as the reconstruction of microbial communities, including elevated Helicobacter ganmani and decreased pathogenic microbes. In conclusion, GML-mediated enhancement of Bifidobacterium and fecal short-chain fatty acids (SCFAs) could be responsible for the anticolitis effect. FMT assay confirmed that gut microbiota modulated by GML was more resistant to DSS-induced colitis via elevating beneficial H. ganmani and establishing Treg tolerant phenotype. Importantly, colitis remission induced by GML is associated with novel gut microbiota patterns, even though different microbial contexts were involved.

Effect of supplemental glycerol monolaurate and oregano essential oil blend on the growth performance, intestinal morphology, and amino acid digestibility of broiler chickens

BackgroundThis experiment tested the impact of the combined supplementation of glycerol monolaurate (GLM) and oregano essential oil (EO) to broiler diets. Growth performance, metabolic response, immune status, apparent ileal digestibility coefficient (AID%), and intestinal histomorphology were assessed. Three-day-old Ross-308 broilers (76.62 g ± 0.50, n = 240) were randomly allocated into 4 experimental groups (6 replicates/group and 10 chicks/replicate). Birds were fed corn-soybean meal basal diets supplemented with four levels of GLM and oregano EO blend: 0, 0.15, 0.45, and 0.75% for 35 days.ResultsDuring the starter period, dietary GLM and oregano EO did not show significant (P > 0.05) changes in growth performance. During the grower period, GLM and oregano EO supplemented groups showed a linear and quadratic decline in FCR. During the finisher and overall performance, a linear increase in the body weight (BW), body weight gain (BWG), the protein efficiency ratio (PER), and relative growth rate (RGR), and a linear decrease in the FCR at 0.75% dietary level of GLM and oregano EO compared to the control. The broken-line regression model showed that the optimum dietary level of GLM and oregano EO blend was 0.58% based on final BW and FCR. The 0.45% or 0.15% dietary level of supplemented additives lowered (P < 0.05) the AID% of threonine and arginine, respectively, with no change in the AID% of other assessed amino acids at all dietary levels. Muscle thickness in jejunum and ileum in all dietary supplemented groups was increased (P < 0.05); however, such increase (P < 0.05) in the duodenum was shown at 0.45 and 0.75% dietary levels. All GLM and oregano EO supplemented groups showed increased (P < 0.05) duodenal, jejunal, and ileal villus height. The 0.15 and/or 0.75% dietary levels of supplemented additives increased (P < 0.05) the ileal and duodenal crypt depth, respectively, with a decreased (P < 0.05) duodenal crypt depth at 0.15% dietary level. The goblet cell count in ileum decreased (P < 0.05) in all GLM and oregano EO supplemented groups, but this decreased count (P < 0.05) was detected in jejunum at 0.45 and 0.75% dietary levels. The GLM and oregano EO supplemented groups did not show significant (P > 0.05) changes in the assessed metabolic and immune status parameters. Economically, the total return and performance index was increased at 0.75% dietary level.ConclusionBetter growth performance was achieved at a 0.75 % dietary level of GLM and oregano EO by improving most intestinal morphometric measures. The optimum dietary level detected was 0.58%. The lack of influence of supplemented additives on chickens' immune and metabolic responses could indicate a lack of synergy between GLM and oregano EO.

Effect of alpha-monolaurin on perfomance of fattening pigs under industrial conditions

Relevance. Monoglycerides of organic acids are considered as a promising replacement for feed antibiotics in the diets of pigs and poultry, as they have pronounced bacteriostatic and bactericidal properties. Alpha-monolaurin is a one of the most promising compound, which has a significant antibacterial effect on gram-positive microorganisms.Methods. The experiment was carried out at one of the pig farms of the Rostov region on September 5–27, 2020 on fattening pigs weighing from 36 kg and up to achievinga live weight of 75 kg. Piglets of the experimental group received 0.4 kg/t of alpha-monolaurin as part of the premix for compound feed CK-5. In the conditions of the production site, control weighing was carried out before the beginning and at the end of the experiment. Weight gain, feed consumption, survival rate and feed conversion were recorded.Results. The possibility of using alpha-monoglyceride lauric acid (GML, glycerol monolaurate) in the ration of pigs of the first period of fattening under the industrial conditions of an operating pig farm has been studied. It has been found that alphamonolaurin improves feed conversion, reduces feed intake, and also increases the survival rate of fattening pigs. The use of alpha-monolaurin led to an increase in the economic efficiency of raising pigs by 37.63 rubles/head, or 1:2.38 ROI.

Glycerol Monolaurate Ameliorated Intestinal Barrier and Immunity in Broilers by Regulating Intestinal Inflammation, Antioxidant Balance, and Intestinal Microbiota.

This study was conducted to investigate the impact of glycerol monolaurate (GML) on performance, immunity, intestinal barrier, and cecal microbiota in broiler chicks. A total of 360 one-day-old broilers (Arbor Acres) with an average weight of 45.7 g were randomly allocated to five dietary groups as follows: basal diet and basal diets complemented with 300, 600, 900, or 1200 mg/kg GML. Samples were collected at 7 and 14 days of age. Results revealed that feed intake increased (P < 0.05) after 900 and 1200 mg/kg GML were administered during the entire 14-day experiment period. Dietary GML decreased (P < 0.05) crypt depth and increased the villus height-to-crypt depth ratio of the jejunum. In the serum and jejunum, supplementation with more than 600 mg/kg GML reduced (P < 0.05) interleukin-1β, tumor necrosis factor-α, and malondialdehyde levels and increased (P < 0.05) the levels of immunoglobulin G, jejunal mucin 2, total antioxidant capacity, and total superoxide dismutase. GML down-regulate (P < 0.05) jejunal interleukin-1β and interferon-γ expression and increased (P < 0.05) the mRNA level of zonula occludens 1 and occludin. A reduced (P < 0.05) expression of toll-like receptor 4 and nuclear factor kappa-B was shown in GML-treated groups. In addition, GML modulated the composition of the cecal microbiota of the broilers, improved (P < 0.05) microbial diversity, and increased (P < 0.05) the abundance of butyrate-producing bacteria. Spearman’s correlation analysis revealed that the genera Barnesiella, Coprobacter, Lachnospiraceae, Faecalibacterium, Bacteroides, Odoriacter, and Parabacteroides were related to inflammation and intestinal integrity. In conclusion, GML ameliorated intestinal morphology and barrier function in broiler chicks probably by regulating intestinal immune and antioxidant balance, as well as intestinal microbiota.

Lauric Acid Is a Potent Biological Control Agent That Damages the Cell Membrane of Phytophthora sojae

Sustainable management of plant pathogens is becoming more challenging, and novel solutions are needed. Plant biologically active secondary metabolites are important sources of novel crop protection chemistry. Effective individual compounds of these natural products have the potential to be successful new agrochemicals. In this study, we identified lauric acid (LA) from soybean defense leaf volatiles. LA inhibited the growth of Phytophthora sojae, the causal agent of soybean root rot. It influenced mycelial development, sporangium formation, and zoospore generation and germination by damaging the P. sojae cell membrane. Additionally, we showed that LA and several of its derivatives, such as glycerol monolaurate (GML), had similar biological activities. Both LA and GML were safe to soybean plants when used at less than 0.3 g a.i./plant and could promote soybean growth, implying their potential as eco-friendly biological control agents.

Integrated metabolomic and gene expression analyses to study the effects of glycerol monolaurate on flesh quality in large yellow croaker (Larimichthys crocea)

To improve the quality of cultured large yellow croaker (Larimichthys crocea), this study was performed to study the impacts of glycerol monolaurate (GML) on the nutritional value, growth performance, muscle texture, and taste intensity of L. crocea. The results showed that GML as a feed additive significantly increased the crude lipid content and reduced the diameters of muscle fibers, which in turn markedly altered the flesh texture in terms of cohesiveness. Moreover, the taste indicators (umami and richness) and flavor-related amino acid (glutamic acid, glycine, and proline) contents of L. crocea muscle were significantly higher in the GML group. Metabolomic and gene expression analyses showed that GML supplementation could significantly improve amino acid biosynthesis and metabolism, promote protein and lipid synthesis, and activate myogenic-related signaling pathways of L. crocea. Consequently, adding an appropriate amount of GML to fish feed would be conducive to providing healthy, nutrient-rich and acceptably flavored aquatic-products.

Research Note: Effects of glycerol monolaurate supplementation on egg production, biochemical indices, and gut microbiota of broiler breeders at the late stage of production

The objective of the present study was to determine the effect of glycerol monolaurate (GML) supplementation on egg production, biochemical indices, and gut microbiota of broiler breeders at the late stage of production. Total of 180 healthy Qingyuan Partridge broiler breeders were randomly assigned to 2 groups: 1) corn-soybean meal based diet, and 2) basal diet supplemented with 300 mg glycerol monolaurate/kg. Each treatment group had 6 replicates with 15 birds within each replicate. The experiment started at wk 33 and lasted for 8 weeks. Feed conversion rate, egg weight, egg shape index, shell breaking strength, and shell thickness were not different between control and treatment groups. Supplementation of GML significantly decreased the egg breaking rate. All blood chemical indices and antioxidant parameters were not affected by GML except total antioxidant capacity which increased significantly with GML supplementation. Alpha diversity indices (Shannon, Simpson, Chao1, Ace, goods_coverage, and PD_whole tree) were not different between the 2 groups. Composition of cecal microbiota was not affected by GML supplementation except Euryarchaeota and Proteobacteria at phylum level. Overall, supplementation of glycerol monolaurate at 300 mg/kg level improved eggshell quality but its effect on cecal microbiota composition was limited on broiler breeders at the late stage of production.

Comprehensive evaluation of saturated monoglycerides for the forming of oleogels

To investigate the effect of monoglyceride (MGs) acyl chain length and compounding of MGs on the oleogel properties and stability, 3 different pure MGs and 7 mixtures with different glycerol monostearate (MS): glycerol monobehenate (MB) ratios were studied with high oleic sunflower oil (HOSO) as the liquid oil. The oleogel properties were characterized in terms of structuring potential including oil binding capacity (OBC), hardness and rheological behavior, and the microstructural features associated with these properties determined by differential scanning calorimetry (DSC), solid fat content (SFC), X-ray diffractometry (XRD) and polarized light microscopy (PLM). Changes in oleogel properties (OBC and hardness) and the microstructure during 30 days of storage were also evaluated. Different chain lengths and ratios of MS:MB led to different crystallization rates, polymorphic transitions and aggregation rates, so as to form different crystalline networks and stabilities. In general, the MB oleogel exhibited the highest properties and stability. An increase in OBC in the order of glycerol monolaurate (ML) < MS < MB was observed for pure MG oleogels. The oleogels with mixed MGs outperformed the mechanical properties of the single ones. The best oleogel properties and stabilities were obtained for the oleogel with the MS:MB ratio as 2:8.

Dynamic remodeling of giant unilamellar vesicles induced by monoglyceride nano-micelles: Insights into supramolecular organization

There is broad interest in developing nanostructured assemblies composed of fatty acids and monoglycerides to inhibit membrane-enveloped pathogens and modulate immune cell behavior. Herein, we investigated the interactions of micellar nanostructures composed of a biologically active monoglyceride, glycerol monolaurate (GML), or its ether-bonded equivalent, 1-O-dodecyl-rac-glycerol (DDG), with cell-membrane-mimicking giant unilamellar vesicles (GUVs). Our findings revealed that GML nanostructures induced fission or fusion depending on the GML concentration and corresponding degree of supramolecular organization, while DDG nanostructures only caused aggregation-like disruption of the GUV outer surface. In specific conditions, the GML nanostructures also triggered pearling instability, which led to dynamic membrane remodeling behavior and the pattern of GML interactions was consistent across simplified and complex membrane compositions. Notably, the spectrum of membrane morphological changes induced by GML nanostructures, including fission, fusion, and pearling behaviors, is appreciably wider than the fission behavior exhibited by fatty acid nanostructures in past studies. Collectively, these findings demonstrate how controlling the supramolecular organization of monoglycerides within nanostructured assemblies can be useful to modulate the type and degree of membrane interactions relevant to biophysical and nanomedicine applications.

Use of glycerol monolaurate as a treatment against white spot syndrome virus in crayfish (Procambarus clarkii)

Glycerol monolaurate (GML), a monoester formed from glycerol and lauric acid, is widely used in food, cosmetics, and dietary supplements. GML also has antiviral activity against enveloped viruses. In this study, we conducted a challenge experiment to assess the effects of GML on the survival of crayfish (Procambarus clarkii) infected with white spot syndrome virus (WSSV). Dietary GML treatment reduced the mortality of WSSV-infected crayfish and reduced the WSSV copy number. Quantitative reverse transcriptase polymerase chain reaction analysis showed that GML enhanced the expression of immune-related genes, such as nuclear factor-κB and C-type lectin. GML increased three immune parameters (total hemocyte count, phenoloxidase activity, and superoxide dismutase activity) in crayfish with or without WSSV infection. GML also increased the hemocyte apoptosis rate in crayfish with or without WSSV infection. These data indicated that GML increased hemocyte apoptosis, THC, PO and SOD activity and reduced the mortality in crayfish after oral WSSV challenge, which suggested that GML can be used to keep the crayfish healthy.

Suppression of human T cell activation by derivatives of glycerol monolaurate

Glycerol monolaurate (GML), a naturally occurring monoglyceride, is widely used commercially for its antimicrobial properties. Interestingly, several studies have shown that GML not only has antimicrobial properties but is also an anti-inflammatory agent. GML inhibits peripheral blood mononuclear cell proliferation and inhibits T cell receptor (TCR)-induced signaling events. In this study, we perform an extensive structure activity relationship analysis to investigate the structural components of GML necessary for its suppression of human T cell activation. Human T cells were treated with analogs of GML, differing in acyl chain length, head group, linkage of acyl chain, and number of laurate groups. Treated cells were then tested for changes in membrane dynamics, LAT clustering, calcium signaling, and cytokine production. We found that an acyl chain with 12–14 carbons, a polar head group, an ester linkage, and a single laurate group at any position are all necessary for GML to inhibit protein clustering, calcium signaling, and cytokine production. Removing the glycerol head group or replacing the ester linkage with a nitrogen prevented derivative-mediated inhibition of protein cluster formation and calcium signaling, while still inhibiting TCR-induced cytokine production. These findings expand our current understanding of the mechanisms of action of GML and the of GML needed to function as a novel immunosuppressant.

Physicochemical and antimicrobial properties of chitosan composite films incorporated with glycerol monolaurate and nano-TiO2

Antimicrobial composite films for active food packaging were developed based on chitosan, glycerol monolaurate (GML), and nano-TiO2. The rheological, morphological, physical, and antimicrobial properties of chitosan-based composite films doped with GML and nano-TiO2 were investigated. All film-forming solutions showed typical pseudoplastic properties, and the viscosity of film-forming solutions increased after the addition of GML. The chitosan films incorporated with GML were transparent, and the transparency of films decreased after adding nano-TiO2. The chitosan-TiO2 composite film containing 1.5% GML exhibited the highest UV–vis barrier properties. Scanning electron microscopy images showed that the surface of films containing GML presented a rough structure, and the changes in the microstructure of films were also confirmed by the results obtained using atomic force microscopy. The addition of GML and nano-TiO2 improved the water-resistance and the barrier properties of the chitosan film. Increasing the GML content resulted in increased water contact angle and decreased the permeability of water vapor, oxygen, and carbon dioxide of composite films. Moreover, the incorporation of GML reduced the tensile strength of composite films. Fourier transform infrared spectroscopy and X-ray diffraction indicated that the interaction among chitosan, GML, and nano-TiO2 could be established through non-covalent bonds. Notably, chitosan-based composite films doped with GML and nano-TiO2 exhibited strong antimicrobial activity, and the film containing 1.5% GML was the most effective. The structure of bacterial cells was injured by the composite films. Overall, the developed composite films exhibited excellent functional properties and could be potential targets for bioactive packaging.