Monolaurin Research Articles

Synergistic antimicrobial activity of lynronne-1 and EDTA against bovine mastitis pathogens.

Bovine mastitis is the costliest disease in the dairy sector and the main cause of antibiotic use in dairy cattle, potentially contributing to the antimicrobial resistance crisis. Antimicrobial peptides (AMPs) offer promise as antibiotic alternatives for controlling mastitis pathogens. The efficacy of five AMPs (Lynronne-1 [Lyn-1], Lynronne-2 [Lyn-2], Bovicin HC5, AMP 660, and AMP 1043) and two bioactive compounds (disodium ethylenediaminetetraacetic acid [EDTA] and glycerol monolaurate) was assessed against a range of 35 mastitis-causing pathogens. The fractional inhibitory concentrations index (FICI) was calculated to determine the interaction effect and values ≤0.5 were indicative of synergism. Time-dependent killing assays were performed to assess bactericidal efficacy of the combination. Cytotoxicity was evaluated using the MTT assay and haemolytic activity was assessed against fresh bovine erythrocytes. Lyn-1 and EDTA exhibited the highest broad spectrum antimicrobial activity and reduced bacterial growth (OD600 nm) by 95.1% and 86.9%, respectively. FICI values ranged from 0.1 to 0.5, indicating synergism. The combination of lyn-1 (0.03 mg/mL) and EDTA (1.02 mg/mL) exhibited higher antimicrobial activity against all bacterial strains, at significantly lower concentrations than each compound individually. Lyn-1-EDTA combination reduced viable population by >10 000-fold within 12 h. The combination was non-haemolytic in concentrations up to 8-fold the established MIC values (P > 0.05), although cytotoxic effects were observed at concentrations above MIC (P < 0.01). These findings highlight the therapeutic potential of Lyn-1 and Lyn-1-EDTA for developing antibiotic-free formulations to combat contagious and environmental mastitis pathogens and treat udder infections.

Medium-chain fatty acid triglycerides improve feed intake and oxidative stress of finishing bulls by regulating ghrelin concentration and gastrointestinal tract microorganisms and rumen metabolites

BackgroundAs a feed additive, medium-chain fatty acids (MCFAs)/medium-chain fatty acid triglycerides (MCTs) have been used in ruminant production, but mostly added in the form of mixed esters. Studies have shown that MCTs may have a positive effect on feed intake or oxidative stress in animals, but it is unclear which MCT could play a role, and the mechanism has not been elucidated. In this study, the effects of individual MCT on growth performance, serum intake-related hormones, and oxidative stress indices in finishing bulls were investigated and further studied the effects of MCT supplementation on gastrointestinal tract bacteria and rumen fluid metabolomics.ResultsFour ruminally fistulated Yanbian cattle (bulls) were selected in 4 × 4 Latin square designs and allocated to four treatment groups: a control group (CON) fed a basal diet (total mixed ration, TMR), three groups fed a basal diet supplemented with 60 g/bull/day glycerol monocaprylin (GMC, C8), glycerol monodecanoate (GMD, C10), and glycerol monolaurate (GML, C12), respectively. Compared with the CON group, GMD tended to increase the dry matter intake (DMI) of finishing bulls (P = 0.069). Compared with the CON group, GMD significantly increased the concentration of ghrelin O-acyl transferase (GOAT), total ghrelin (TG), acylated ghrelin (AG), and orexins (P < 0.05) and significantly decreased the concentrations of hydrogen peroxide (H2O2), malondialdehyde, reactive oxygen species (ROS), and lipopolysaccharides (LPS) in the serum of finishing bulls (P < 0.05). Compared with the CON group, GMD and GML significantly increased the concentrations of total antioxidant capacity (T-AOC), catalase, glutathione peroxidase (GSH-PX), glutathione reductase (GR), and nitric oxide (NO) in the serum of finishing bulls (P < 0.05). Compared with the CON group, there were 5, 14, and 6 significantly different bacteria in the rumen digesta in the C8, C10, and C12 groups, respectively; there were 3, 10, and 5 significantly different bacteria in the rumen fluid in the C8, C10, and C12 groups, respectively; and only one differential bacteria (genus level) in the feces among the four treatment groups. Compared with the CON group, there were 3, 14, and 15 significantly differential metabolites identified under positive ionization mode in the C8, C10, and C12 groups, respectively, while under negative ionization mode were 3, 11 and 14, respectively. Correlation analysis showed that there was a significant correlation between DMI, GOAT, AG, GSH-PX, LPS, gastrointestinal tract bacteria, and rumen fluid metabolites.ConclusionsOur findings revealed that different types of MCTs have different application effects in ruminants. Among them, GMD may improve the feed intake of finishing bulls by stimulating the secretion of AG. GMD and GML may change gastrointestinal tract microorganisms and produce specific rumen metabolites to improve the oxidative stress of finishing bulls, and ghrelin may also be involved. This study enlightens the potential mechanisms by which MCT improves feed intake and oxidative stress in finishing bulls.5d9kULzJFQsQ3ajLfa--XDVideo

Effect of glycerol monolaurate nanocapsules on Streptococcus mutans biofilm in vitro

This study aimed to prepare and apply nanocapsules containing glycerol monolaurate for eradicating Streptococcus mutans biofilms. The interfacial deposition method of the preformed polymer synthesized the nanocapsules characterized for mean diameter, polydispersity index, zeta potential, pH, and morphology by transmission electron microscopy. The microdilution method investigated antimicrobial activity. Crystal violet staining determined biomass quantification and the ability to inhibit biofilm formation. The study also measured exopolysaccharide production and the number of viable colonies. The characterization outcomes indicated acceptable values for the mean diameter 198.1 ± 2, a polydispersity index of 0.087 ± 0.018, a zeta potential of -21.30 ± 2.00 mV, a pH of 6.19 ± 0.12, and typical nanostructure morphology. The evaluations of minimum inhibitory and bactericidal concentrations of glycerol monolaurate (free and nanoencapsulated) revealed their ineffectiveness in inhibiting microorganisms. Only free glycerol monolaurate inhibits S. mutans growth with 125 µg/mL. Biomass, exopolysaccharide content, and viable colonies in the biofilm were analyzed to assess the compounds' ability to inhibit biofilm formation. The tested compounds did not significantly reduce the formed biofilm. Despite unfavorable outcomes of the formulated preparation, further experimentation with a new formulation is encouraged to explore alternative strategies and potential improvements.

Effect of dietary glycerol monolaurate supplementation on gene expression, intestinal mucosa and microbiota of juvenile black sea bream (Acanthopagrus schlegelii).

Glycerol monolaurate (GML) is a chemical compound derived from the combination of lauric acid and glycerol, exhibiting potent antimicrobial properties. An eight-week feeding trial was conducted to evaluate the effects of dietary supplementation of Glycerol Monolaurate (GML) on juvenile black sea bream. The control diet included 24% fish meal, while five additional diets were formulated with increasing GML concentrations: 0.01% (GML1), 0.02% (GML2), 0.04% (GML3), 0.08% (GML4), and 0.16% (GML5). Each diet was assigned to triplicate tanks. At the end of the experiment, serum immune and antioxidant in liver were non-significantly different among the groups. The relative gene expression of IGF-1 and GH in liver was statistically higher in the GML3 treated. The relative gene expression of IL-1, TGF, TNF-1, CCK, CLDN1, CASS-3 and GPR41 in intestine were statistically higher in the GML3 group. The photomicrographs of transmission electron microscope of the intestine were also studied. The GML supplemented groups had longer brush borders. The cells seemed to be joined by an intact junctional complex without visible intercellular spaces. The observed variations in phyla, class, and genus did not demonstrate statistical significance. Proteobacteria, Cyanobacteria, Firmicutes and Actinobacteria in the phylum, and Oxyphotobacteria, Bacteroidia, Holophagae and Negativicutes in the class, Brevundimonas, and Achromobacter in the genera were all substantially increased with higher levels of GML supplementation. Based on these results, it is suggested that glycerol monolaurate (GML) may serve as a potential dietary supplement for promoting different gene expression and intestinal health in black sea bream.

Effect of Dietary Supplementation of Glycerol Monolaurate on Growth Performance, Digestive Enzymes, Serum Immune and Antioxidant Parameters, and Intestinal Morphology in Black Sea Bream.

An eight-week feeding trial was conducted to examine the impact of dietary supplementation with glycerol monolaurate (GML) on juvenile black sea bream. A basal diet was formulated containing 24% fish meal, while five additional diets were prepared, each supplemented with varying levels of GML: GML1 (0.01%), GML2 (0.02%), GML3 (0.04%), GML4 (0.08%), and GML5 (0.16%). Triplicate tanks were randomly allocated to each diet, each containing 20 fish with an initial weight of 1.55 ± 0.05 g. By the trial's end, the GML3 group displayed a notably higher final body weight (FBW), weight gain (WG), specific growth rate (SGR), and protein efficiency ratio (PER) compared to the other groups (p < 0.05), but the FCR was significantly higher in the control group. However, no significant differences were observed in the MFI, PPV, CF, HSI, IPF, VSI, or SR among the groups (p > 0.05). Regarding the proximate compositions of the dorsal muscle and whole body, no substantial differences were observed across the groups (p > 0.05). Additionally, there were no significant variations in digestive enzyme activity (p > 0.05), serum immune, or biochemical parameters in the midgut and hindgut among the treatment groups. But in the serum immune response IgM, C3 and C4 were significantly higher in the GML3 group as compared to the other groups (p < 0.05). However, the GML3 group exhibited significantly greater fore-intestinal villus height, crypt depth, villus height per crypt depth, and the number of goblet cells per villus compared to the other groups (p < 0.05). Overall, GML supplementation, particularly GML3, significantly improved growth indicators like the final body weight and intestinal morphology. While certain parameters remained unaffected, these findings suggest GML's potential as a beneficial dietary supplement in fish diets.

Fabrication of novel polysaccharides and glycerol monolaurate based camellia oil composite oleogel: Application in wound healing promotion

In this study, a novel camellia oil composite oleogel (SX@G-CO) was prepared by a combination of direct dispersion and emulsion-templated methods using polysaccharides (sodium alginate and xanthan gum, ratio in 4:6) as oleogelators and glycerol monolaurate (GML, 7 wt%) as gel-enhancer. The comparative experiments revealed that the polysaccharides could effectively enhance the densification of the three-dimensional network structure of the oleogel through hydrogen bonding and electrostatic interactions, and significantly improve its thermal stability, rheological properties (adhesive strength 49,243.6 mPa•s, viscosity recovery rate 94.6 %) and oil binding capacity (80.6 %). The introduction of GML further enriched the crystal diversity of the oleogel and imparted excellent antimicrobial ability (nearly 100 % inhibition effect on E.coli). Furthermore, the in vitro experiments demonstrated that the synergistic effect of polysaccharides and GML significantly enhanced the anti-inflammatory, antioxidant, cell migration and proliferation abilities of SX@G-CO oleogel compared with GML-CO and SX-CO oleogels. In addition, SX@G-CO oleogel has also been demonstrated to effectively promote full-thickness burn healing in mice by reducing bacterial infection and inflammatory response, regulating free radical levels, and promoting neovascularization in vivo, with effects comparable to marketed ointment. SX@G-CO oleogel as a bioactive molecule-polysaccharides composite has potential clinical application in burn wound repair.

Antimicrobial effect of lactoferrin and glycerol monolaurate on selected bacteria associated with newborn infections

Human breast milk contains a rich array of bioactive substances, such as immunoglobulins, lactoferrin antimicrobial peptides, and glycerol monolaurate, which play a crucial role in providing immune protection to infants. Infant formula manufacturers strive to match mother's milk's nutritional makeup, including immune-boosting ingredients. Lactoferrin and glycerol monolaurate (GML) are important antibacterial compounds in human milk. The study aimed to investigate the effect of bovine lactoferrin (bLf) and GML in preventing the growth of inoculated bacteria into infant formula. The study examined both individual and combined use of these components. The bacteria that were tested included: 1) Gram-negative bacteria: Cronobacter sakazakii strains 12868 and 29004, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, and 2) Gram-positive bacteria: Methicillin-resistant Staphylococcus aureus (MRSA), and Listeria monocytogenes. The result of the agar diffusion assays showed that bLf, at a concentration of 16 mg/disc, exhibited strong inhibition (≥20 mm) of all the selected bacterial strains. On the other hand, GML at a concentration of 8 mg/disc showed strong inhibition of all strains; however, Gram-positive bacteria were more susceptible, so a concentration of 5 mg/disc was enough to achieve strong inhibition of these strains. The minimal bactericidal concentrations (MBC) analysis aimed to achieve a >3-log reduction in the growth of various bacterial strains. The results showed that S. enterica Typhimurium and L. monocytogenes were more susceptible to bLf than the other strains (MBC: 7 and 4.8 mg/ml, respectively, vs. 14.9–18.4 mg/ml for the other strains). In contrast, MRSA and L. monocytogenes were more susceptible to GML (MBC: 6 and 10 mg/ml, respectively, vs. 16–18 mg/ml for Gram-negative strains). The results of reconstituted powdered infant formulas (RPIF), with the addition of bLf, GML, or both at pathogen-specific MBC, showed significant log reductions in the growth of experimentally inoculated bacteria compared to the control at different time intervals. All bacterial strains exposed to bLf and GML exhibited >3-log reduction within 72 h, with Gram-positive strains showing >7-log reduction. GML and bLf combined had a stronger anti-bacterial activity than individual components, indicating the potential of combining GML and bLf as natural agents against specific pathogenic bacteria. Future studies are needed to understand the potential use of these compounds in different food matrices and clinical settings.

Development and antimicrobial activity of composite edible films of chitosan and nisin incorporated with perilla essential oil-glycerol monolaurate emulsions

Aquatic products are highly susceptible to spoilage, and preparing composite edible film with essential oil is an effective solution. In this study, composite edible films were prepared using perilla essential oil (PEO)-glycerol monolaurate emulsions incorporated with chitosan and nisin, and the film formulation was optimized by response surface methodology. These films were applied to ready-to-eat fish balls and evaluated over a period of 12 days. The films with the highest inhibition rate against Staphylococcus aureus were acquired using a polymer composition of 6 μL/mL PEO, 18.4 μg/mL glycerol monolaurate, 14.2 mg/mL chitosan, and 11.0 μg/mL nisin. The fish balls coated with the optimal edible film showed minimal changes in appearance during storage and significantly reduced total bacterial counts and total volatile basic nitrogen compared to the control groups. This work indicated that the composite edible films containing essential oils possess ideal properties as antimicrobial packaging materials for aquatic foods.

Preparation of soybean protein isolate–ester emulsifier oleogels and comparative study of their structure and properties

In recent years, oleogel as a viscoelastic semi-solid to replace trans fatty acids and reduce saturated fatty acids in food has received more and more attention. Herein, an emulsion template method was used to produce soybean oil–based oleogels with seven different ester emulsifiers and soy protein isolate as oleogelators. The chemical and physical characteristics of oleogels produced via various crosslinking factors were comparatively examined. Results revealed that all oleogels generated β-type needle crystals and exhibited high oil-holding capacity (>80 %), among which glycerol monolaurate G2 and diacetyl tartaric acid ester of mono–diglycerides G6 exhibited the strongest oil-holding capacity (96.6 % and 96.2 %, respectively). Furthermore, all oleogels exhibited strong thixotropic recovery, high thermal stability, as well as high gel strength (G′ > G′′). Of these, G2 and G6 exhibited the highest thixotropic recovery rates at 74.54 % and 78.19 %, respectively. Additionally, in accelerated oxidation trials, the peroxide value and thiobarbituric acid reactive substances of all oleogels had low oxidation rates, indicating high oxidative stability. These results contribute to a better understanding of oleogels for formulating trans-free and low-saturated foodstuffs with desired physical and functional properties.

The Impact of Beeswax and Glycerol Monolaurate on Camellia Oil Oleogel's Formulation and Application in Food Products.

This study assessed the nutritional profile of camellia oil through its fatty acid composition, highlighting its high oleic acid content (81.4%), followed by linoleic (7.99%) and palmitic acids (7.74%), demonstrating its excellence as an edible oil source. The impact of beeswax (BW) and glycerol monolaurate (GML) on camellia oil oleogels was investigated, revealing that increasing BW or GML concentrations enhanced hardness and springiness, with 10% BW oleogel exhibiting the highest hardness and springiness. FTIR results suggested that the structure of the oleogels was formed by interactions between molecules without altering the chemical composition. In biscuits, 10% BW oleogel provided superior crispness, expansion ratio, texture, and taste, whereas GML imparted a distinct odor. In sausages, no significant differences were observed in color, water retention, and pH between the control and replacement groups; however, the BW group scored higher than the GML group in the sensory evaluation. The findings suggest that the BW oleogel is an effective fat substitute in biscuits and sausages, promoting the application of camellia oil in food products.

Micellar-type aggregates of HP-β-CD/GML inclusion complex: Increased water-solubility and effective antibacterial capabilities

The inclusion complex (IC) was successfully obtained by encapsulating glycerol monolaurate (GML) into the cavity of hydroxypropyl-β-cyclodextrin (HP-β-CD). Compared with solubility of pure GML <80 μg/mL in water, and the water-solubility of encapsulated GML was significantly improved and reached to 270,000 μg/mL. IC can form nanoparticles by self-assembly, probably assigned to its strong capability to form micellar-type aggregates. A Higuchi's AL-type phase-solubility diagram indicated the strong interaction between host and guest molecules with the formation of 1:1 GML/HP-β-CD complex and the stability constant at 6248 L/mol. Compared with pure GML, encapsulated GML at the same concentration can also show good antibacterial capabilities against S. aureus and E. coli in sterile water, and the effective preservative capabilities towards beef meatballs. The boosted enhancement in water-solubility of GML and the effective antibacterial capabilities endowed IC with potential in the application of food decontamination.

Glycerol monolaurate extracts protective effects in Caco-2 cells and dextran sulfate sodium-induced colitis in C57BL/6 mice

Glycerol monolaurate (GML) is a common food additive known for its antimicrobial and anti-inflammatory properties. This study aims to assess the impact of GML on experimental colitis, both in vivo and in vitro. The results indicated that GML significantly inhibited the expression of MIP-3α, TNF-α, IL-1β, and IL-6, while upregulating the expression of claudin-3 and claudin-4 in DSS-treated Caco-2 cell monolayers. Oral administration of GML effectively alleviated colitis in mice, as demonstrated by mitigating body weight loss, lowering the DAI score, and improving colon shrinkage. GML significantly suppressed the expression of NF-κB p65, IL-1β, IL-6, TNF-α, and IL-18 in DSS-treated mice. Moreover, GML increased the cecal microbial alpha-diversity index and restored the dysbiosis. GML significantly increased the relative abundance of Lactobacillus, Alistipes, and Bacteroides, which were found to be negatively correlated with the DAI score and pro-inflammatory cytokine expression. In conclusion, the results highlight the potential therapeutic benefits of GML in preventing colitis and emphasize the role of gut microbiota in this process.

Effects of dietary glycerol monolaurate on growth and digestive performance, lipid metabolism, immune defense and gut microbiota of shrimp (Penaeus vannamei)

The advancement of the Penaeus vannamei industry in a sustainable manner necessitates the creation of eco-friendly and exceptionally effective feed additives. To achieve this, 720 similarly-sized juvenile shrimp (0.88 ± 0.02 g) were randomly divided into four groups in this study, with each group consisting of three replicates, each tank (400 L) containing 60 shrimp. Four experimental diets were formulated by adding 0, 500, 1000, and 1500 mg kg−1 glycerol monolaurate (GML) to the basal diet, and the feeding trial lasted for 42 days. Subsequently, a 72-h White Spot Syndrome Virus (WSSV) challenge test was conducted. Polynomial orthogonal contrasts analysis revealed that with the increase in the concentration of GML, those indicators related to growth, metabolism and immunity, exhibit linear or quadratic correlations (P < 0.05). The results indicate that the GML groups exhibited a significant improvement in the shrimp weight gain rate, specific growth rate, and a reduction in the feed conversion ratio (P < 0.05). Furthermore, the GML groups promoted the lipase activity and reduced lipid content of the shrimp, augmented the expression of triglyceride and fatty acid decomposition-related genes and lowered the levels of plasma triglycerides (P < 0.05). GML can also enhanced the humoral immunity of the shrimp by activating the Toll-like receptor and Immune deficiency immune pathways, improved the phagocytic capacity and antibacterial ability of shrimp hemocytes. The challenge test revealed that GML significantly reduced the mortality of the shrimp compared to control group. The 16S rRNA sequencing indicates that the GML group can increases the abundance of beneficial bacteria. However, 1500 mg kg−1 GML adversely affected the stability of the intestinal microbiota, significantly upregulating intestinal antimicrobial peptide-related genes and tumor necrosis factor-alpha levels (P < 0.05). In summary, 1000 mg kg−1 GML was proven to enhance the growth performance, lipid absorption and metabolism, humoral immune response, and gut microbiota condition of P. vannamei, with no negative physiological effects.

Glycerol monolaurate regulates apoptosis and inflammation by suppressing lipopolysaccharide-induced ROS production and NF-κB activation in avian macrophages

Macrophages play a crucial role in both innate and adaptive immunity. However, their abnormal activation can lead to undesirable inflammatory reactions. This study aimed to investigate the effects of glycerol monolaurate (GML), a natural monoester known for its anti-inflammatory and immunoregulatory properties, on avian macrophages using the HD11 cell line. The results indicated that a concentration of 10 μg/mL of GML enhanced the phagocytic activity of HD11 cells (P < 0.05) without affecting cell viability (P > 0.05). GML decreased the expression of M1 macrophage polarization markers, such as CD86 and TNF-α genes (P < 0.05), while increasing the expression of M2 macrophage polarization markers, such as TGF-β1 and IL-10 genes (P < 0.05). GML suppressed ROS production, apoptosis, and the expression of proinflammatory genes (IL-1β and IL-6) induced by LPS (P < 0.05). GML also promoted the expression of TGF-β1 and IL-10 (P < 0.05), both in the presence and absence of LPS exposure. Moreover, GML suppressed the gene expression of TLR4 and NF-κB p65 induced by LPS (P < 0.05), as well as the phosphorylation of NF-κB p65 (P < 0.05). In conclusion, GML exhibited regulatory effects on the polarized state of avian macrophages and demonstrated significant anti-apoptotic and anti-inflammatory properties by suppressing intracellular ROS and the NF-κB signaling pathway.

PSV-11 In vitro screening of selected compounds to reduce ruminal methane production

Abstract Methane is a natural product of rumen fermentation and emissions from ruminant livestock represent a major environmental concern. Methane is not only a potent greenhouse gas but also represents a loss of energy efficiency for the host. The objective of this study was to perform in vitro screening of a range of compounds with potential anti-methanogenic activity, including polyphenols, flavonoids, fatty acids, amino acids, and salts. We aimed to select compounds conferring up to a 20% reduction in CH4 for further investigations. The substances tested included carvacrol, coumaric acid, coumarin, flavanone, gallic acid, glycerol monolaurate (GML), glycine, methylene blue, naringin, quercetin, quinic acid, resorcinol, rutin, tannic acid, vanillic acid, and zinc acetate. These substances varied in their mechanisms of action and were selected based on known antimicrobial or anti-methanogenic properties. The experiment was designed as a randomized block experiment, with treatments tested in triplicates across four batches (n = 228 samples) using the same treatments and experimental conditions. Fresh rumen contents were manually collected from two rumen-fistulated lactating Holstein cows, 3 h after their morning feeding. Rumen contents were blended at a 2:1 ratio, filtered through a four-layered cheesecloth, and added to McDougall’s solution at a 2:1 ratio. Final media (9 mL) was added to a 20 mL Bellco flask containing 150 mg of total mixed ration (TMR) ground to 1 mm. Each batch also had three flasks without TMR and no treatment (blank flasks), three flasks containing only TMR without treatment (negative control), and three flasks containing TMR and treated with chloroform (positive control), resulting in a total of 19 treatments. The end-products of in vitro batch fermentations were assessed after 24 h of incubation, and samples from each flask were collected for gas composition analysis using gas chromatography. Volatile fatty acids were determined using high-performance liquid chromatography (HPLC). The data were analyzed using R Studio, and the following model was applied: yij = µ + treatmenti + batchj + ℇij. Methane production (measured in parts per million, ppm) increased when GML, naringin, and quercetin were added compared with the negative control. In contrast, the addition of carvacrol, glycine, tannic acid, and methylene blue resulted in a decrease of up to 25% in methane production. These compounds show potential to alter ruminal fermentation and mitigate methane production and will be selected for evaluation of synergistic interactions and effects on the rumen microbial communities.

PSV-17 Glycerol monolaurate improves litter performance and modifies milk composition when fed to lactating sows

Abstract Glycerol monolaurate (GML) has proven antibacterial, antiviral and anti-inflammatory properties, and additionally has been shown to increase milk immunoglobulins and improve gut health. However, limited information is available on how feeding GML to the sow prior and during lactation can influence the performance of the nursing pig. The objective of this study was to determine if feeding GML to sows would help maintain body condition, increase lauric acid in milk and improve litter performance. A total of 50 sows were randomly assigned to either a control feed or to a control feed with 1.5 kgs/mT of GML (LipoVital GL-90) 3 to 5 dbefore farrowing. Sow and litter performance was measured until weaning at 25 d. On d 1, piglets were cross-fostered within treatment and weighed. Creep feed was offered. Milk samples were taken from 5 randomly selected sows per treatment on d 3 and 25. Glycerol monolaurate had no effect on number of pigs born alive, born dead, stillborn, or number weaned (P &amp;gt; 0.20). No treatment differences (P &amp;gt; 0.20) were observed for sow feed intake, loss of backfat thickness or body weight losses during the study. Control piglets tended to consume more creep feed than GML piglets (P &amp;lt; 0.15). Starting body weight was less for GML piglets (P &amp;lt; 0.001). Despite the decreased starting body weight, weaning weight was not different between treatments (P &amp;gt; 0.20). Using starting body weight as a covariate, total body weight gain tended to be greater (P &amp;lt; 0.08) for GML piglets than the control piglets (5.01 kgs vs 4.89 kg, respectively). Glycerol monolaurate-fed pigs in the bottom quartile of starting body weights (&amp;lt; 1.3 kgs) numerically out gained their control counterparts (4.67 kgs vs 4.12 kgs). Milk from GML sows had 57% more lauric acid on d 3 (P &amp;lt; 0.05) and 124% more lauric acid at weaning compared with control sows (P &amp;lt; 0.05). In conclusion, GML maintained sow body condition, increased the content of lauric acid in milk and improved piglet body weight gain, especially in lighter body weight piglets. The results from this study demonstrate the application of GML in commercial sow herds will be beneficial to both sow and litter.

Effects of glycerol monolaurate on estradiol and follicle-stimulating hormones, offspring quality, and mRNA expression of reproductive-related genes of zebrafish (Danio rerio) females.

This study aims to explore whether glycerol monolaurate (GML) can improve reproductive performance of female zebrafish (Danio rerio) and the survival percentage of their offspring. Three kinds of isonitrogenous and isolipid diets, including basal diet (control) and basal diet containing 0.75g/kg GML (L_GML) and 1.5g/kg GML (H_GML), were prepared for 4weeks feeding trial. The results show that GML increased the GSI of female zebrafish. GML also enhanced reproductive performance of female zebrafish. Specifically, GML increased spawning number and hatching rate of female zebrafish. Moreover, GML significantly increased the levels of triglycerides (TG), lauric acid, and estradiol (E2) in the ovary (P < 0.05). Follicle-stimulating hormone (FSH) levels in the ovary and brain also significantly increased in the L_GML group (P < 0.05). Besides, dietary GML regulated the hypothalamus-pituitary-gonad (HPG) axis evidenced by the changed expression levels of HPG axis-related genes in the brain and ovary of the L_GML and H_GML groups compared with the control group. Furthermore, compared with the control group, the expression levels of HPG axis-related genes (kiss2, kiss1r, kiss2r, gnrh3, gnrhr1, gnrhr3, lhβ, and esr2b) in the brain of the L_GML group were significantly increased (P < 0.05), and the expression levels of HPG axis-related genes (kiss1, kiss2, kiss2r, gnrh2, gnrh3, gnrhr4, fshβ, lhβ, esr1, esr2a, and esr2b) in the brain of the H_GML group were significantly increased (P < 0.05). These results suggest that GML may stimulate the expression of gnrh2 and gnrh3 by increasing the expression level of kiss1 and kiss2 genes in the hypothalamus, thus promoting the synthesis of FSH and E2. The expression levels of genes associated with gonadotropin receptors (fshr and lhr) and gonadal steroid hormone synthesis (cyp11a1, cyp17, and cyp19a) in the ovary were also significantly upregulated by dietary GML (P < 0.05). The increasing expression level of cyp19a also may promote the FSH synthesis. Particularly, GML enhanced the richness and diversity and regulated the species composition of intestinal microbiota in female zebrafish. Changes in certain intestinal microorganisms may be related to the expression of certain genes involved in the HPG axis. In addition, L_GML and H_GML both significantly decreased larvae mortality at 96h post fertilization and their mortality during the first-feeding period (P < 0.05), revealing the enhanced the starvation tolerance of zebrafish larvae. In summary, dietary GML regulated genes related to HPG axis to promote the synthesis of E2 and FSH and altered gut microbiota in female zebrafish, and improved the survival percentage of their offspring.

Complete kinetic model for esterification reaction of lauric acid with glycerol to synthesize glycerol monolaurate

Glycerol monolaurate (GML) is a widely used industrial chemical with excellent emulsification and antibacterial effect. The direct esterification of glycerol with lauric acid is the main method to synthesize GML. In this work, the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst. A complete kinetic model of consecutive esterification reaction has been established, and the kinetic equation of acid catalysis was deduced. The isomerization reactions of GML and glycerol dilaurate were investigated. It was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification reaction. The kinetic equations of the consecutive esterification reaction were obtained by experiments as k1=(276+92261Xcat)exp(−37720/RT) and k2=(80+4413Xcat)exp(−32240/RT). The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.

Unlocking glycerol monolaurate potential: A comprehensive review of synthesis pathways, catalyst insights, and optimization strategies

Glycerol monolaurate (GML) is a versatile green chemical with wide industrial applicability, including in the food, pharmaceutical, and personal care product industries. This review provides a thorough analysis of the processes involved in GML production, along with the diverse applications of GML. And also, addresses various limitations and challenges associated with esterification of lauric acid with glycerol to produce GML through enzymatic, homogeneous, and heterogeneous catalytic pathways. Among these routes, heterogeneous catalytic routes exhibited superior catalytic activity, achieving over 90% selectivity with good stability. Furthermore, the review offers a constructive assessment of the process parameters associated with catalysts and reaction conditions that influence the GML yield and selectivity. Notably, wide pore and short pore length were found to be suitable for attaining higher selectivity in esterification of lauric acid. Techno-economic assessments suggest that the enzyme route is more environmentally sustainable. However, in practice, the heterogeneous catalytic route proves more suitable for industrial-scale production. Therefore, this review may provide crucial guidance for researchers and industries aiming to produce GML in an economic and eco- friendly manner.

Enhanced stability and antibacterial efficacy of edible oleogels-in-water high internal phase emulsions prepared from soybean lipophilic protein

Recently, convenience-driven consumers have increasingly embraced prepared aquatic foods, facilitating a significant shift within the food industry. However, this change has presented a challenge for maintaining the quality of aquatic products in prepared food items since aquatic products are highly susceptible to microbial contamination during processing or storage. Herein, smart oleogels-in-water high internal phase emulsions (GHIPEs) stabilized solely by soybean lipophilic protein (LP) were prepared via oil phase gelation induced by glycerol monolaurate (GML). The purpose of this system is to act as an effective carrier and facilitate the precise release of thyme essential oils to extend the shelf life of food products. The gelation of the oil phase has significantly enhanced the stability of GHIPEs when compared to traditional HIPEs. When the GML reached 2%, the GHIPEs retained up to 87.18% ± 4.23 of thyme essential oil after 14 d. Moreover, the highest antioxidant potential of GHIPEs (with 2% GML) was confirmed through DPPH and ABTS free radical scavenging assays. Furthermore, the GHIPEs can release thyme essential oil in response to microbial growth, demonstrating their “smart sensing and targeted release” ability. Ultimately, the application of the GHIPEs in the preservation of Cololabis saira significantly reduced the total colony count, pH, TVB-N, and TBARS values (P < 0.05). Consequently, a ready-to-eat Cololabis saira product with an extended shelf life of 7 d at 4 °C was successfully realized, indicating the effectiveness of GHIPEs in preserving seafood freshness. These findings offer novel approaches to maintaining the freshness of prepared aquatic foods.