Dietary emulsifier polysorbate 80 exposure accelerates age-related cognitive decline.

Gut microbial homeostasis is crucial for the health of cognition in elderly. Previous study revealed that polysorbate 80 (P80) as a widely used emulsifier in food industries and pharmaceutical formulations could directly alter the human gut microbiota compositions. However, whether long-term exposure to P80 could accelerate age-related cognitive decline via gut-brain axis is still unknown. Accordingly, in this study, we used the senescence accelerated mouse prone 8 (SAMP8) mouse model to investigate the effects of the emulsifier P80 intake (1 % P80 in drinking water for 12 weeks) on gut microbiota and cognitive function. Our results indicated that P80 intake significantly exacerbated cognitive decline in SAMP8 mice, along with increased brain pathological proteins deposition, disruption of the blood-brain barrier and activation of microglia and neurotoxic astrocytes. Besides, P80 intake could also induce gut microbiota dysbiosis, especially the increased abundance of secondary bile acids producing bacteria, such as Ruminococcaceae, Lachnospiraceae, and Clostridium scindens. Moreover, fecal microbiota transplantation from P80 mice into 16-week-old SAMP8 mice could also exacerbated cognitive decline, microglia activation and intestinal barrier impairment. Intriguingly, the alterations of gut microbial composition significantly affected bile acid metabolism profiles after P80 exposure, with markedly elevated levels of deoxycholic acid (DCA) in serum and brain tissue. Mechanically, DCA could activate microglial and promote senescence-associated secretory phenotype production through adenosine triphosphate-binding cassette transporter A1 (ABCA1) importing lysosomal cholesterol. Altogether, the emulsifier P80 accelerated cognitive decline of aging mice by inducing gut dysbiosis, bile acid metabolism alteration, intestinal barrier and blood brain barrier disruption as well as neuroinflammation. This study provides strong evidence that dietary-induced gut microbiota dysbiosis may be a risk factor for age-related cognitive decline.

Utilizing chitooligosaccharides from shrimp waste biodegradation via recombinant chitinase A: a promising approach for emulsifying hydrocarbon and bioremediation.

BACKGROUND: Hydrocarbon pollution stemming from petrochemical activities is a significant global environmental concern. Bioremediation, employing microbial chitinase-based bioproducts to detoxify or remove contaminants, presents an intriguing solution for addressing hydrocarbon pollution. Chitooligosaccharides, a product of chitin degradation by chitinase enzymes, emerge as key components in this process. Utilizing chitinaceous wastes as a cost-effective substrate, microbial chitinase can be harnessed to produce Chitooligosaccharides. This investigation explores two strategies to enhance chitinase productivity, firstly, statistical optimization by the Plackett Burman design approach to  evaluating the influence of individual physical and chemical parameters on chitinase production, Followed by  response surface methodology (RSM) which delvs  into the interactions among these factors to optimize chitinase production. Second, to further boost chitinase production, we employed heterologous expression of the chitinase-encoding gene in E. coli BL21(DE3) using a suitable vector. Enhancing chitinase activity not only boosts productivity but also augments the production of Chitooligosaccharides, which are found to be used as emulsifiers. RESULTS: In this study, we focused on optimizing the production of chitinase A from S. marcescens using the Plackett Burman design and response surface methods. This approach led to achieving a maximum activity of 78.65 U/mL. Subsequently, we cloned and expressed the gene responsible for chitinase A in E. coli BL21(DE3). The gene sequence, named SmChiA, spans 1692 base pairs, encoding 563 amino acids with a molecular weight of approximately 58 kDa. This sequence has been deposited in the NCBI GenBank under the accession number "OR643436". The purified recombinant chitinase exhibited a remarkable activity of 228.085 U/mL, with optimal conditions at a pH of 5.5 and a temperature of 65 °C. This activity was 2.9 times higher than that of the optimized enzyme. We then employed the recombinant chitinase A to effectively hydrolyze shrimp waste, yielding chitooligosaccharides (COS) at a rate of 33% of the substrate. The structure of the COS was confirmed through NMR and mass spectrometry analyses. Moreover, the COS demonstrated its utility by forming stable emulsions with various hydrocarbons. Its emulsification index remained stable across a wide range of salinity, pH, and temperature conditions. We further observed that the COS facilitated the recovery of motor oil, burned motor oil, and aniline from polluted sand. Gravimetric assessment of residual hydrocarbons showed a correlation with FTIR analyses, indicating the efficacy of COS in remediation efforts. CONCLUSIONS: The recombinant chitinase holds significant promise for the biological conversion of chitinaceous wastes into chitooligosaccharides (COS), which proved its potential in bioremediation efforts targeting hydrocarbon-contaminated sand.

The essential role of aggregation for the emulsifying ability of a fungal CYS-rich protein.

Biosurfactants are in demand by the global market as natural commodities suitable for incorporation into commercial products or utilization in environmental applications. Fungi are promising producers of these molecules and have garnered interest also for their metabolic capabilities in efficiently utilizing recalcitrant and complex substrates, like hydrocarbons, plastic, etc. Within this framework, biosurfactants produced by two Fusarium solani fungal strains, isolated from plastic waste-contaminated landfill soils, were analyzed. Mycelia of these fungi were grown in the presence of 5% olive oil to drive biosurfactant production. The characterization of the emulsifying and surfactant capacity of these extracts highlighted that two different components are involved. A protein was purified and identified as a CFEM (common in fungal extracellular membrane) containing domain, revealing a good propensity to stabilize emulsions only in its aggregate form. On the other hand, an unidentified cationic smaller molecule exhibits the ability to reduce surface tension. Based on the 3D structural model of the protein, a plausible mechanism for the formation of very stable aggregates, endowed with the emulsifying ability, is proposed. KEY POINTS: • Two Fusarium solani strains are analyzed for their surfactant production. • A cationic surfactant is produced, exhibiting the ability to remarkably reduce surface tension. • An identified protein reveals a good propensity to stabilize emulsions only in its aggregate form.

Production and characterization of extracellular liamocins produced from fungal strains of Aureobasidium spp.

Liamocins, a group of high-density glycolipids, are only produced by certain strains of the yeast-like fungi in the genus Aureobasidium. Until now, few studies have focused on the surfactant properties of liamocins produced from the highly diverse tropical strains of Aureobasidium. Therefore, the aims of this research were to screen the liamocin production from tropical strains of Aureobasidium spp. and to characterize their surfactant properties. A total of 41 strains of Thai Aureobasidium spp. were screened for their ability to produce liamocins, and the products were detected using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thin-layer chromatography. Of those strains, 30 strains of Aureobasidium spp. tested were found to produce liamocins with yields ranging from 0.53 to 10.60 g/l. The nature of all crude liamocins was heterogeneous, with different compositions and ratios depending on the yeast strain. These liamocins exhibited relatively high emulsifying activity against vegetable oils tested, with an emulsification index of around 40-50%; the emulsion stability of some liamocins was up to 30 days. The obtained critical micelle concentration values were varied, with those ​​of liamocins produced from A. pullulans, A. melanogenum and A. thailandense falling in ranges from 7.70 to 119.78, 10.73 to > 1,000, and 68.56 to > 1,000 mg/l, respectively. The emulsification activity of liamocins was higher than that of the analytical grade rhamnolipids. These compounds showed strong surface tension reduction in a sodium chloride concentration range of 2-12% (w/v), pH values between 3 and 7, and temperatures between 4 and 121 °C. This is the first report of liamocins produced by A. thailandense.

Comparison of rumen and abomasal infusions of an exogenous emulsifier on fatty acid digestibility of lactating dairy cows.

We evaluated the effects of infusing an exogenous emulsifier (polysorbates-C18:1) either into the rumen or abomasum on fatty acid (FA) digestibility and production responses of lactating dairy cows. Nine ruminally cannulated multiparous Holstein cows (170 ± 13.6 d in milk) were assigned to a treatment sequence in replicated 3 × 3 Latin squares with 18-d periods consisting of 7 d of washout and 11 d of infusion. Treatments were abomasal infusions of water carrier only into the rumen and abomasum (control, CON), 30 g/d polysorbate-C18:1 (T80) infused into the rumen (RUM), or 30 g/d T80 infused into the abomasum (ABO). Emulsifiers were dissolved in water and delivered at 6-h intervals (total daily infusion was divided into 4 equal infusions per day). Cows were fed the same diet that contained [% diet dry matter (DM)] 32.2% neutral detergent fiber (NDF), 16.1% crude protein, 26.5% starch, and 3.41% FA (including 1.96% FA from a saturated FA supplement containing 28.0% C16:0 and 54.6% C18:0). Two orthogonal contrasts were evaluated: (1) the overall effect of T80 {CON vs. average of the T80 infusions [1/2 (ABO + RUM)]}, and (2) the effect of ABO versus RUM infusion. Compared with CON, infusing T80 increased the digestibilities of NDF (2.85 percentage units), total (4.35 percentage units), 16-carbon (3.25 percentage units), and 18-carbon FA (4.60 percentage units), and tended to increase DM digestibility and total and 18-carbon FA absorption. Compared with RUM, ABO decreased the intakes of total (28 g/d), 16-carbon (7 g/d), and 18-carbon FA (19 g/d); tended to increase the digestibility of total and 18-carbon FA; and had no effect on the absorption of total, 16-carbon, or 18-carbon FA. Production responses did not change among our treatments. In conclusion, infusing 30 g/d polysorbates-C18:1 increased NDF and total, 16-carbon, and 18-carbon FA digestibility. Compared with RUM, ABO tended to increase the digestibilities of total and 18-carbon FA; however, this may be related to the fact that ABO reduced the intakes of total, 16-carbon, and 18-carbon FA, not necessarily due to better emulsifying action per se. In summary, ABO and RUM both improved FA absorption.

Physicochemical and Functional Properties of 2S, 7S, and 11S Enriched Hemp Seed Protein Fractions.

The hemp seed contains protein fractions that could serve as useful ingredients for food product development. However, utilization of hemp seed protein fractions in the food industry can only be successful if there is sufficient information on their levels and functional properties. Therefore, this work provides a comparative evaluation of the structural and functional properties of hemp seed protein isolate (HPI) and fractions that contain 2S, 7S, or 11S proteins. HPI and protein fractions were isolated at pH values of least solubility. Results showed that the dominant protein was 11S, with a yield of 72.70 ± 2.30%, while 7S and 2S had values of 1.29 ± 0.11% and 3.92 ± 0.15%, respectively. The 2S contained significantly (p < 0.05) higher contents of sulfhydryl groups at 3.69 µmol/g when compared to 7S (1.51 µmol/g), 11S (1.55 µmol/g), and HPI (1.97 µmol/g). The in vitro protein digestibility of the 2S (72.54 ± 0.52%) was significantly (p < 0.05) lower than those of the other isolated proteins. The intrinsic fluorescence showed that the 11S had a more rigid structure at pH 3.0, which was lost at higher pH values. We conclude that the 2S fraction has superior solubility, foaming capacity, and emulsifying activity when compared to the 7S, 11S, and HPI.

An overview of fungal biopolymers: bioemulsifiers and biosurfactants compounds production.

Fungal biopolymers have gained considerable attention from the scientific community for various applications due to their biological and physicochemical properties. The wide applications in several areas, especially in the food industry as a bioemulsifier and in the agricultural area as a biosurfactant, have expanded the knowledge on the production of fungal biopolymers to keep up with developments on this subject area. Recent scientific studies have disclosed novel routes, optimized parameters, increased yields, and other related approaches in order to produce and apply fungal bioemulsifiers and biosurfactants. However, there is a need to gather important information in order to provide a way forward. Therefore, this review presents an overview of properties, applications, and perspectives for encouraging further projects and investments in the near future by most categories of investors. The selection of culture media, the definition of cultivation parameters, extraction, recovery, and purification are the initial steps to indicate the conditions for scale-up. Indeed, scale-up is still one of the challenges in this biotechnological field, which could be solved by expanding the tests and operational productions in both pilot and industrial plants.

Low-resolution molecular shape, biochemical characterization and emulsification properties of a halotolerant esterase from Bacillus licheniformis.

Bacterial esterases are highly versatile enzymes, currently widely used in detergents, biosurfactants, bioemulsifiers and as biocatalysts in paper and food industries. Present work describes heterologous expression, purification, and biophysical and biochemical characterization of a halotolerant esterase from Bacillus licheniformis (BlEstA). BlEstA preferentially cleaves pNP-octanoate and both activity and stability of the enzyme increased in the presence of 2 M NaCl, and also with several organic solvents (ethanol, methanol and DMSO). Furthermore, BlEstA has considerable emulsifying properties, particularly with olive oil as substrate. Our studies also show that the enzyme is monomeric in solution and its small-angle X-ray scattering low-resolution molecular envelope fits well its high-resolution homology model.

Biofunctionality of Enzymatically Derived Peptides from Codfish (Gadus morhua) Frame: Bulk In Vitro Properties, Quantitative Proteomics, and Bioinformatic Prediction.

Protein hydrolysates show great promise as bioactive food and feed ingredients and for valorization of side-streams from e.g., the fish processing industry. We present a novel approach for hydrolysate characterization that utilizes proteomics data for calculation of weighted mean peptide properties (length, molecular weight, and charge) and peptide-level abundance estimation. Using a novel bioinformatic approach for subsequent prediction of biofunctional properties of identified peptides, we are able to provide an unprecedented, in-depth characterization. The study further characterizes bulk emulsifying, foaming, and in vitro antioxidative properties of enzymatic hydrolysates derived from cod frame by application of Alcalase and Neutrase, individually and sequentially, as well as the influence of heat pre-treatment. All hydrolysates displayed comparable or higher emulsifying activity and stability than sodium caseinate. Heat-treatment significantly increased stability but showed a negative effect on the activity and degree of hydrolysis. Lower degrees of hydrolysis resulted in significantly higher chelating activity, while the opposite was observed for radical scavenging activity. Combining peptide abundance with bioinformatic prediction, we identified several peptides that are likely linked to the observed differences in bulk emulsifying properties. The study highlights the prospects of applying proteomics and bioinformatics for hydrolysate characterization and in food protein science.

Abomasal infusion of an exogenous emulsifier improves fatty acid digestibility and milk fat yield of lactating dairy cows.

The objective of our study was to determine the effects of abomasal infusion of an emulsifier on fatty acid (FA) digestibility and production responses of lactating dairy cows. Eight rumen-cannulated cows (109 ± 18 d in milk) were randomly assigned to a treatment sequence in replicated 4 × 4 Latin squares with 18-d periods including 7 d of washout and 11 d of infusion with sampling on the last 4 d. Treatments were abomasal infusions of water carrier only (CON) and 3 levels of increasing doses of Tween 80 (polysorbate 80, Tween 80, Sigma-Aldrich, St. Louis, MO) delivering 15 (D-15), 30 (D-30), and 45 (D-45) g/d. The Tween 80 was dissolved in water before infusions, which were delivered at 6-h intervals. Cows were fed the same diet, which contained (% dry matter) 31% neutral detergent fiber, 17% crude protein, 25% starch, and 4% FA (2% dry matter from a saturated fat supplement containing 33% C16:0 and 51% C18:0). Increasing emulsifier infusion dose quadratically increased digestibility of total FA (60.7, 65.3, 70.9, and 66.8%), 16-carbon FA (61.7, 63.9, 70.4, and 66.7%), and 18-carbon FA (59.8, 65.6, 71.1, and 66.6%, respectively). Increasing emulsifier infusion dose quadratically increased absorbed total FA (625, 670, 744, and 658 g/d), 16-carbon FA (151, 157, 197, and 157 g/d, quadratic), and 18-carbon FA (420, 460, 500, and 444 g/d). Increasing emulsifier infusion dose tended to quadratically decrease dry matter intake (29.0, 28.8, 29.6, and 27.6 kg/d). Increasing emulsifier infusion dose quadratically increased milk fat content (3.23, 3.35, 3.45, and 3.35%), milk fat yield (1.54, 1.61, 1.65, and 1.55 kg/d), ECM (45.7, 46.9, 47.5, and 45.3 kg/d), and plasma nonesterified fatty acid concentration (95.6, 98.4, 101.2, and 98.6 µEq/L). On a yield basis, we observed that de novo, mixed, and preformed FA responded quadratically to Tween 80 infusion due to FA yield increasing up to D-30. Treatments had no effect on milk yield (47.9, 48.3, 48.0, and 46.6 kg/d). In conclusion, short-term infusion of an exogenous emulsifier improved FA digestibility and milk fat yield responses when cows were fed a diet containing a saturated fat supplement. Most digestion and production measurements responded quadratically because the highest dose of exogenous emulsifier (45 g/d) decreased dry matter intake and performance.

Geobacillus strains that have potential value in microbial enhanced oil recovery.

Bacteria from the genus Geobacillus are generally obligately thermophilic, with a unique bioenergy production capacity and unique enzymes. Geobacillus species were isolated primarily from hot springs, oilfields, and associated soils. They often exhibit unique survival patterns in these extreme oligotrophic environments. With the development of the microbial resources found in oilfields, Geobacillus spp. have been proven as valuable bacteria in many reports related to oilfields. After the isolation of Geobacillus by culture methods, more evidence was found that they possess the abilities of hydrocarbon utilization and bioemulsifier production. This paper mainly summarizes some characteristics of the Geobacillus species found in the oilfield environment, focusing on the inference and analysis of hydrocarbon degradation and bioemulsifier synthesis based on existing research, which may reveal their potential value in microbial enhanced oil recovery. It also provides references for understanding microbes in extreme environments.

Application of Pickering Emulsion with Cyclodextrin as an Emulsifier to a Transdermal Drug Delivery Vehicle.

The emulsion prepared with ß-cyclodextrin as an emulsifier (ßCDE) is considered to be a Pickering emulsion. We examined the characteristics of ßCDEs using captopril (CP) as a model drug, and studied the in vitro skin permeation of CP from ßCDEs through hairless mouse skin. The stability of ßCDE was increased with increasing ßCD concentration and conversely decreased with increasing CP concentration. The yield stress value from the rheological measurement results was suggested to be one of the factors determining the stability of the ßCDE, and ßCDEs with higher yield stress values were more stable. We found that the skin permeability of CP could be improved by using ßCDE with isopropyl myristate as the oil phase and that the flux of CP depended on the free CP concentration in the water phase of ßCDE.

Production and properties of a bioemulsifier obtained from a lactic acid bacterium.

In the present work, the production of bioemulsifier (BE) by a lactic acid bacterium (LAB) grown at 25 °C in lactic whey-based media for 24 h was evaluated. Maximum production was detected in a medium containing yeast extract, peptone and lactic whey (LAPLW medium), with a yield of 270 mg L-1. The BE proved to be more innocuous for Caco-2 cells, used as a toxicological indicator, than the non-ionic surfactant Triton X-100. In addition, the microbial product presented higher stability to changes in temperature (37 °C to 100 °C), pH (2-10), and salt concentration (5% and 20%, w/v) than the synthetic surfactant. Regarding emulsifying capacity tested against different hydrophobic substrates (kerosene, motor oil, diesel, sunflower oil, and grape oil), the BE displayed E24 values similar to or even better than those of Triton X-100. Finally, Triton X-100 caused irreversible modifications on the giant unilamellar vesicles (used as model membrane system), promoting the solubilization of the lipid bilayers. Nevertheless, BE induced temporary modifications of the membrane, which is associated with incorporation of the bioproduct in the outer layer. These results demonstrate the role of BE in biological processes, including reversible changes in microbial membranes to enhance the access to hydrophobic substrates.

Production, characterization, and applications of bioemulsifiers (BE) and biosurfactants (BS) produced by Acinetobacter spp.: A review.

Bioemulsifiers (BE) and biosurfactants (BS) are considered as multifunctional biomolecules of 21st century because of their functional abilities and eco-friendly properties. They are produced by various microorganisms under versatile and extreme environmental conditions. They have tremendous applications in various industries such as petroleum, food, medicine, pharmaceutical, chemical, paper & pulp, textile, and cosmetics. Currently, they are also considered as "green molecules" because of their wide applications in bioremediation of soil. Their importance has been increasing day by day in the global market as they are the natural resources with high-aggregate value. Although, there are numerous reports on BE and BS production by different bacteria, Acinetobacter spp. acquired special attention among all. This is because it is the earliest member known for the production of bioemulsifier. Emulsan and Alasan are the best examples of the commercially used BE produced by Acinetobacter spp. These BE are mainly used in microbial enhanced oil recovery and biodegradation of toxic compounds. This review is focused on BE and BS produced by Acinetobacter spp., their characterization and applications in different fields. This is the first review on genus Acinetobacter which defines independently about different types of BE and BS produced by it. It will also address the need of exploration of these molecules from various sources and their applications for the benefit of mankind and sustainable environment.

Mechanism of enhanced oral absorption of akebia saponin D by a self-nanoemulsifying drug delivery system loaded with phospholipid complex.

Akebia saponin D (ASD) exhibits a variety of pharmacological activities, such as anti-osteoporosis, neuroprotection, hepatoprotection, but has poor oral bioavailability. A self-nanoemulsifying drug delivery system loaded with akebia saponin D - phospholipid complex (APC-SNEDDS) (composition: Peceol: Cremophor® EL: Transcutol HP: ASD: phospholipid; ratio: 10:45:45:51:12.3, w:w:w:w:w) was first developed to improve the oral absorption of saponins and it was found to significantly enhance ASD's oral bioavailability by 4.3 - fold (p < .01). This study was conducted to elucidate the mechanism of enhanced oral absorption of ASD by the drug delivery system of APC-SNEDDS. The aggregation morphology and particle size of ASD and APC-SNEDDS prepared in aqueous solutions were determined by transmission electron microscope and particle size analyzer, respectively. Stability of ASD and APC-SNEDDS in gastrointestinal luminal contents and mucosa homogenates were also explored. The differences of in situ intestinal permeability of ASD and APC-SNEDDS were compared. APC-SNEDDS reduced the aggregation size from 389 ± 7 nm (ASD) to 148 ± 3 nm (APC-SNEDDS). APC-SNEDDS increased the remaining drug in large intestine luminal contents from 47 ± 1% (ASD) to 83 ± 1% (APC-SNEDDS) during 4 h incubation. APC-SNEDDS provided an 11-fold increase in Ka value and an 11-fold increase in Peff value compared to ASD. In summary, APC-SNEDDS improved ASD's oral bioavailability mainly by increasing membrane permeability, destroying self-micelles and inhibiting the intestinal metabolism.

Self-Nanoemulsifying Drug Delivery System (SNEDDS) for Improved Oral Bioavailability of Chlorpromazine: In Vitro and In Vivo Evaluation.

Background and Objectives: Lipid-based self-nanoemulsifying drug delivery systems (SNEDDS) have resurged the eminence of nanoemulsions by modest adjustments and offer many valuable opportunities in drug delivery. Chlorpromazine, an antipsychotic agent with poor aqueous solubility-with extensive first-pass metabolism-can be a suitable candidate for the development of SNEDDS. The current study was designed to develop triglyceride-based SNEDDS of chlorpromazine to achieve improved solubility, stability, and oral bioavailability. Materials and Methods: Fifteen SNEDDS formulations of each short, medium, and long chain, triglycerides were synthesized and characterized to achieve optimized formulation. The optimized formulation was characterized for several in vitro and in vivo parameters. Results: Particle size, zeta potential, and drug loading of the optimized SNEDDS (LCT14) were found to be 178 ± 16, -21.4, and 85.5%, respectively. Long chain triglyceride (LCT14) showed a 1.5-fold increased elimination half-life (p < 0.01), up to 6-fold increased oral bioavailability, and 1.7-fold decreased plasma clearance rate (p < 0.01) compared to a drug suspension. Conclusion: The findings suggest that SNEDDS based on long-chain triglycerides (LCT14) formulations seem to be a promising alternative for improving the oral bioavailability of chlorpromazine.

Acinetobacter soli SP2 Capable of High-Efficiency Degradation of Food Emulsifier Polysorbate 80.

Emulsifiers like polysorbate family, carboxymethyl cellulose are widely used in the preparation of drugs, vaccines, food, cosmetics, and skin care products. In this study, strain SP2 is isolated for the high-efficiency utilization of emulsifier as its sole carbon and energy source. Strain grows on the polysorbate family with generation time ranging from 0.8 to 2.2 h. It is sensitive to ampicillin, gentamicin, imipenem, penicillin, and vancomycin, but resistant to amikacin, cefoxitin, erythromycin, kanamycin, nalidixic acid, and tetracycline. Based on 16S rRNA gene, strain is identified as Acinetobacter soli. Compared to M. pamicella, which is capable of degrading 50% polysorbate 80 within 3 days, isolate PS2 could dispose 51.6% polysorbate 80 within only 8 h. Using cell crude extract from strain SP2, the liberation of free fatty acid in the reaction mixture containing polysorbate 80 suggests that the mechanism for polysorbate utilization belongs to the ß-oxidation.

Metabolic effects in mice of cream formulation: Addition of both thickener and emulsifier does not alter lipid metabolism but modulates mucus cells and intestinal endoplasmic reticulum stress.

Additives stabilize or improve the organoleptic or functional properties (or both) of many dairy products including whipping cream. Their influence on the metabolic effect of dairy cream is scarcely known. We tested the hypothesis that added emulsifier (lactic acid esters of mono- and diglycerides; MAG/DAG), thickener (carrageenan, CGN), or both, could modify the metabolic effect, notably in the intestine and liver. Nine-week-old male C57Bl/6J mice were fed UHT cream (indirect treatment) mixed with nonlipidic powder (final: 13% milkfat) for 1 or 4 wk. We compared creams (1) without additive (Ctl), (2) with thickener (Th), 0.02% of κ-CGN, and (3) with both thickener and emulsifier, 0.1% of MAG/DAG esters (Th/Em). We analyzed plasma parameters, intestine, and liver. Fasting glycemia, insulinemia, triglyceridemia, nonesterified fatty acids, body weight gain, and liver weight did not differ among groups. After 1 wk, Th/Em had higher expression in the duodenum of some of the genes involved in (1) intestinal lipid absorption and (2) tight junction proteins versus Ctl and Th. After 4 wk, mucus cell number in the small intestine was higher in Th/Em versus Ctl and Th. Genes involved in endoplasmic reticulum (ER) stress in the duodenum were more expressed in Th/Em after 1 wk. After 4 wk, in the colon, a higher expression of ER stress genes was observed for Th versus Th/Em and Ctl. Liver damage score was not altered by additives. Adding both CGN (0.02%) and MAG/DAG esters (0.1%) in dairy cream did not result in deleterious outcomes in mice after 4 wk regarding lipid metabolism, intestinal permeability, and liver disorders. The longer term effect of intestinal ER stress modulation deserves further investigation.

Stable bioemulsifiers are produced by Acinetobacter bouvetii UAM25 growing in different carbon sources.

Acinetobacter species are identified as producing surface-active and emulsifying molecules known as bioemulsifiers. Production, characterization and stability of bioemulsifiers produced by Acinetobacter bouvetii UAM25 were studied. A. bouvetii UAM25 grew in three different carbon and energy sources: ethanol, a glycerol-hexadecane mixture and waste cooking oil in an airlift bioreactor, showing that bioemulsifier production was growth associated. The three purified bioemulsifiers were lipo-heteropolysaccharides of high molecular weight (4866 ± 533 and 462 ± 101 kDa). The best carbon source and energy for bioemulsifier production was wasted cooking oil, with a highest emulsifying capacity (76.2 ± 3.5 EU mg-1) as compared with ethanol (46.6 ± 7.1 EU mg-1) and the glycerol-hexadecane mixture (49.5 ± 4.2 EU mg-1). The three bioemulsifiers in our study displayed similar macromolecular structures, regardless of the nature (hydrophobic or hydrophilic) of the carbon and energy source. Bioemulsifiers did not decrease surface tension, but the emulsifying capacity of all of them was retained under extreme variation in salinity (0-50 g NaCl L-1), pH (3-10) and temperature (25-121 °C), indicative of remarkable stability. These findings contribute to understanding of the relationship between: production, physical properties, chemical composition and stability of bioemulsifiers for their potential applications in biotechnology, such as bioremediation of hydrocarbon-contaminated soil and water.

Haererehalobacter sp. JS1, a bioemulsifier producing halophilic bacterium isolated from Indian solar salt works.

Bioemulsifier (BE)-producing Haererehalobacter sp. JS1 was isolated and identified from the solar salt works in India. The BE was extracted, purified, and characterized by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Emulsification activity was performed against different oils and dye degradation potential against different dyes. The production of BE was optimized using different carbon sources (C), nitrogen sources (N), pH, and NaCl. BE screening methods revealed that, Haererehalobacter sp. JS1 was highly positive BE production. Identification by 16S rRNA sequencing and analyses was found that, the Haererehalobacter sp. JS1 was closely related to Salinicoccus halophilus and Haererehalobacter sp. The structural characterization analysis confirmed that the partially purified bioemulsifier belongs to siloxane-type. Emulsification activity (E24) revealed that the bioemulsifier significantly (p < = 0.001) emulsified the commercial oils including coconut oil, gingelly oil, olive oil, and palmolein oils. Haererehalobacter sp. JS1 also significantly (p < = 0.001) degraded the dyes such as orange MR, direct violet, cotton red, reactive yellow, nitro green, and azo dye. RSM regression co-efficient and contour plot analysis clearly indicated that the combination of pH and NaCl helped to increase BE production. Siloxane-type of BE obtained from Haererehalobacter sp. JS1 was able to emulsify different oils and commercial dyes.