RESUMEN
Antimicrobial fatty acids derived from natural sources and renewable feedstocks are promising surface-active substances with a wide range of applications. Their ability to target bacterial membrane in multiple mechanisms offers a promising antimicrobial approach for combating bacterial infections and preventing the development of drug-resistant strains, and it provides a sustainable strategy that aligns with growing environmental awareness compared to their synthetic counterparts. However, the interaction and destabilization of bacterial cell membranes by these amphiphilic compounds are not yet fully understood. Here, we investigated the concentration-dependent and time-dependent membrane interaction between long-chain unsaturated fatty acids-linolenic acid (LNA, C18:3), linoleic (LLA, C18:2), and oleic acid (OA, C18:1)-and the supported lipid bilayers (SLBs) using quartz crystal microbalance-dissipation (QCM-D) and fluorescence microscopy. We first determined the critical micelle concentration (CMC) of each compound using a fluorescence spectrophotometer and monitored the membrane interaction in real time following fatty acid treatment, whereby all micellar fatty acids elicited membrane-active behavior primarily above their respective CMC values. Specifically, LNA and LLA, which have higher degrees of unsaturation and CMC values of 160 µM and 60 µM, respectively, caused significant changes in the membrane with net |Δf| shifts of 23.2 ± 0.8 Hz and 21.4 ± 0.6 Hz and ΔD shifts of 5.2 ± 0.5 × 10-6 and 7.4 ± 0.5 × 10-6. On the other hand, OA, with the lowest unsaturation degree and CMC value of 20 µM, produced relatively less membrane change with a net |Δf| shift of 14.6 ± 2.2 Hz and ΔD shift of 8.8 ± 0.2 × 10-6. Both LNA and LLA required higher concentrations than OA to initiate membrane remodeling as their CMC values increased with the degree of unsaturation. Upon incubating with fluorescence-labeled model membranes, the fatty acids induced tubular morphological changes at concentrations above CMC. Taken together, our findings highlight the critical role of self-aggregation properties and the degree of unsaturated bonds in unsaturated long-chain fatty acids upon modulating membrane destabilization, suggesting potential applications in developing sustainable and effective antimicrobial strategies.
Asunto(s)
Antiinfecciosos , Micelas , Ácidos Grasos , Membrana Dobles de Lípidos/química , Antiinfecciosos/farmacología , Ácido OléicoRESUMEN
The addition of Bifidobacterium to goat milk has dual effects on health, for which various inherent nutrients of goat milk are retained and live probiotics are provided. We explored the effect of Bifidobacterium animalis ssp. lactis Probio-M8 (Probio-M8) on fermentation characteristics, formation of organic acid, sensory properties, and storage characteristics of fermented goat milk (with added 4.0% sucrose). Addition of Probio-M8 decreased the fermentation time and significantly increased the content of functional organic acids, such as acetic acid, and functional long-chain unsaturated fatty acids, including linoleic acid, α-linolenic acid, and docosahexaenoic acid. Furthermore, the contents of medium-chain and short-chain fatty acids, which are related to "goaty" flavor, were significantly lower in the Probio-M8 treatment compared with the control. The number of living Probio-M8 decreased from 8.27 log cfu/mL (1.80 × 108 cfu/mL) to 7.94 log cfu/mL (0.79 × 108 cfu/mL) after 28 d of storage. Titratable acidity and pH value did not differ between the control group and experimental group (containing Probio-M8). Sensory evaluation indicated a lower goaty flavor and odor in the Probio-M8 fermented milk. Our results suggest that the addition of the probiotic Probio-M8 could improve the sensory, physicochemical, and functional properties of fermented goat milk.
Asunto(s)
Bifidobacterium animalis , Probióticos , Animales , Bifidobacterium animalis/metabolismo , Leche/química , Probióticos/metabolismo , Bifidobacterium/metabolismo , Fermentación , Ácidos Grasos/metabolismo , Cabras/metabolismoRESUMEN
BACKGROUND: The forkhead box O3a protein (FoxO3a) has been reported to be involved in the migration and invasion of trophoblast, but its underlying mechanisms unknown. In this study, we aim to explore the transcriptional and metabolic regulations of FoxO3a on the migration and invasion of early placental development. METHODS: Lentiviral vectors were used to knock down the expression of FoxO3a of the HTR8/SVneo cells. Western blot, matrigel invasion assay, wound healing assay, seahorse, gas-chromatography-mass spectrometry (GC-MS) based metabolomics, fluxomics, and RNA-seq transcriptomics were performed. RESULTS: We found that FoxO3a depletion restrained the migration and invasion of HTR8/SVneo cells. Metabolomics, fluxomics, and seahorse demonstrated that FoxO3a knockdown resulted in a switch from aerobic to anaerobic respiration and increased utilization of aromatic amino acids and long-chain fatty acids from extracellular nutrients. Furthermore, our RNA-seq also demonstrated that the expression of COX-2 and MMP9 decreased after FoxO3a knockdown, and these two genes were closely associated with the migration/invasion progress of trophoblast cells. CONCLUSIONS: Our results suggested novel biological roles of FoxO3a in early placental development. FoxO3a exerts an essential effect on trophoblast migration and invasion owing to the regulations of COX2, MMP9, aromatic amino acids, energy metabolism, and oxidative stress.
Asunto(s)
Proteína Forkhead Box O3/metabolismo , Preeclampsia , Trofoblastos , Aminoácidos Aromáticos/metabolismo , Línea Celular , Movimiento Celular/genética , Femenino , Humanos , Metaloproteinasa 9 de la Matriz/metabolismo , Placenta/metabolismo , Preeclampsia/genética , Embarazo , Trofoblastos/metabolismoRESUMEN
Long chain unsaturated fatty acids (LCUFAs) are important food components and dietary supplements due to their beneficial health effects. The key process to produce high-purity LCUFAs is to separate long chain fatty acids (LCFAs) with different degrees of unsaturation and chain lengths. This process faces great challenge because of similar physico-chemical properties of fatty acids concerned. In this work, fractional extraction is proposed to separate LCFAs, using eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), conjugated linoleic acids (CLAs), oleic acid (OA) and stearic acid (SA) as model LCFAs. COSMO-RS calculations were performed for fast extractant screening and exploring the potential separation mechanism. Satisfactory distribution coefficients and high selectivities were obtained in extraction equilibrium experiments. Simulation and experimental validation of fractional extraction were performed, and high purity and high yield of CLAs were obtained. EPA and DHA could be separated thoroughly from OA, though they could not be separated each other.