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Saussurea laniceps is a traditional medicinal herb. In our previous study, a pectin polysaccharide, SLP-4, was isolated from the petals of S. laniceps. In this study, the immunomodulatory activity of SLP-4 was studied by analyzing its effects on macrophage (RAW 264.7 cells) polarization. The immunomodulatory activity assays indicated that SLP-4 could significantly enhance the pinocytic and phagocytic capacity and promote the expression and secretion of cytotoxic molecules (nitric oxide, increased by 6.4 times when the SLP-4 concentration was 800 µg/mL) and cytokines (tumor necrosis factor-α and interleukin-6 increased by 7.7 and 11.9 times, respectively) in original macrophage. The possible mechanism could be attributed to the activation of the mitogen-activated protein kinase and nuclear factor-κB signaling pathways through Toll-like receptors 2 and 4. Moreover, SLP-4 significantly induced M1 polarization of original macrophages and transferred macrophages from M2 to M1, but had little effect on the conversion of M1 macrophages into M2 phenotype. Overall, these results demonstrate the potential of SLP-4 as an attractive immunomodulating functional supplement.
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INTRODUCTION: Thalassemia represents a significant public health challenge globally. However, the global burden of thalassemia and the disparities associated with it remain poorly understood. Our study aims to uncover the long-term spatial and temporal trends in thalassemia at global, regional, and national levels, analyze the impacts of age, time periods, and birth cohorts, and pinpoint the global disparities in thalassemia burden. METHODS: We extracted data on the thalassemia burden from the Global Burden of Disease Study (GBD) 2019. We employed a joinpoint regression model to assess temporal trends in thalassemia burden and an age-period-cohort model to evaluate the effects of age, period, and cohort on thalassemia mortality. RESULTS: From 1990 to 2019, the number of thalassemia incident cases, prevalent cases, mortality cases, and disability-adjusted life years (DALYs) decreased by 20.9%, 3.1%, 38.6%, and 43.1%, respectively. Age-standardized rates of incidence, prevalence, mortality, and DALY declined across regions with high, high-middle, middle, and low-middle sociodemographic index (SDI), yet remained the highest in regions with low SDI and low-middle SDI as well as in Southeast Asia, peaking among children under five years of age. The global prevalence rate was higher in males than in females. The global mortality rate showed a consistent decrease with increasing age. CONCLUSION: The global burden of thalassemia has significantly declined, yet notable disparities exist in terms of gender, age groups, periods, birth cohorts, SDI regions, and GBD regions. Systemic interventions that include early screening, genetic counseling, premarital health examinations, and prenatal diagnosis should be prioritized in regions with low, and low-middle SDI, particularly in Southeast Asia. Future population-based studies should focus specifically on thalassemia subtypes and transfusion requirements, and national registries should enhance data capture through newborn screening.
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Carga Global de Enfermedades , Talasemia , Humanos , Talasemia/epidemiología , Talasemia/mortalidad , Carga Global de Enfermedades/tendencias , Masculino , Femenino , Niño , Preescolar , Adolescente , Prevalencia , Lactante , Incidencia , Adulto , Salud Global/estadística & datos numéricos , Adulto Joven , Recién Nacido , Años de Vida Ajustados por Discapacidad , Costo de Enfermedad , Tasa de SupervivenciaRESUMEN
AIMS: Caused by multiple risk factors, heavy burden of major depressive disorder (MDD) poses serious challenges to public health worldwide over the past 30 years. Yet the burden and attributable risk factors of MDD were not systematically known. We aimed to reveal the long-term spatio-temporal trends in the burden and attributable risk factors of MDD at global, regional and national levels during 1990-2019. METHODS: We obtained MDD and attributable risk factors data from Global Burden of Disease Study 2019. We used joinpoint regression model to assess the temporal trend in MDD burden, and age-period-cohort model to measure the effects of age, period and birth cohort on MDD incidence rate. We utilized population attributable fractions (PAFs) to estimate the specific proportions of MDD burden attributed to given risk factors. RESULTS: During 1990-2019, the global number of MDD incident cases, prevalent cases and disability-adjusted life years (DALYs) increased by 59.10%, 59.57% and 58.57%, respectively. Whereas the global age-standardized incidence rate (ASIR), age-standardized prevalence rate (ASPR) and age-standardized DALYs rate (ASDR) of MDD decreased during 1990-2019. The ASIR, ASPR and ASDR in women were 1.62, 1.62 and 1.60 times as that in men in 2019, respectively. The highest age-specific incidence, prevalence and DALYs rate occurred at the age of 60-64 in women, and at the age of 75-84 in men, but the maximum increasing trends in these age-specific rates occurred at the age of 5-9. Population living during 2000-2004 had higher risk of MDD. MDD burden varied by socio-demographic index (SDI), regions and nations. In 2019, low-SDI region, Central sub-Saharan Africa and Uganda had the highest ASIR, ASPR and ASDR. The global PAFs of intimate partner violence (IPV), childhood sexual abuse (CSA) and bullying victimization (BV) were 8.43%, 5.46% and 4.86% in 2019, respectively. CONCLUSIONS: Over the past 30 years, the global ASIR, ASPR and ASDR of MDD had decreased trends, while the burden of MDD was still serious, and multiple disparities in MDD burden remarkably existed. Women, elderly and populations living during 2000-2004 and in low-SDI regions, had more severe burden of MDD. Children were more susceptible to MDD. Up to 18.75% of global MDD burden would be eliminated through early preventing against IPV, CSA and BV. Tailored strategies-and-measures in different regions and demographic groups based on findings in this studywould be urgently needed to eliminate the impacts of modifiable risk factors on MDD, and then mitigate the burden of MDD.
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Trastorno Depresivo Mayor , Carga Global de Enfermedades , Salud Global , Humanos , Trastorno Depresivo Mayor/epidemiología , Factores de Riesgo , Carga Global de Enfermedades/tendencias , Femenino , Masculino , Incidencia , Salud Global/estadística & datos numéricos , Adulto , Prevalencia , Persona de Mediana Edad , Análisis Espacio-Temporal , Anciano , Años de Vida Ajustados por Discapacidad/tendencias , Adulto Joven , Costo de Enfermedad , AdolescenteRESUMEN
The instability of ester bonds, low water solubility, and increased cytotoxicity of flavonoid glycoside esters significantly limit their application in the food industry. Therefore, the present study attempted to resolve these issues through liposome encapsulation. The results showed that baicalin butyl ester (BEC4) and octyl ester (BEC8) have higher encapsulation and loading efficiencies and lower leakage rate from liposomes than baicalin. FTIR results revealed the location of BEC4 and BEC8 in the hydrophobic layer of liposomes, which was different from baicalin. Additionally, liposome encapsulation improved the water solubility and stability of BEC4 and BEC8 in the digestive system and PBS but significantly reduced their cytotoxicity. Furthermore, the release rate of BEC4 and BEC8 from liposomes was lower than that of baicalin during gastrointestinal digestion. These results indicate that liposome encapsulation alleviated the negative effects of fatty chain introduction into flavonoid glycosides.
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Ésteres , Flavonoides , Liposomas , Flavonoides/química , Flavonoides/farmacología , Flavonoides/administración & dosificación , Liposomas/química , Humanos , Ésteres/química , Solubilidad , Supervivencia Celular/efectos de los fármacos , Composición de MedicamentosRESUMEN
In this study, we developed a multi-site acylation strategy to improve the lipophilicity and cellular uptake of troxerutin, a natural flavonoid with many health-promoting bioactivities. By clarifying the acylation properties of troxerutin catalyzed by lipases from different sources, a series of troxerutin ester derivatives acylated at different sites was synthesized, including troxerutin dipropyl (TDP), tripropyl (TTP), tetrapropyl (TEP), dibutyl (TDB), monohexyl (TMH), monooctyl (TMO) and monodecyl (TMD) esters. Interestingly, the troxerutin esters acylated at multiple sites with shorter fatty chains (TDP, TTP and TEP) had similar lipophilicity to the mono-acylated esters bearing longer fatty chains (TMH, TMO and TMD, respectively) and meanwhile demonstrated surprisingly lower cytotoxicity than that of the long fatty-chain mono-esters. In particular, the multi-acylated esters with shorter fatty chains showed remarkably higher cellular uptake than the mono-esters with long fatty chains. In vitro gastrointestinal digestion suggested that the multi-acylated esters of troxerutin were more resistant to gastrointestinal degradation than the mono-esters. These results indicated that multi-site acylation with short fatty chains could be an effective alternative to introducing one-site mono-acylation for the modification of troxerutin and other flavonoid compounds.
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Hidroxietilrutósido , Lipasa , Acilación , Humanos , Hidroxietilrutósido/análogos & derivados , Hidroxietilrutósido/farmacología , Hidroxietilrutósido/química , Hidroxietilrutósido/metabolismo , Lipasa/metabolismo , Lipasa/química , AnimalesRESUMEN
A novel yeast-mediated hydrogenation was developed for the synthesis of neohesperidin dihydrochalcone (NHDC) in high yields (over 83%). Moreover, whole-cell catalytic hydrolysis was also designed to hydrolyze NHDC into potential sweeteners, hesperetin dihydrochalcone-7-O-glucoside (HDC-G) and hesperetin dihydrochalcone (HDC). The biohydrogenation was further combined with whole-cell hydrolysis to achieve a one-pot two-step biosynthesis, utilizing yeast to hydrogenate CâC in the structure, while Aspergillus niger cells hydrolyze glycosides. The conversion of NHDC and the proportion of hydrolysis products could be controlled by adjusting the catalysts, the components of the reaction system, and the addition of glucose. Furthermore, yeast-mediated biotransformation demonstrated superior reaction stability and enhanced safety and employed more cost-effective catalysts compared to the traditional chemical hydrogenation of NHDC synthesis. This research not only provides a new route for NHDC production but also offers a safe and flexible one-pot cascade biosynthetic platform for the production of high-value compounds from citrus processing wastes.
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Chalconas , Hesperidina , Hesperidina/análogos & derivados , Saccharomyces cerevisiae , Hidrólisis , Saccharomyces cerevisiae/metabolismo , Estudios de Factibilidad , Hesperidina/química , BiotransformaciónRESUMEN
The exploration of the physical attributes of the recently discovered orthocarbonate Sr3CO5 is significant for comprehending the carbon cycle and storage mechanisms within the Earth's interior. In this study, first-principles calculations are initially used to examine the structural phase transitions of Sr3CO5 polymorphs within the range of lower mantle pressures. The results suggest that Sr3CO5 with the Cmcm phase exhibits a minimal enthalpy between 8.3 and 30.3 GPa. As the pressure exceeds 30.3 GPa, the Cmcm phase undergoes a transition to the I4/mcm phase, while the experimentally observed Pnma phase remains metastable under our studied pressure. Furthermore, the structural data of SrO, SrCO3, and Sr3CO5 polymorphs are utilized to develop a deep learning potential model suitable for the Sr-C-O system, and the pressure-volume relationship and elastic constants calculated using the potential model are in line with the available results. Subsequently, the elastic properties of Cmcm and I4/mcm phases in Sr3CO5 at high temperature and pressure are calculated using the molecular dynamics method. The results indicate that the I4/mcm phase exhibits higher temperature sensitivity in terms of elastic moduli and wave velocities compared to the Cmcm phase. Finally, the thermodynamic properties of the Cmcm and I4/mcm phases are predicted in the range of 0-2000 K and 10-120 GPa, revealing that the heat capacity and bulk thermal expansion coefficient of both phases increase with temperature, with the constant volume heat capacity gradually approaching the Dulong-Petit limit as the temperature rises.
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Rapid eye movement (REM) sleep is the main sleep correlate of dreaming. Ponto-geniculo-occipital (PGO) waves are a signature of REM sleep. They represent the physiological mechanism of REM sleep that specifically limits the processing of external information. PGO waves look just like a message sent from the pons to the lateral geniculate nucleus of the visual thalamus, the occipital cortex, and other areas of the brain. The dedicated visual pathway of PGO waves can be interpreted by the brain as visual information, leading to the visual hallucinosis of dreams. PGO waves are considered to be both a reflection of REM sleep brain activity and causal to dreams due to their stimulation of the cortex. In this review, we summarize the role of PGO waves in potential neural circuits of two major theories, i.e., (1) dreams are generated by the activation of neural activity in the brainstem; (2) PGO waves signaling to the cortex. In addition, the potential physiological functions during REM sleep dreams, such as memory consolidation, unlearning, and brain development and plasticity and mood regulation, are discussed. It is hoped that our review will support and encourage research into the phenomenon of human PGO waves and their possible functions in dreaming.
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Background: The immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are crucial in maintaining a delicate balance between protective effects and harmful pathological reactions that drive the progression of coronavirus disease 2019 (COVID-19). T cells play a significant role in adaptive antiviral immune responses, making it valuable to investigate the heterogeneity and diversity of SARS-CoV-2-specific T cell responses in COVID-19 patients with varying disease severity. Methods: In this study, we employed high-throughput T cell receptor (TCR) ß repertoire sequencing to analyze TCR profiles in the peripheral blood of 192 patients with COVID-19, including those with moderate, severe, or critical symptoms, and compared them with 81 healthy controls. We specifically focused on SARS-CoV-2-associated TCR clonotypes. Results: We observed a decrease in the diversity of TCR clonotypes in COVID-19 patients compared to healthy controls. However, the overall abundance of dominant clones increased with disease severity. Additionally, we identified significant differences in the genomic rearrangement of variable (V), joining (J), and VJ pairings between the patient groups. Furthermore, the SARS-CoV-2-associated TCRs we identified enabled accurate differentiation between COVID-19 patients and healthy controls (AUC > 0.98) and distinguished those with moderate symptoms from those with more severe forms of the disease (AUC > 0.8). These findings suggest that TCR repertoires can serve as informative biomarkers for monitoring COVID-19 progression. Conclusions: Our study provides valuable insights into TCR repertoire signatures that can be utilized to assess host immunity to COVID-19. These findings have important implications for the use of TCR ß repertoires in monitoring disease development and indicating disease severity.
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COVID-19 , Humanos , SARS-CoV-2 , Linfocitos T , Receptores de Antígenos de Linfocitos T/genética , Gravedad del PacienteRESUMEN
AIM: To elucidate the relationship between macular sensitivity and time in range (TIR) obtained from continuous glucose monitoring (CGM) measures in diabetic patients with or without diabetic retinopathy (DR). METHODS: This was a cross-sectional study including 100 eyes of non-DR patients and 60 eyes of DR patients. An advanced microperimetry was used to quantitate the retinal mean sensitivity (MS) and fixation stability in central macula. TIR of 3.9-10.0 mmol/L was evaluated with CGM. Pearson coefficient analysis and multiple linear regression analysis were used to assess the correlation between TIR and retinal sensitivity. RESULTS: In a comparison of non-DR patients, significant differences (P<0.05) were found in HbA1c, TIR, coefficient of variation (CV), standard deviation of blood glucose (SDBG) and mean amplitude of glucose excursion (MAGE) values in DR patients. Besides, those DR patients had significantly poor best-corrected visual acuity (BCVA, logMAR, P=0.001). In terms of microperimetry parameters, retinal mean sensitivity (MS) and the percentages of fixation points located within 2° and 4° diameter circles were significantly decreased in the DR group (P<0.001, P<0.001, P=0.02, respectively). The bivariate contour ellipse area (BCEA) encompassing 68.2%, 95.4%, 99.6% of fixation points were all significantly increased in the DR group (P=0.01, P=0.006, P=0.01, respectively). Correlation analysis showed that MS were significantly correlated with HbA1c (P=0.01). TIR was positively correlated with MS (r=0.23, P=0.01). SDBG was negatively correlated with MS (r=-0.24, P=0.01) but there was no correlation between CV and MAGE with MS (P>0.05). A multivariable linear regression analysis was performed to prove that TIR and SDBG were both independent risk factors for MS reduction in the DR group. CONCLUSION: TIR is correlated with retinal MS reduction in DR patients, suggesting a useful option for evaluating DR progression.
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Ochratoxin A (OTA), a typical mycotoxin contaminant found in various agricultural products and foods, poses a serious threat to human health. In this study, an aptasensor based on a novel fluorescence probe comprising a G-rich DNA sequence (G43) and thioflavin T (ThT) was designed via hybridization chain reaction (HCR) for the ultrasensitive detection of OTA. G43 is a concatemer of G-quadruplex and G-triplex (a G-quadruplex-like structure with one G-quartet removed), which can drastically enhance the fluorescence intensity of ThT. For this strategy to work, the OTA aptamer is pro-locked in a hairpin structure, denoted "hairpin-locked aptamer" (HL-Apt). OTA binds to HL-Apt, opens the hairpin structure, releases the trigger sequence, and initiates the HCR reaction to form a long DNA duplex and numerous side chains. The side chains combine entirely with the complementary DNA and liberate the pro-locked G43 DNA, dramatically enhancing the intensity of the ThT fluorescence signal. The fluorescence intensity correlates linearly with the OTA concentration between 0.02 and 2.00 ng mL-1, and the method has a detection limit of 0.008 ng mL-1. The developed aptasensor was used to detect OTA in foodstuffs with satisfactory results.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Ocratoxinas , Humanos , Colorantes Fluorescentes/química , Ocratoxinas/análisis , Hibridación de Ácido Nucleico , ADN/genética , ADN/química , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Límite de DetecciónRESUMEN
LAY ABSTRACT: Mealtimes and eating can be difficult for autistic children. A service where different professions work together is required to address the varied and complex mealtime difficulties of autistic children. Little is known about what is needed for such services to be effective. We interviewed six caregivers of autistic children who were engaged in a mealtime service and 10 therapists who are involved in delivering the service to understand their perspectives on the factors that were driving the effectiveness of the mealtime service. We found that different health professionals from different disciplines working together, focusing on adapting intervention to the child and family and managing expectations of the caregiver were important in contributing to outcomes of the mealtime service. The findings of this study can be used to inform the development of more effective interventions and services to support the well-being and development of autistic children.
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Trastorno del Espectro Autista , Trastorno Autístico , Humanos , Niño , Personal de Salud , Cuidadores , Comidas , Conducta AlimentariaRESUMEN
Purpose: We aim to analyze the clinical and genetic features in a Chinese family with congenital retinoschisis by whole-exome sequencing and comprehensive clinical examination. Methods: Six members were recruited from a Chinese family. Three of them were diagnosed as congenital retinoschisis, including two twin siblings. All subjects received a full eye examination. Whole-exome sequencing (WES) and Sanger sequencing were performed on two twin probands and all participants, respectively. Results: A novel splice site mutation RS1.c.53-1G>A was identified in a Chinese congenital retinoschisis family. The mean onset age was 16.7 ± 2.4 years old. The average BCVA in patients was 0.37 ± 0.05. A typical spoke-wheel pattern was observed in all affected eyes. OCT examination results showed fovea schisis and schisis cavities were located in the inner nuclear layer in 100% eyes (6/6). ERG b/a ratio was decreased markedly, but was still more than 1 in the four eyes that were available. Conclusion: The present study discovered a new pathogenic splice cite variant of RS1 in congenital retinoschisis, which expands the mutational spectrum. In contrast to previous research, the phenotype of patients with the same mutation within one family was highly similar. Early molecular testing is crucial for early diagnosis, clinical management, and genetic counseling of patients with congenital retinoschisis.
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Recently, researchers have paid progressively more attention to the study of neural development in infant rats. However, due to the lack of complete intracerebral localization information, such as clear nuclear cluster boundaries, identified main brain structures, and reliable stereotaxic coordinates, it is difficult and restricted to apply technical neuroscience to infant rat's brain. The present study was undertaken to refine the atlas of infant rats. As such, we established a stereotaxic atlas of the infant rat's brain at postnatal days 7-13. Furthermore, dye calibration surgery was performed in P7-P13 infant rats by injecting Methylene blue, and sections were incubated in Nissl solutions. From the panoramic images of the brain sections, atlases were made. Our article has provided the appearance and measurements of P7-P13 Sprague-Dawley rat pups. Whereas the atlas contains a series of about 530 coronal brain section images from olfactory bulbs to the brainstem, a list of abbreviations of the main brain structures, and reliable stereotaxic coordinates, which were demonstrated by vertical and oblique injections with fluorescent dye DiI. The present findings demonstrated that our study of P7-P13 atlases has reasonable nucleus boundaries and accurate and good repeatability of stereotaxic coordinates, which can make up for the shortage of postnatal rat brain atlas currently in the field.
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A new Aspergillus niger whole-cell catalyst was cultured for the cascade hydrolysis of hesperidin (HES) to produce high-value hesperetin-7-O-glucoside (HG) and hesperetin with high conversion (above 90%). Moreover, the inducers used were shown to be useful for cell growth and to induce cells to produce specific enzymes. Remarkably, the type of inducers determined whether the cells can hydrolyze HES. The product composition was also controllable by adjusting different inducers. Transcriptome analysis suggested that both naringin-vs-blank group and saccharose-vs-blank group had obviously difference in gene expression. The naringin-vs-blank group was mainly up-regulated differentially expressed genes (DEGs), while saccharose-vs-blank group was mainly down-regulated DEGs. The Gene Ontology (GO) analysis showed that whether naringin or saccharose was added as an inducer would greatly affect the catalytic activity of cells. Furthermore, 3 genes related to rhamnosidase, 14 genes related to glucosidase and 5 genes related to hydrolase activity were found. These genes were not only involved in rhamnosidase and glucosidase activities, but also spliceosome and the sucrose and starch metabolic pathways. The quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the results of transcriptome sequencing were reliable. This study gave a new approach to hydrolyze HES, and new perspectives to understand the mechanisms associated with the hydrolysis of whole-cell catalyst.
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Citrus , Aspergillus , Aspergillus niger/genética , Flavonoides , Glucosidasas , Hidrólisis , Sacarosa , TranscriptomaRESUMEN
In our previous studies, two polysaccharides (MC-1 and MC-2) were identified in the roots of maca (Lepidium meyenii). In this study, the effects of these two polysaccharides on intestinal immunity and inflammation were assessed using intestinal epithelial cells, i.e., Caco-2 cells. The levels of cytokines and tight junction proteins were measured using ELISA and qPCR, respectively. The results showed that MC-1 and MC-2 were difficult to be absorbed in the Caco-2 cell monolayer, but promoted the secretion of IL-8, IL-10, IL-12, and INF-γ in the Caco-2 cells, and the secretion of TNF-α, IL-6, and NO in macrophages (RAW264.7 cells) via the Caco-2 cell monolayer. Additionally, both polysaccharides inhibited damage induced by lipopolysaccharides to the densification of the Caco-2 monolayer membrane by regulating the expressions of TLR4, ZO-1, and occludin. Furthermore, the secretion of inflammatory factors such as TNF-α, IL-8, and INF-γ was inhibited, and the secretion of the anti-inflammatory factor, IL-10, increased. The results indicated that MC-1 and MC-2 can activate intestinal immunity and alleviate intestinal inflammation in vitro.
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Lepidium , Animales , Células CACO-2 , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mucosa Intestinal/metabolismo , Ratones , Polisacáridos/metabolismo , Polisacáridos/farmacología , Células RAW 264.7RESUMEN
Baicalin, a phenolic glycoside with good lipid-lowering activity, has poor intestinal absorption due to low lipophilicity. In this study, six ester derivatives of baicalin, named BECn (n = 2, 3, 4, 6, 8, and 10) based on their fatty chain lengths, were synthesized by whole-cell catalyzed esterification to improve lipophilicity, and the intestinal absorption and lipid-lowering activity of the synthesized esters were investigated using cell models in vitro. BEC2, BEC3, and BEC4 exhibited higher Papp values than baicalin in Caco-2 cell monolayers. The lipid-lowering activity of the three esters was stronger than baicalin in the cell models of hepatic steatosis, adipocytes and foam macrophages, and was attributed to their higher intracellular accumulation and stronger direct activation of the carnitine palmitoyltransferase 1A. Moreover, these esters were easily hydrolyzed by carboxylesterase and were unstable at pH 7.4, which significantly weakened their absorption and lipid-lowering activity. This study laid the foundation for industrial production and practical application of BAI esters.
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Ésteres , Lípidos , Células CACO-2 , Catálisis , Esterificación , Ésteres/farmacología , Flavonoides , HumanosRESUMEN
In this paper, an enzymatic route for synthesizing phenolic glycoside azelaic acid esters was successfully set up via lipase-catalyzed esterification and transesterification. Among the lipases tested, Candida antarctica lipase B (Novozyme 435) showed the highest activity in catalyzing esterification and Thermomyces lanuginosus (Lipozyme TLIM) gave the highest substrate conversion in catalyzing transesterification for the synthesis of ester. The addition of 4A molecular sieves into the reaction system is found to be an effective method for in situ absorption of the byproduct water and methanol, with which the substrate conversions of the enzymatic esterification and transesterification were 98.7 and 95.1%, respectively. Also, the main product ratios in transesterification were above 99.0% with lipozyme TLIM as a catalyst because the hydrolysis reaction was hindered. The results of the physical and biological properties indicate that all esters had higher Clogâ¯p values than their parent compounds. Also, the esters showed higher intracellular tyrosinase inhibitory and depigmentating activities than phenolic glycosides, azelaic acid (AA), and their physical mixtures due to their higher membrane penetration and tyrosinase inhibitory effects. In particular, piceid 6â³-O-azelaic acid ester (PIA) showed the strongest inhibitory effect against melanin production. Its inhibitory rate was 77.4% at a concentration of 0.25 mM, about 4.2 times higher than that of arbutin (18.5%).
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Ésteres , Glicósidos , Basidiomycota , Ácidos Dicarboxílicos , Esterificación , EurotialesRESUMEN
Esculin is a polyphenol with multiple bioactivities and poor lipophilicity. Therefore, a whole-cell catalytic strategy for esculin acylation was developed to improve its lipophilicity. A total of 12 strains were tested, among which Pseudomonas stutzeri exhibited the highest catalytic activity and mono-acylated regioselectivity. The conversion reached the highest level of 92.7 % at 24 h under the optimal conditions, when vinyl acetate was used as an acyl donor. The catalytic ability of P. stutzeri remained above 60 % after three cycles. Subsequently, five esculin esters with different lengths of fatty chains were synthesized and structurally identified. Of them, esculin-6'-O-octanoate, esculin-6'-O-laurate, and esculin-6'-O-myristate exhibited cytotoxicity on LO2 cells by inducing apoptosis and necrosis. The cytotoxicity of these three esters may attribute to their membrane-disrupting properties. This study provides a novel whole-cell biocatalytic strategy for the acylation of esculin and insight for application of esculin esters as a food additive or drug.
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Esculina , Ésteres , Acilación , Biocatálisis , Lipasa/metabolismoRESUMEN
To explore the potential application of proteases from soybean seedlings in the debittering of soybean protein hydrolysates, soybean seeds were germinated from 1 to 10 days. It was found that the sixth day seedlings exhibited highest proteases activity (130 U/g). After partial purification, the activity of proteases (PSP) from the sixth day seedlings further increased to 2675 U/g. In addition, PSP exhibited maximum activity at 50 â and pH 5.5, and mainly comprised of two proteins with the molecular weight of 64.57 and 25.12 kDa respectively. PSP could decrease the bitterness score of the soybean protein isolate hydrolysate (SPIH) produced by Alcalase 2.4L from 3.45 to 0 in 3 h. Meanwhile, the degree of hydrolysis of SPIH slightly increased from 11.87% to 15.61% without reducing the antioxidant activity. This study may provide a solution to the contradiction between removing the bitterness of soybean protein hydrolysates and maintaining the bioactivity.