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BACKGROUND: Dendrobium officinale flowers (DOF) have the effects of antiaging and nourishing yin, but it lacks pharmacological research on skin aging. OBJECTIVE: Confirming the role of DOF in delaying skin aging based on the "in vitro animal-human" model. METHODS: In this experiment, three kinds of free radical scavenging experiments in vitro, D-galactose-induced aging mouse model, and human antiaging efficacy test were used to test whether DOF can improve skin aging through anti-oxidation. RESULTS: In vitro experiment shows that DOF has certain scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, hydroxyl free radical, and superoxide free radical, and its IC50 is 0.2090 µg/mL, 15.020, and 1.217 mg/mL respectively. DOF can enhance the activities of T-AOC, SOD, CAT, and GSH Px in the serum of aging mice, increase the content of GSH, and reduce the content of MDA when administered with DOF of 1.0, 2.0, and 4.0 g/kg for 6 weeks. In addition, it can enhance the activity of SOD in the skin of aging mice, increase the content of Hyp, and decrease the content of MDA, activated Keap1/Nrf2 pathway in the skin of aging mice. Applying DOF with a concentration of 0.2 g/mL on the face for 8 weeks can significantly improve the skin water score and elasticity value, reduce facial wrinkles, pores, acne, and UV spots, and improve the facial brown spots and roughness. CONCLUSION: DOF can significantly improve skin aging caused by oxidative stress, and its mechanism may be related to scavenging free radicals in the body and improving skin quality.
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Dendrobium , Flores , Estrés Oxidativo , Extractos Vegetales , Envejecimiento de la Piel , Piel , Envejecimiento de la Piel/efectos de los fármacos , Animales , Dendrobium/química , Flores/química , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Ratones , Humanos , Piel/efectos de los fármacos , Piel/metabolismo , Antioxidantes/farmacología , Antioxidantes/administración & dosificación , Masculino , FemeninoRESUMEN
Smart nanorobots have emerged as novel drug delivery platforms in nanomedicine, potentially improving anti-cancer efficacy and reducing side effects. In this study, an intelligent tumor microenvironment-responsive nanorobot is developed that effectively delivers CpG payloads to Toll-like receptor 9 (TLR9)-positive tumors to induce autophagy-mediated cell death for immunotherapy. The nanorobots are fabricated by co-self-assembly of two amphiphilic triblock polymer peptides: one containing the matrix metallopeptidase 2 (MMP2)-cleaved GPLGVRGS motif to control the mechanical opening of the nanorobots and provide targeting capability for TLR-9-positive tumors and the other consisting of an arginine-rich GRRRDRGRS sequence that can condense nuclear acid payloads through electrostatic interactions. Using multiple tumor-bearing mouse models, it is investigated whether the intravenous injection of CpG-loaded nanorobots could effectively deliver CpG payloads to TLR-9-positive tumors and elicit anti-tumor immunity through TLR9 signaling and autophagy. Therefore, besides being a commonly used adjuvant for tumor vaccination, CpG-loaded nanorobots can effectively reprogram the tumor immunosuppressive microenvironment and suppress tumor growth and recurrence. This nanorobot-based CpG immunotherapy can be considered a feasible approach to induce anti-tumor immunity, showing great therapeutic potential for the future treatment of TLR9-positive cancers.
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Functional oligosaccharides exert obesity-reducing effects by acting at various pathological sites responsible for the development of obesity. In this study, tamarind xyloglucan oligosaccharides (TXOS) were used to attenuate metabolic disorders via the gut-liver axis in mice with high-fat-diet (HFD)-induced obesity, as determined through LC/MS-MS and 16S rRNA sequencing technology. A TXOS dose equivalent to 0.39 g/kg/day in humans restored the gut microbiota in obese mice, which was in part supported by the key microflora, particularly Bifidobacterium pseudolongum. Moreover, TXOS reduced the abundance of opportunistic pathogen species, such as Klebsiella variicola and Romboutsia ilealis. The bodyweight and weight gain of TXOS-treated (4.8 g/kg per day) mice began to decrease at the 14th week, decreasing by 12.8% and 23.3%, respectively. Sixteen fatty acids were identified as potential biomarkers in the liver, and B. pseudolongum and caprylic acid were found to tightly regulate each other. This was associated with reduced inflammation in the liver, circulation, and adipose tissue and protection from metabolic disorders. The findings of this study indicate that TXOS can significantly increase the gut microbiota diversity of obese mice and restore the HFD-induced dysbiosis of gut microbiota.
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Owing to the breakthroughs in the prevention and control of the COVID-19 pandemic, messenger RNA (mRNA)-based vaccines have emerged as promising alternatives to conventional vaccine approaches for infectious disease prevention and anticancer treatments. Advantages of mRNA vaccines include flexibility in designing and manipulating antigens of interest, scalability in rapid response to new variants, ability to induce both humoral and cell-mediated immune responses, and ease of industrialization. This review article presents the latest advances and innovations in mRNA-based vaccines and their clinical translations in the prevention and treatment of infectious diseases or cancers. We also highlight various nanoparticle delivery platforms that contribute to their success in clinical translation. Current challenges related to mRNA immunogenicity, stability, and in vivo delivery and the strategies for addressing them are also discussed. Finally, we provide our perspectives on future considerations and opportunities for applying mRNA vaccines to fight against major infectious diseases and cancers. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Therapeutic Approaches and Drug Discovery > Nanomedicine for Infectious Disease Biology-Inspired Nanomaterials > Lipid-Based Structures.
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Enfermedades Transmisibles , Neoplasias , Vacunas , Humanos , Pandemias , ARN Mensajero , Vacunas de ARNm , Neoplasias/prevención & controlRESUMEN
Lead halide perovskites have been explored as a new kind of promising X-ray with wide applications in radiation-associated fields, but low light yield and serious toxicity extremely restrict further applications. To address these issues, we herein demonstrated one new zero-dimensional (0D) organic-inorganic hybrid cuprous halide of [BAPMA]Cu2Br5 (BAPMA = N,N-Bis(3-aminopropyl) methylamine) containing discrete [Cu4Br10]6- tetramers as excellent lead-free scintillators. Upon UV light excitation, [BAPMA]Cu2Br5 displays highly efficient broadband yellowish-green light emission with one dominant peak at 526 nm, a large Stokes shift of 244 nm, and a high photoluminescent quantum yield of 53.40%. Significantly, this broadband light emission can also be excited by higher-energy X-ray as radioluminescence with a high scintillation light yield of 43,744 photons/MeV. The detection limit of 0.074 µGyair/s is also far less than the required value for regular medical diagnostics of 5.5 µGyair/s. The solution-assembled hybrid structure facilely enables the [BAPMA]Cu2Br5-based scintillation screen to display high-performance X-ray imaging with a spatial resolution of 15.79 lp/mm showcasing potential application in X-ray radiography. In brief, combined merits of low toxicity and cost, negligible self-absorption, a low detection limit, considerable light yield, and spatial resolution highlight the excellent scintillation performance of 0D hybrid cuprous halide.
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Dihydroartemisinin (DHA), an active antimalaria metabolite derived from artemisinin, has received increasing attention for its anticancer activities. However, little is known about the anticancer mechanisms of DHA, although the existing data define its antimalaria effects by producing excessive reactive oxygen species (ROS). In this study, we showed that DHA effectively suppresses in vitro and in vivo tumor growth of non-small cell lung cancer (NSCLC) without perceptible toxicity on heart, liver, spleen, lung, and kidney tissues. Of note, DHA inhibited the expression of B7-H3 rather than PD-L1, whereas overexpression of B7-H3 completely rescued DHA's inhibition on cell proliferation and migration of NSCLC A549 and HCC827 cells. B7-H3 overexpression also largely inhibited DHA's induction on the apoptosis of the two cell lines. Furthermore, DHA treatment led to increased infiltration of CD8+ T Lymphocytes in the xenografts as compared with that of negative controls. Taken together, our results suggest that B7-H3 but not PD-L1 is involved in the antitumor effects of DHA in NSCLC, which may be indicative of an effective B7-H3 blockade and further combination with anti-PD-L1/PD-1 immunotherapy.
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Artemisininas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Artemisininas/farmacología , Artemisininas/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , AnimalesRESUMEN
2'-Fucosyllactose (2'-FL) is known for its ability to provide various health benefits to infants, such as gut maturation, pathogen resistance, improved immunity, and nervous system development. However, the production of 2'-FL using α-L-fucosidases is hindered by the lack of low-cost natural fucosyl donors and high-efficiency α-L-fucosidases. In this work, a recombinant xyloglucanase from Rhizomucor miehei (RmXEG12A) was applied to produce xyloglucan-oligosaccharide (XyG-oligos) from apple pomace. Then, an α-L-fucosidase gene (PbFucB) was screened from the genomic DNA of Pedobacter sp. CAU209 and expressed in Escherichia coli. The capability of purified PbFucB to catalyze XyG-oligos and lactose to synthesize 2'-FL was further evaluated. The deduced amino acid sequence of PbFucB shared the highest identity (38.4%) with that of other reported α-L-fucosidases. PbFucB showed the highest activity at pH 5.5 and 35 °C. It catalyzed the hydrolysis of 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc, 20.3 U mg-1), 2'-FL (8.06 U mg-1), and XyG-oligos (0.43 U mg-1). Furthermore, PbFucB demonstrated a high enzymatic conversion rate in 2'-FL synthesis with pNP-Fuc or apple pomace-derived XyG-oligos as donors and lactose as acceptor. Under the optimized conditions, PbFucB converted 50% of pNP-Fuc or 31% of the L-fucosyl residue in XyG-oligos into 2'-FL. This work elucidated an α-L-fucosidase that mediates the fucosylation of lactose and provided an efficient enzymatic strategy to synthesize 2'-FL either from artificial pNP-Fuc or natural apple pomace-derived XyG-oligos. KEY POINTS: ⢠Xyloglucan-oligosaccharide (XyG-oligos) was produced from apple pomace by a xyloglucanase from Rhizomucor miehei. ⢠An α-L-fucosidase (PbFucB) from Pedobacter sp. CAU209 shared the highest identity (38.4%) with reported α-L-fucosidases. â¢PbFucB synthesized 2'-FL using apple pomace-derived XyG-oligos and lactose with a conversion ratio of 31%.
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Malus , Pedobacter , Lactante , Humanos , alfa-L-Fucosidasa/genética , alfa-L-Fucosidasa/metabolismo , Malus/metabolismo , Lactosa/metabolismo , Oligosacáridos/metabolismoRESUMEN
Two-dimensional hybrid lead perovskites have attracted a great deal of attention in white-light-emitting diodes, but the serious toxicity of Pb2+ and the limited photoluminescence quantum yield (PLQY) still restrict further optoelectronic application. To address these issues, a new combining photon strategy was proposed to achieve highly efficient broadband white-light emission in a new family of zero-dimensional (0D) indium halides based on an [InCl6]3- octahedron. Remarkably, these 0D halides display dual-band white-light emission derived from the synergistic work of blue- and yellow-light-emitting bands, which can be ascribed to the radiative recombination of bound excitons in organic cations and self-trapped excitons in inorganic anions, respectively, based on spectroscopy and theoretical studies. In-depth first-principles calculation demonstrates that the increased structural deformability effectively improves the PLQY from 7.01% to 18.56%. As a proof of concept, this work provides a profound understanding for advancing the rational design of novel single-component 0D lead-free halides as high-performance white-light emitters.
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Partially hydrolyzed konjac powder (PHKP) can be used to increase the daily intake of dietary fibers of consumers. To produce PHKP by enzymatic hydrolysis, a novel ß-mannanase gene (McMan5B) from Malbranchea cinnamomea was expressed in Pichia pastoris. It showed a low identity of less than 52% with other GH family 5 ß-mannanases. Through high cell density fermentation, the highest ß-mannanase activity of 42200 U mL-1 was obtained. McMan5B showed the maximal activity at pH 7.5 and 75 °C, respectively. It exhibited excellent pH stability and thermostability. Due to the different residues (Phe214, Pro253, and His328) in catalytic groove and the change of ß2-α2 loop, McMan5B showed unique hydrolysis property as compared to other ß-mannanases. The enzyme was employed to hydrolyze konjac powder for controllable production of PHKP with a weight-average molecular weight of 22000 Da (average degree of polymerization 136). Furthermore, the influence of PHKP (1.0%-4.0%) on the qualities of steamed bread was evaluated. The steamed bread adding 3.0% PHKP had the maximum specific volume and the minimum hardness, which showed 11.0% increment and 25.4% decrement as compared to the control, respectively. Thus, a suitable ß-mannanase for PHKP controllable production and a fiber supplement for steamed bread preparation were provided in this study. KEY POINTS: ⢠A novel ß-mannanase gene (McMan5B) was cloned from Malbranchea cinnamomea and expressed in Pichia pastoris at high level. ⢠McMan5B hydrolyzed konjac powder to yield partially hydrolyzed konjac powder (PHKP) instead of manno-oligosaccharides. ⢠PHKP showed more positive effect on the quality of steamed bread than many other dietary fibers including konjac powder.
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Amorphophallus , beta-Manosidasa , Amorphophallus/genética , Clonación Molecular , Concentración de Iones de Hidrógeno , Mananos/química , Onygenales , Pichia/genética , Polvos , beta-Manosidasa/química , beta-Manosidasa/genéticaRESUMEN
Endometrial cancer is one of the three most common malignant tumors in the female reproductive system. Advanced and recurrent endometrial cancers have poor prognoses and lack effective treatments. Poly (ADP-ribose) polymerase (PARP) inhibitors have been applied to many different types of tumors, and they can selectively kill tumor cells that are defective in homologous recombination repair. Endometrial cancer is characterized by mutations in homologous recombination repair genes; accordingly, PARP inhibitors have achieved positive results in off-label treatments of endometrial cancer cases. Clinical trials of PARP inhibitors as monotherapies and within combination therapies for endometrial cancer are ongoing. For this review, we searched PubMed with "endometrial cancer" and "PARP inhibitor" as keywords, and we used "olaparib", "rucaparib", "niraparib" and "talazoparib" as search terms in clinicaltrials.gov for ongoing trials. The literature search ended in October 2020, and only English-language publications were selected. Multiple studies confirm that PARP inhibitors play an important role in killing tumor cells with defects in homologous recombination repair. Its combination with immune checkpoint inhibitors, PI3K/AKT/mTOR pathway inhibitors, cell cycle checkpoint inhibitors, and other drugs can improve the treatment of endometrial cancer.
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Antineoplásicos , Neoplasias Endometriales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/genética , Femenino , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Poli(ADP-Ribosa) Polimerasas/metabolismoRESUMEN
Phylogenetic relationships of the subgenus Oxyphortica were reconstructed based on two mitochondrial genes (COI and ND2). The results revealed the paraphyly of Oxyphortica and supported high levels of cryptic diversity within this subgenus. By integrating morphological characteristics and molecular evidence, we identified 17 new species as members of Oxyphortica: S. (O.) amphigya sp. nov., S. (O.) armillata sp. nov., S. (O.) ashima sp. nov., S. (O.) bawo sp. nov., S. (O.) crypta sp. nov., S. (O.) gelea sp. nov., S. (O.) hengduanmontana sp. nov., S. (O.) jinmingi sp. nov., S. (O.) mengbalanaxi sp. nov., S. (O.) mouig sp. nov., S. (O.) setipes sp. nov., S. (O.) shangrila sp. nov., S. (O.) tsauri sp. nov., S. (O.) valleculata sp. nov., S. (O.) wanhei sp. nov., S. (O.) yangjin sp. nov. and S. (O.) hypophaia sp. nov. To test the early morphological identifications and confirm the species boundaries, different species delimitation methods, including Automatic Barcode Gap Discovery (ABGD) and Bayesian Phylogenetics and Phylogeography (BP&P), were used, together with traditional distance. All species boundaries were clearly defined. As Oxyphortica species are mainly distributed across Southwest China (e.g., 20 spp. from the Hengduan Mountains), the complex climate and topographic landforms of the area may be responsible for the high levels of species diversity and endemism.
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Increasing atmospheric nitrogen (N) deposition greatly affects species diversity, productivity, and stability of ecosystems. It is thus of the great importance to understand how grassland N pools respond to the increased atmospheric N deposition. This study was conducted in a meadow steppe in Erguna, Inner Mongolia, China. There were six levels of N addition (i.e., 0, 2, 5, 10, 20 and 50 g·m-2·a-1) and two levels of mowing (i.e., mowing and unmown). Samples of aboveground tissues of dominant plant, root, aboveground litter, and soil to the depth of 100 cm were collected in the seventh year after treatments. The N content was measured and the N pool was calculated. The results showed that N addition significantly increased the N content of aboveground plant tissues and litter, as well as N pools of Leymus chinensis, plant community, litter and ecosystem. Mowing significantly increased the N content of L. chinensis leaf and litter, but reduced N pools of L. chinensis, plant community and litter, and did not affect their responses to N addition. There was a significant interactive effect between mowing and N addition on plant community N pool. High levels of N addition in the unmown treatment led to more N stored in the litter pool, with the saturation threshold for the plant community N pool occurred at 10 g·m-2·a-1. Under mowing treatment, the plant community N pool increased with the increasing N addition, and more N stored in plant community N pool after mowing. Mowing could alleviate the negative impacts of increasing N deposition on biodiversity and ecosystem stability, and extended postponing the occurrence of ecosystem N saturation induced by increasing N deposition.
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Ecosistema , Nitrógeno , Pradera , Nitrógeno/análisis , Poaceae , SueloRESUMEN
The xyloglucanase gene (RmXEG12A) from Rhizomucor miehei CAU432 was successfully expressed in Pichia pastoris. The highest xyloglucanase activity of 25,700 U mL-1 was secreted using high cell density fermentation. RmXEG12A was optimally active at pH 7.0 and 65 °C, respectively. The xyloglucanase exhibited the highest specific activity towards xyloglucan (7915.5 U mg-1). RmXEG12A was subjected to hydrolyze tamarind powder to produce xyloglucan oligosaccharides with the degree of polymerization (DP) 7-9. The hydrolysis ratio of xyloglucan in tamarind powder was 89.8%. Moreover, xyloglucan oligosaccharides (2.0%, w/w) improved the water holding capacity (WHC) of yoghurt by 1.1-fold and promoted the growth of Lactobacillus bulgaricus and Streptococcus thermophiles by 2.3 and 1.6-fold, respectively. Therefore, a suitable xyloglucanase for tamarind powder hydrolysis was expressed in P. pastoris at high level and xyloglucan oligosaccharides improved the quality of yoghurt.
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Glucanos/biosíntesis , Glicósido Hidrolasas/metabolismo , Oligosacáridos/biosíntesis , Rhizomucor/enzimología , Saccharomycetales/metabolismo , Xilanos/biosíntesis , Yogur , Estabilidad de Enzimas , Glucanos/aislamiento & purificación , Glicósido Hidrolasas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Hidrólisis , Lactobacillus delbrueckii/crecimiento & desarrollo , Peso Molecular , Oligosacáridos/aislamiento & purificación , Streptococcus/crecimiento & desarrollo , Tamarindus/química , Temperatura , Factores de Tiempo , Xilanos/aislamiento & purificaciónRESUMEN
With the widespread occurrence of aquaculture diseases and the broad application of antibiotics, drug-resistant pathogens have increasingly affected aquatic animals' health. Marine probiotics, which live under high pressure in a saltwater environment, show high potential as a substitute for antibiotics in the field of aquatic disease control. In this study, twenty strains of non-hemolytic bacteria were isolated from the intestine of wild oysters and perch, and a model of Caenorhabditis elegans infected by Vibrio anguillarum was established. Based on the model, ML1206, which showed a 99% similarity of 16S rRNA sequence to Planococcus maritimus, was selected as a potential marine probiotic, with strong antibacterial capabilities and great acid and bile salt tolerance, to protect Caenorhabditis elegans from being damaged by Vibrio anguillarum. Combined with plate counting and transmission electron microscopy, it was found that strain ML1206 could significantly inhibit Vibrio anguillarum colonization in the intestinal tract of Caenorhabditis elegans. Acute oral toxicity tests in mice showed that ML1206 was safe and non-toxic. The real-time qPCR results showed a higher expression level of genes related to the antibacterial peptide (ilys-3) and detoxification (ugt-22, cyp-35A3, and cyp-14A3) in the group of Caenorhabditis elegans protected by ML1206 compared to the control group. It is speculated that ML1206, as a potential probiotic, may inhibit the infection caused by Vibrio anguillarum through stimulating Caenorhabditis elegans to secrete antibacterial effectors and detoxification proteins. This paper provides a new direction for screening marine probiotics and an experimental basis to support the potential application of ML1206 as a marine probiotic in aquaculture.
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Caenorhabditis elegans/microbiología , Planococcaceae , Probióticos/administración & dosificación , Vibriosis/prevención & control , Animales , Acuicultura , Femenino , Intestinos/microbiología , Masculino , Ratones , Ratones Endogámicos ICR , Ostreidae/microbiología , Planococcaceae/genética , Planococcaceae/aislamiento & purificación , Probióticos/toxicidad , ARN Ribosómico 16S , Sobrevida , Vibrio/aislamiento & purificaciónRESUMEN
The appearance of the spurious absorption frequencies caused by the frequency conversion process at the broadband THz pulse propagation in a medium is theoretically and experimentally discussed. The spurious absorption frequencies appear due to both the frequency doubling and generation of waves with sum or difference frequency. Such generation might occur because of the nonlinear response of a medium or its non-instantaneous response. This phenomenon is confirmed by the results of a few physical experiments provided with the THz CW signals and broadband THz pulses that are transmitted through the ordinary or dangerous substances. A high correlation between the time-dependent spectral intensities for the basic frequency and generated frequencies is demonstrated while using the computer simulation results. This feature of the frequency conversion might be used for the detection and identification of a substance.
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This investigation was carried out to offer insight into the formation and antioxidant activity of Maillard reaction products (MRPs) derived from various sugar-amino acid model systems active in the roasting of sesame seeds. Reducing sugars (glucose, fructose, and xylose) and amino acids (serine, cystine, arginine, and lysine) present in sesame seeds were used to prepare the MRPs at various reaction times, and then the effect of reaction time on the MRPs derived from the various model systems was investigated. Within the first 15 min, the amounts of free amino groups decreased around 40% remaining amino groups of Lys-sugar model and around 75% remaining amino groups of Arg-sugar model. Results indicated that reducing sugar and free amino groups decreased obviously in Lys- and Arg-model systems. Based on correlation coefficient of antioxidant activities assessment and MRP formation in the Lys- and Arg-model systems above 0.978 and an extremely significant correlation in Pearson test exists, a conclusion could be made that these model systems are critical contributing factors in MRP formation during the roasting of sesame seeds. These findings offer insight into the formation and antioxidation of MRPs during the sesame seeds roasting.
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Aminoácidos , Antioxidantes , Culinaria/métodos , Calor , Reacción de Maillard , Sesamum/química , Azúcares , Agua , Factores de TiempoRESUMEN
A novel Gram-stain-negative, facultatively anaerobic, flagellated and spiral-shaped bacterium, designated WDS2A16AT was isolated from a marine solar saltern in Weihai, PR China. Growth was observed at 20-40 °C (optimal 33-37 °C), 1-15â% (w/v) NaCl (optimal 3-4â%) and pH 6.0-9.0 (optimal pH 7.5). Major cellular fatty acids (>10â%) were C18â:â1ω7c and C16â:â0. Phosphatidylglycerol, diphosphatidylglycerol and an unidentified glycolipid were detected as the predominant polar lipids. The sole respiratory quinone was Q-8. The DNA G+C content of strain WDS2A16AT was 48.5 mol%. The 16S rRNA gene sequence similarities of WDS2A16AT with other species were less than 91â%. The average nucleotide identity, in silico DNA-DNA hybridization and amino acid identity of strain WDS2A16AT with the most related strain Gynuella sunshinyii YC6258 T were 66.1, 19.3 and 48.1â%, respectively. Comparative analysis of 16S rRNA gene sequences and phenotypic characterization indicated that strain WDS2A16AT represents a novel species in a new genus, for which the name Salinibius halmophilus gen. nov., sp. nov. is proposed. The type strain is WDS2A16AT (=KCTC 52225T=MCCC 1H00139T).
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Gammaproteobacteria/clasificación , Filogenia , Salinidad , Microbiología del Agua , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Gammaproteobacteria/aislamiento & purificación , Glucolípidos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/químicaRESUMEN
BACKGROUND: In recent years, cold-pressed oils have become more and more popular with consumers. However, their oxidative stability is low. Improving the oxidative stability of cold-pressed oils will increase their shelf life. Maillard reaction products (MRPs) have been shown to promote the oxidative stability of lipids. In this study, products from the Maillard reaction of reducing sugars and sesame enzymatically hydrolyzed protein (SEHP) were added to cold-pressed sesame oils to improve their oxidative stability. RESULTS: Three types of MRPs from reducing sugars (xylose, fructose, and glucose) and SEHP were prepared. Xylose-SEHP MRPs prepared under optimum conditions had the highest antioxidant activities among the three. The optimum conditions for xylose-SEHP were as follows: reaction temperature, 130 °C; reaction time, 180 min; pH, 6.5; and sugar/protein ratio, 10:1. The addition of xylose-SEHP MRPs at a level of 20 g kg-1 could significantly improve the oxidative stability of cold-pressed sesame oil. Besides, the addition of MRPs reduced the loss of tocopherol. The interaction of MRPs with endogenous antioxidants in the sesame oil (sesamol and tocopherol) was proved by comparison with lard. There was a synergistic increase in antioxidant activity for the combination of MRPs and sesamol and the combination of MRPs and tocopherol. CONCLUSIONS: The results provide evidence that adding certain MRPs can improve the oxidative stability of cold-pressed sesame oil. © 2019 Society of Chemical Industry.
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Manipulación de Alimentos/métodos , Fructosa/química , Glucosa/química , Productos Finales de Glicación Avanzada/química , Proteínas de Plantas/química , Aceite de Sésamo/química , Sesamum/química , Xilosa/química , Aditivos Alimentarios/química , Reacción de Maillard , Oxidación-ReducciónRESUMEN
BACKGROUND: ß-Sitosterol is a plant metabolite with a broad range of anti-fungal activity, however, this compound is not toxic against a few fungal species. The target of ß-sitosterol and the nature of its selective toxicity are not yet clear. Using a yeast model system and taking advantage of molecular biology and computational approaches, we identify the target and explain why ß-sitosterol is not toxic against some fungal pathogens. RESULTS: ß-Sitosterol (200 µg mL-1 ) is toxic against yeast cells expressing only Osh4 (an oxysterol-binding protein) and harbouring a upc2-1 mutation (which enables sterol uptake), but not against yeast strains expressing all seven Osh proteins and harbouring a upc2-1 mutation. Furthermore, ß-sitosterol is not toxic against yeast strains without the upc2-1 mutation irrespective of the number of Osh proteins being expressed. The deletion of COQ1 (a gene known to be highly induced upon deletion of OSH4) enhances the toxicity of ß-sitosterol in yeast cells expressing only Osh4 and harbouring the upc2-1 mutation. Molecular modelling suggests that ß-sitosterol binds to Osh4 and the binding mode is similar to the binding of cholesterol to Osh4. CONCLUSION: Our results indicate that the concentrations of ß-sitosterol, and Osh4, as well as its homologues within cells, are most likely the main determinants of ß-sitosterol toxicity. Furthermore, some fungal species do not take up sterols, e.g. Saccharomyces cerevisiae, under aerobic conditions. Therefore, sterol uptake may also contribute to the ß-sitosterol anti-fungal effect. These findings enable predicting the toxicity of ß-sitosterol against plant fungal pathogens. © 2019 Society of Chemical Industry.
Asunto(s)
Saccharomyces cerevisiae , Oxiesteroles , Proteínas de Saccharomyces cerevisiae , SitoesterolesRESUMEN
A Gram-stain-negative, non-flagellated, catalase-positive, oxidase-positive bacterial strain, designated YLY08T, was isolated from the gut microflora of sea bass (Dicentrarchus labrax L.) collected from the coast of Yuanyao Wharf, Weihai, PR China, and subjected to a polyphasic taxonomic study. Strain YLY08T grew optimally at 28-30 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0â% (w/v) NaCl. Poly-ß-hydroxybutyrate granules were produced. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain YLY08T clustered with the type strain of Oceaniglobus indicus, with which it exhibited 95.3â% sequence similarity, while the similarity to other genera was below 95.0â%. Genomic analyses, including average nucleotide identity and the digital DNA-DNA hybridization, clearly separated YLY08T from O. indicus MCCC 1A11863T with values below the thresholds for species delineation. The major cellular fatty acid was summed feature 8 (C18â:â1ω7c and/or C18â:â1ω6c). The sole respiratory quinone detected was Q-10. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, diphosphatidylglycerol, one unidentified aminolipid and one unidentified phospholipid. The genome of strain YLY08T, with 38 assembled contigs, was 3.9 Mb long with a G+C content of 59.0 mol%. The results of the phenotypical, phylogenetic and biochemical analyses between the strain YLY08T and the related type strain indicated that this strain represents a novel species in genus Oceaniglobus within the family Rhodobacteraceae, for which the name Oceaniglobus ichthyenteri sp. nov. is proposed. The type strain is YLY08T (=MCCC 1H00318T=KCTC 62182T).