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1.
Chem Soc Rev ; 53(14): 7392-7425, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38894661

RESUMEN

Descriptors play a crucial role in electrocatalysis as they can provide valuable insights into the electrochemical performance of energy conversion and storage processes. They allow for the understanding of different catalytic activities and enable the prediction of better catalysts without relying on the time-consuming trial-and-error approaches. Hence, this comprehensive review focuses on highlighting the significant advancements in commonly used descriptors for critical electrocatalytic reactions. First, the fundamental reaction processes and key intermediates involved in several electrocatalytic reactions are summarized. Subsequently, three types of descriptors are classified and introduced based on different reactions and catalysts. These include d-band center descriptors, readily accessible intrinsic property descriptors, and spin-related descriptors, all of which contribute to a profound understanding of catalytic behavior. Furthermore, multi-type descriptors that collectively determine the catalytic performance are also summarized. Finally, we discuss the future of descriptors, envisioning their potential to integrate multiple factors, broaden application scopes, and synergize with artificial intelligence for more efficient catalyst design and discovery.

2.
J Bacteriol ; 206(6): e0027323, 2024 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-38717111

RESUMEN

Type VI secretion system (T6SS) is a potent weapon employed by various Pseudomonas species to compete with neighboring microorganisms for limited nutrients and ecological niches. However, the involvement of T6SS effectors in interbacterial competition within the phytopathogen Pseudomonas syringae remains unknown. In this study, we examined two T6SS clusters in a wild-type P. syringae MB03 and verified the involvement of one cluster, namely, T6SS-1, in interbacterial competition. Additionally, our results showed that two T6SS DNase effectors, specifically Tde1 and Tde4, effectively outcompeted antagonistic bacteria, with Tde4 playing a prominent role. Furthermore, we found several cognate immunity proteins, including Tde1ia, Tde1ib, and Tde4i, which are located in the downstream loci of their corresponding effector protein genes and worked synergistically to protect MB03 cells from self-intoxication. Moreover, expression of either Tde1 or C-terminus of Tde4 in Escherichia coli cells induced DNA degradation and changes in cell morphology. Thus, our results provide new insights into the role of the T6SS effectors of P. syringae in the interbacterial competition in the natural environment. IMPORTANCE: The phytopathogen Pseudomonas syringae employs an active type VI secretion system (T6SS) to outcompete other microorganisms in the natural environment, particularly during the epiphytic growth in the phyllosphere. By examining two T6SS clusters in P. syringae MB03, T6SS-1 is found to be effective in killing Escherichia coli cells. We highlight the excellent antibacterial effect of two T6SS DNase effectors, namely, Tde1 and Tde4. Both of them function as nuclease effectors, leading to DNA degradation and cell filamentation in prey cells, ultimately resulting in cell death. Our findings deepen our understanding of the T6SS effector repertoires used in P. syringae and will facilitate the development of effective antibacterial strategies.


Asunto(s)
Proteínas Bacterianas , Desoxirribonucleasas , Pseudomonas syringae , Sistemas de Secreción Tipo VI , Pseudomonas syringae/genética , Pseudomonas syringae/metabolismo , Pseudomonas syringae/enzimología , Sistemas de Secreción Tipo VI/metabolismo , Sistemas de Secreción Tipo VI/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Desoxirribonucleasas/metabolismo , Desoxirribonucleasas/genética , Regulación Bacteriana de la Expresión Génica , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos
3.
Chemistry ; 30(33): e202400629, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38594211

RESUMEN

Herein, we synthesized two donor-acceptor (D-A) type small organic molecules with self-assembly properties, namely MPA-BT-BA and MPA-2FBT-BA, both containing a low acidity anchoring group, benzoic acid. After systematically investigation, it is found that, with the fluorination, the MPA-2FBT-BA demonstrates a lower highest occupied molecular orbital (HOMO) energy level, higher hole mobility, higher hydrophobicity and stronger interaction with the perovskite layer than that of MPA-BT-BA. As a result, the device based-on MPA-2FBT-BA displays a better crystallization and morphology of perovskite layer with larger grain size and less non-radiative recombination. Consequently, the device using MPA-2FBT-BA as hole transport material achieved the power conversion efficiency (PCE) of 20.32 % and remarkable stability. After being kept in an N2 glove box for 116 days, the unsealed PSCs' device retained 93 % of its initial PCE. Even exposed to air with a relative humidity range of 30±5 % for 43 days, its PCE remained above 91 % of its initial condition. This study highlights the vital importance of the fluorination strategy combined with a low acidity anchoring group in SAMs, offering a pathway to achieve efficient and stable PSCs.

4.
AIDS Behav ; 28(8): 2590-2597, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38884666

RESUMEN

This retrospective study explored the association between travel burden and timely linkage to care (LTC) among people with HIV (PWH) in South Carolina. HIV care data were derived from statewide all-payer electronic health records, and timely LTC was defined as having at least one viral load or CD4 count record within 90 days after HIV diagnosis before the year 2015 and 30 days after 2015. Travel burden was measured by average driving time (in minutes) to any healthcare facility visited within six months before and one month after the initial HIV diagnosis. Multivariable logistic regression models with the least absolute shrinkage and selection operator were employed. From 2005 to 2020, 81.2% (3,547 out of 4,366) of PWH had timely LTC. Persons who had longer driving time (adjusted Odds Ratio (aOR): 0.37, 95% CI: 0.14-0.99), were male versus female (aOR: 0.73, 95% CI: 0.58-0.91), had more comorbidities (aOR: 0.73, 95% CI: 0.57-0.94), and lived in counties with a higher percentage of unemployed labor force (aOR: 0.21, 95% CI: 0.06-0.71) were less likely to have timely LTC. However, compared to those aged between 18 and 24 years old, those aged between 45 and 59 (aOR:1.47, 95% CI: 1.14-1.90) or older than 60 (aOR:1.71, 95% CI: 1.14-2.56) were more likely to have timely LTC. Concentrated and sustained interventions targeting underserved communities and the associated travel burden among newly diagnosed PWH who are younger, male, and have more comorbidities are needed to improve LTC and reduce health disparities.


Asunto(s)
Infecciones por VIH , Viaje , Humanos , Masculino , Femenino , South Carolina/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/diagnóstico , Adulto , Estudios Retrospectivos , Persona de Mediana Edad , Recuento de Linfocito CD4 , Adulto Joven , Carga Viral , Adolescente , Accesibilidad a los Servicios de Salud
5.
PLoS One ; 19(1): e0296693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38215168

RESUMEN

With the rapid development of technologies such as cloud computing and big data, various levels of government departments in the country have successively introduced digital subsidy policies to promote enterprises' digital transformation. However, the effectiveness of these policies and their ability to truly achieve policy objectives have become pressing concerns across society. Against this backdrop, this paper employs a moderated mediation effects model to empirically analyze the incentive effects of financial subsidies on the digital transformation of A-share listed manufacturing companies in the Shanghai and Shenzhen stock markets from 2013 to 2022. The research findings indicate a significant promotion effect of financial subsidies on the digital transformation of manufacturing enterprises, especially demonstrating a notable incentive impact on the digital transformation of large enterprises, non-asset-intensive enterprises, technology-intensive enterprises, and non-labor-intensive enterprises. However, the incentive effect on the digital transformation of small and medium-sized enterprises (SMEs), asset-intensive enterprises, non-technology-intensive enterprises, and labor-intensive enterprises is not significant. Notably, the expansion of financial subsidies positively influences the augmentation of R&D investment within manufacturing enterprises, subsequently providing indirect encouragement for their digital transformation. Additionally, the incorporation of the degree of marketization implies its potential to moderate both the direct and indirect impacts of financial subsidies on enterprise digital transformation. This study enriches the research on the mechanism of the role of financial subsidies in digital transformation and provides empirical evidence on how market participation influences the effects of financial subsidies, thereby assisting policymakers in comprehensively understanding the impact of financial subsidy policies on different types of enterprises.


Asunto(s)
Macrodatos , Nube Computacional , China , Comercio , Investigación Empírica
6.
Environ Mol Mutagen ; 65(1-2): 25-46, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38333939

RESUMEN

Previously, we introduced an alternative adherent A375 cell line for clastogenicity and aneugenicity testing using a high content imaging platform. To further characterize the performance of A375 cells, we investigated the sensitivity and specificity of A375 and TK6 cells by directly comparing micronucleus (MN) induction, cytotoxicity (relative cell counts, viability, and apoptosis), clastogenicity (γH2AX), and aneuploidy markers (pH 3, MPM-2, and polyploidy) using flow cytometric methods. We evaluated 14 compounds across different mechanisms (non-genotoxic apoptosis inducers, clastogens, and aneugens with either tubulin binding or aurora kinase inhibiting phenotypes) at 4-h and 24-h post treatment. Both aneugens and clastogens tested positive for micronucleus induction in both cell lines. Apoptosis continued to be a confounding factor for flow cytometry-based micronuclei assessment in TK6 cells as evidenced by positive responses by the three cytotoxicants. Conversely, A375 cells were not affected by apoptosis-related false positive signals and did not produce a positive response in the in vitro micronucleus assay. Benchmark dose response (BMD) analysis showed that the induction of micronuclei and biomarkers occurred at similar concentrations in both cell lines for clastogens and aneugens. By showing that A375 cells have similar sensitivity to TK6 cells but a greater specificity, these results provide additional support for A375 cells to be used as an alternative adherent cell line for in vitro genetic toxicology assessment.


Asunto(s)
Aneugénicos , Mutágenos , Aneugénicos/toxicidad , Citometría de Flujo , Pruebas de Micronúcleos/métodos , Mutágenos/toxicidad , Biomarcadores/metabolismo , Daño del ADN
7.
Food Res Int ; 190: 114607, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945617

RESUMEN

Salmonella, a prominent foodborne pathogen, has posed enduring challenges to the advancement of food safety and global public health. The escalating concern over antibiotic misuse, resulting in the excessive presence of drug residues in animal-derived food products, necessitates urgent exploration of alternative strategies for Salmonella control. Bacteriophages emerge as promising green biocontrol agents against pathogenic bacteria. This study delineates the identification of two novel virulent Salmonella phages, namely phage vB_SalS_ABTNLsp11241 (referred to as sp11241) and phage 8-19 (referred to as 8-19). Both phages exhibited efficient infectivity against Salmonella enterica serotype Enteritidis (SE). Furthermore, this study evaluated the effectiveness of two phages to control SE in three different foods (whole chicken eggs, raw chicken meat, and lettuce) at different MOIs (1, 100, and 10000) at 4°C. It's worth noting that sp11241 and 8-19 achieved complete elimination of SE on eggs after 3 h and 6 h at MOI = 100, and after 2 h and 5 h at MOI = 10000, respectively. After 12 h of treatment with sp11241, a maximum reduction of 3.17 log10 CFU/mL in SE was achieved on raw chicken meat, and a maximum reduction of 3.00 log10 CFU/mL was achieved on lettuce. Phage 8-19 has the same effect on lettuce as sp11241, but is slightly less effective than sp11241 on chicken meat (a maximum 2.69 log10 CFU/mL reduction). In conclusion, sp11241 and 8-19 exhibit considerable potential for controlling Salmonella contamination in food at a low temperature and represent viable candidates as green antibacterial agents for food applications.


Asunto(s)
Pollos , Huevos , Microbiología de Alimentos , Lactuca , Carne , Fagos de Salmonella , Salmonella enteritidis , Lactuca/microbiología , Animales , Huevos/microbiología , Huevos/virología , Pollos/microbiología , Salmonella enteritidis/virología , Carne/microbiología , Inocuidad de los Alimentos , Contaminación de Alimentos/prevención & control , Virulencia
8.
Heliyon ; 10(9): e29701, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38726204

RESUMEN

In this study, isolate Bacillus velezensis1-3 was selected out for its anti- Listeria potency, from which a novel circular bacteriocin, velezin, was purified out of the fermentate, and then characterized. Facilitated with a broad antibacterial spectrum, velezin has demonstrated decent inhibitive activity against of foodborne pathogen L. monocytogenes ATCC 19115. It exerted the antibacterial activity through damaging the membrane integrity of targeted cell and causing leakage of vital elements, including K+ ion. It was noteworthy that velezin also inhibited the biofilm formation by L. monocytogenes ATCC 19115. At the challenge of velezin, L. monocytogenes ATCC 19115 up-regulated expression of genes associated with membrane, ion transporters, stressing-related proteins as well as the genes responsible for the synthesis of small molecule. Taken together, velezin may have potential to be a candidate as natural additive used in food/feed in the future.

9.
Sci Total Environ ; 926: 171904, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38527548

RESUMEN

The ecotoxic endocrine-disrupting chemical di-(2-ethylhexyl) phthalate (DEHP) is ubiquitous in agricultural soil, posing a serious threat to human health. Here, we report efficient soil-borne DEHP degradation and plant growth promotion by a microbial organic fertilizer GK-PPB prepared by combining a recycled garden waste-kitchen waste compost product with ternary compound microbial agent PPB-MA, composed of Penicillium oxalic MB08F, Pseudomonas simiae MB751, and Bacillus tequilensis MB05B. The combination of MB08F and MB751 provided synergistic phosphorus solubilization, and MB05B enhanced the DEHP degradation capacity of MB08F via bioemulsification. Under optimal conditions (25.70 °C and pH 7.62), PPB-MA achieved a 96.81 % degradation percentage for 1000 mg L-1 DEHP within 5 days. The degradation curve followed first-order kinetics with a half-life of 18.24 to 24.76 h. A complete mineralization pathway was constructed after identifying the degradation intermediates of 2H-labeled DEHP. Evaluation in Caenorhabditis elegans N2 showed that PPB-MA eliminated the ecological toxicity of DEHP. A pakchoi (Brassica chinensis L.) pot experiment demonstrated that GK-PPB promoted phosphorus solubilization and plant growth, reduced soil DEHP residue, and decreased DEHP accumulation in pakchoi, suggesting its potential practical utility in environmentally responsible and safe cultivation of vegetables.


Asunto(s)
Dietilhexil Ftalato , Ácidos Ftálicos , Contaminantes del Suelo , Humanos , Dietilhexil Ftalato/metabolismo , Fosfatos , Suelo , Fósforo , Contaminantes del Suelo/análisis
10.
World J Gastrointest Surg ; 16(3): 731-739, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38577073

RESUMEN

BACKGROUND: Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery. They are venous clusters formed by congestion, expansion, and flexion of the venous plexus in the lower part of the rectum. Mixed hemorrhoids bleed easily and recurrently, and this can result in severe anemia. Hence, they may have a negative effect on the health of the patient and surgical treatment is required. Milligan-Morgan hemorrhoidectomy has been widely used since 1937 for the treatment of grade III and IV hemorrhoids. However, most patients experience different degrees of postoperative pain that may cause anxiety. AIM: To assess the factors influencing pain scores and quality of life (QoL) in patients with mixed hemorrhoids post-surgery. METHODS: The clinical data of patients with mixed hemorrhoids who underwent Milligan-Morgan hemorrhoidectomy were collected retrospectively. The basic characteristics of the enrolled patients with mixed hemorrhoids were recorded, and based on the Goligher clinical grading system, the hemorrhoids were classified as grades III or IV. The endpoint of this study was the disappearance of pain in all patients. Quantitative data were presented as mean ± SD, such as age, pain score, and QoL score. Student's t-test was used to compare the groups. RESULTS: A total of 164 patients were enrolled. The distribution of the visual analog scale pain scores of all patients at 3, 7, 14 and 28 d after surgery showed that post-surgery pain was significantly reduced with the passage of time. Fourteen days after the operation, the pain had completely disappeared in some patients. Twenty-eight days after the surgery, none of the patients experienced any pain. Comparing the World Health Organization Quality of Life - BREF self-reporting questionnaire scores of patients between 14 and 28 d after surgery, we observed that the quality-of-life scores of the patients post-surgery had significantly improved. There were six items that were compared at 14- and 28-d post-surgery. The mean QoL score 28 d after surgery (4.79 ± 0.46) was higher than that at 14 d post-surgery (3.79 ± 0.57). The mean health condition score 28 d after surgery (4.80 ± 0.41) was also higher than that at 14 d post-surgery (4.01 ± 0.62). The mean physical health score 28 d after surgery (32.10 ± 2.96) was significantly higher than that at 14 d post-surgery (23.41 ± 2.85). The mean psychological health score 28 d after surgery (27.22 ± 1.62) was significantly higher than that at 14 d post-surgery (21.37 ± 1.70). The mean social relations score 28 d after surgery (12.21 ± 1.59) was significantly higher than that at 14 d post-surgery (6.32 ± 1.66). The mean surrounding environment score 28 d after surgery (37.13 ± 2.88) was significantly higher than that at 14 d post-surgery (28.42 ± 2.86). The differences in quality-of-life scores at day 14 and day 28 post-surgery were observed to be statistically significant (P < 0.001). CONCLUSION: Milligan-Morgan hemorrhoidectomy can significantly improve the postoperative QoL of patients. Age, sex, and the number of surgical resections were important factors influencing Milligan-Morgan hemorrhoidectomy.

11.
Dalton Trans ; 53(14): 6157-6161, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38488126

RESUMEN

In order to improve the oxidative desulfurization (ODS) performance of MOF materials, an effective way is to convert a microporous MOF into a hierarchical porous MOF (HP-MOF) by utilizing the linker selective retention strategy. Herein, UiO-66 with the introduction of an unstable linker ligand (dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate, dhtz) can selectively remove dhtz ligands to form HP-MOF (HP-UiO-66-dhtz) through heat treatment at high temperature. While maintaining the original structure of UiO-66, HP-UiO-66-dhtz features mesopores and abundant Lewis acid sites, showing excellent ODS performance for diphenylthiophene (DBT).

12.
Nat Commun ; 15(1): 4005, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740786

RESUMEN

The neocortex comprises six cortical layers that play a crucial role in information processing; however, it remains unclear whether laminar processing is consistent across all regions within a single cortex. In this study, we demonstrate diverse laminar response patterns in the primary visual cortex (V1) of three male macaque monkeys when exposed to visual stimuli at different spatial frequencies (SFs). These response patterns can be categorized into two groups. One group exhibit suppressed responses in the output layers for all SFs, while the other type shows amplified responses specifically at high SFs. Further analysis suggests that both magnocellular (M) and parvocellular (P) pathways contribute to the suppressive effect through feedforward mechanisms, whereas amplification is specific to local recurrent mechanisms within the parvocellular pathway. These findings highlight the non-uniform distribution of neural mechanisms involved in laminar processing and emphasize how pathway-specific amplification selectively enhances representations of high-SF information in primate V1.


Asunto(s)
Estimulación Luminosa , Corteza Visual Primaria , Vías Visuales , Animales , Masculino , Corteza Visual Primaria/fisiología , Vías Visuales/fisiología , Percepción Visual/fisiología , Corteza Visual/fisiología , Macaca mulatta
13.
Nat Commun ; 15(1): 3870, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719875

RESUMEN

Micro-thermoelectric coolers are emerging as a promising solution for high-density cooling applications in confined spaces. Unlike thin-film micro-thermoelectric coolers with high cooling flux at the expense of cooling temperature difference due to very short thermoelectric legs, thick-film micro-thermoelectric coolers can achieve better comprehensive cooling performance. However, they still face significant challenges in both material preparation and device integration. Herein, we propose a design strategy which combines Bi2Te3-based thick film prepared by powder direct molding with micro-thermoelectric cooler integrated via phase-change batch transfer. Accurate thickness control and relatively high thermoelectric performance can be achieved for the thick film, and the high-density-integrated thick-film micro-thermoelectric cooler exhibits excellent performance with maximum cooling temperature difference of 40.6 K and maximum cooling flux of 56.5 W·cm-2 at room temperature. The micro-thermoelectric cooler also shows high temperature control accuracy (0.01 K) and reliability (over 30000 cooling cycles). Moreover, the device demonstrates remarkable capacity in power generation with normalized power density up to 214.0 µW · cm-2 · K-2. This study provides a general and scalable route for developing high-performance thick-film micro-thermoelectric cooler, benefiting widespread applications in thermal management of microsystems.

14.
Materials (Basel) ; 17(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38893834

RESUMEN

Phosphates play a crucial role in drug design, but their negative charge and high polarity make the transmembrane transport of phosphate species challenging. This leads to poor bioavailability of phosphate drugs. Combretastatin-A4 phosphate (CA4P) is such an anticancer monoester phosphate compound, but its absorption and clinical applicability are greatly limited. Therefore, developing carrier systems to effectively deliver phosphate drugs like CA4P is essential. Anion receptors have been found to facilitate the transmembrane transport of anions through hydrogen bonding. In this study, we developed a tripodal hexaurea anion receptor (L1) capable of binding anionic CA4P through hydrogen bonding, with a binding constant larger than 104 M-1 in a DMSO/water mixed solvent. L1 demonstrated superior binding ability compared to other common anions, and exhibited negligible cell cytotoxicity, making it a promising candidate for future use as a carrier for drug delivery.

15.
Nat Commun ; 15(1): 516, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225259

RESUMEN

The coding privilege of end-spectral hues (red and blue) in the early visual cortex has been reported in primates. However, the origin of such bias remains unclear. Here, we provide a complete picture of the end-spectral bias in visual system by measuring fMRI signals and spiking activities in macaques. The correlated end-spectral biases between the LGN and V1 suggest a subcortical source for asymmetric coding. Along the ventral pathway from V1 to V4, red bias against green peaked in V1 and then declined, whereas blue bias against yellow showed an increasing trend. The feedforward and recurrent modifications of end-spectral bias were further revealed by dynamic causal modeling analysis. Moreover, we found that the strongest end-spectral bias in V1 was in layer 4C[Formula: see text]. Our results suggest that end-spectral bias already exists in the LGN and is transmitted to V1 mainly through the parvocellular pathway, then embellished by cortical processing.


Asunto(s)
Corteza Visual , Vías Visuales , Animales , Corteza Visual/diagnóstico por imagen , Primates , Macaca , Imagen por Resonancia Magnética/métodos , Cuerpos Geniculados , Estimulación Luminosa/métodos
16.
J Phys Chem Lett ; 14(51): 11684-11690, 2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38109369

RESUMEN

Electrochemical NO-to-NH3 conversion has been attracting more attention in the field of green energy, which, however, imposes restrictions on the catalysts. We therefore design a family of dual atom catalysts (DACs) TM1TM2@g-CN and perform high-throughput screening to position the effective catalysts for electrocatalytic NO-to-NH3 conversion from first-principles computations. We identify that TiCr@g-CN (-0.37 V), TiMo@g-CN (-0.36 V), and MnMo@g-CN (-0.43 V) are promising candidates with low overpotentials. In particular, we find that MoMo@g-CN can spontaneously reduce NO to NH3, which makes it an excellent electrocatalyst for the NO reduction reaction (NORR) to be translated to experiments. In terms of the local geometry feature and local electronic structures, we unravel the origin of the high NORR activity and high selectivity of the DAC MoMo@g-CN.

17.
Braz. arch. biol. technol ; 59: e16150343, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951399

RESUMEN

ABSTRACT The purpose of this research was to enhance the production of vitamin K2 by fermentation optimization and Arachis hypogaea supplementation in Flavobacterium sp. mutant SP-L-01. Optimized culture condition were as follows: 6-days shake-flask culture at 37oC with initial pH value 7.0 ± 0.2, shaking speed in 120 r/min and medium volume of 30 mL with 2% inoculums. After optimization of fermentation medium by response surface methodology (RSM), optimized medium were maltose 23.8 g/l, glucose 9.69 g/l, beef extract 15 g/l, K2HPO4 4.5 g/l,NaCl 3.0 g/l and MgSO4·7H2O 0.3 g/l. Production of vitamin K2 after optimization reached to 10.97 mg/l, which is 79.25% higher than that before optimization (6.12 mg/l). 3 mg/mL of arachis hypogaea was added into the medium at 72 h of shake-flake cultivation, which improved the production of menaquinone-4 (MK4) up to 371% and menaquinone-6 (MK6) up to 149% higher than those of the original medium. D-(+)-catechin, one of the components of arachis hypogaea, was added alone into the medium, which also improved the vitamin K2 synthesis.

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