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1.
Molecules ; 28(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37175360

RESUMO

Carbon sequestration is the primary function of biochar. Hence, it is necessary to design biochar with high carbon (C) retention and low C loss. In this study, three P compounds, including KH2PO4, Ca(H2PO4)2, and NH4H2PO4, were premixed with corn stalk (1:4, w/w), aiming to produce biochars (CSB+K, CSB+Ca, and CSB+N) with high C sequestration and slow release of P at three temperatures (300, 500, and 700 °C). The addition of all P sources obviously increased C retention, with the order of NH4H2PO4 (65.6-83.5%) > Ca(H2PO4)2 (60.4-78.2%) > KH2PO4 (50.1-76.1%), compared with the pristine biochar (47.8-73.6%). The addition of Ca(H2PO4)2 and KH2PO4 led to an increase in aromaticity and graphitization, as evidenced by H/C, FTIR, Raman and XPS analysis, whereas an opposite result occurred on CSB+N. Furthermore, all three phosphates reduced C loss of biochars with H2O2 oxidation, and CSB+Ca showed the best effect. Ca(H2PO4)2 and KH2PO4 pretreated biochars had higher resistance to K2Cr2O7 oxidation and thermal treatment. In contrast, the C loss of NH4H2PO4-added biochar at 500 and 700 °C with K2Cr2O7 oxidation was increased by 54% and 36%, respectively. During the pyrolysis process, Ca(H2PO4)2 was transformed into insoluble Ca2P2O7, leading to the lowest P release rate of CSB+Ca. This study indicates that co-pyrolysis of corn stalk and Ca(H2PO4)2 is optimal for increasing C retention, enhancing C stability and improving slow-release performance of P regardless of pyrolysis temperature.


Assuntos
Fosfatos , Fósforo , Temperatura , Sequestro de Carbono , Pirólise , Peróxido de Hidrogênio , Carvão Vegetal , Carbono
2.
Phytomedicine ; 115: 154836, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37119760

RESUMO

BACKGROUND: Liver is a vital organ responsible for metabolizing and detoxifying both endogenous and exogenous substances in the body. However, it is susceptible to damage from chemical and natural toxins. The high incidence and mortality rates of liver disease and its associated complications impose a significant economic burden and survival pressure on patients and their families. Various liver diseases exist, including cholestasis, viral and non-viral hepatitis, fatty liver disease, drug-induced liver injury, alcoholic liver injury, and severe end-stage liver diseases such as cirrhosis, hepatocellular carcinoma (HCC), and cholangiocellular carcinoma (CCA). Recent research has shown that flavonoids found in Citri Reticulatae Pericarpium (CRP) have the potential to normalize blood glucose, cholesterol levels, and liver lipid levels. Additionally, these flavonoids exhibit anti-inflammatory properties, prevent oxidation and lipid peroxidation, and reduce liver toxicity, thereby preventing liver injury. Given these promising findings, it is essential to explore the potential of active components in CRP for developing new drugs to treat liver diseases. OBJECTIVE: Recent studies have revealed that flavonoids, including hesperidin (HD), hesperetin (HT), naringenin (NIN), nobiletin (NOB), naringin (NRG), tangerine (TN), and erodcyol (ED), are the primary bioactive components in CRP. These flavonoids exhibit various therapeutic effects on liver injury, including anti-oxidative stress, anti-cytotoxicity, anti-inflammatory, anti-fibrosis, and anti-tumor mechanisms. In this review, we have summarized the research progress on the hepatoprotective effects of HD, HT, NIN, NOB, NRG, TN, ED and limonene (LIM), highlighting their underlying molecular mechanisms. Despite their promising effects, the current clinical application of these active ingredients in CRP has some limitations. Therefore, further studies are needed to explore the full potential of these flavonoids and develop new therapeutic strategies for liver diseases. METHODS: For this review, we conducted a systematic search of three databases (ScienceNet, PubMed, and Science Direct) up to July 2022, using the search terms "CRP active ingredient," "liver injury," and "flavonoids." The search data followed the PRISMA standard. RESULTS: Our findings indicate that flavonoids found in CRP can effectively reduce drug-induced liver injury, alcoholic liver injury, and non-alcoholic liver injury. These therapeutic effects are mainly attributed to the ability of flavonoids to improve liver resistance to oxidative stress and inflammation while normalizing cholesterol and liver lipid levels by exhibiting anti-free radical and anti-lipid peroxidation properties. CONCLUSION: Our review provides new insights into the potential of active components in CRP for preventing and treating liver injury by regulating various molecular targets within different cell signaling pathways. This information can aid in the development of novel therapeutic strategies for liver disease.


Assuntos
Carcinoma Hepatocelular , Citrus , Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Flavonoides/química , Citrus/química , Anti-Inflamatórios
3.
Arch Microbiol ; 204(8): 512, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864423

RESUMO

Mandarin peel is a by-product from mandarin canning industry containing multiple functional substances with useful properties such as antibacterial and antioxidant activities. To evaluate the effect of bioprocessing, fresh mandarin peels were fermented by Rhizopus stolonifer JP13 for 4 days and then the peels' antioxidant and antimicrobial activities were tested. The flavonoiuds, hesperidin and VC contents in dry peels were also determined. The data showed that the fermented mandarin peels had promoted antibacterial activity against Escherichia coli, Staphylococcus aureus, Aspergillus flavus, and Candida albicans. An increased scavenging effect on free radicals, with 73.0% of·OH scavenging activities were obtained when compared with fresh mandarin peels. We also observed a significant increase on content of flavonoid (334%) and hesperindin (253.7%), a reduced scavenging effect on O2- free radicals (13.94%), and a decrease content of VC (13.7%). The presaging of mandarin peels by Rhizopus stolonifer JP13 strain will promote the functional activities of mandarin peels and accelerate the process of manufacture Citri Reticulatae Pericarpium.


Assuntos
Antioxidantes , Citrus , Antibacterianos , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Rhizopus
4.
Nutr Cancer ; 74(9): 3312-3321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35633093

RESUMO

AIMS: To explore compliance with oral nutritional supplementation (ONS) and to identify the risk factors for noncompliance among gastric cancer patients based on the health belief model (HBM). METHODS: This prospective, observational study included gastric cancer patients at nutritional risk who were prescribed ONS from July to September 2020. Demographic factors, clinical factors, ONS-related factors, social factors and variables derived from the HBM were collected. The outcome of interest was compliance with ONS, which was measured by self-reported intake of ONS. Uni- and multivariate analyses of potential risk factors for noncompliance were performed. RESULTS: A total of 162 gastric cancer patients in the preoperative and adjuvant chemotherapy periods were analyzed. The compliance rate with ONS was 24.7%. Univariate analysis identified thirteen variables as risk factors for decreased compliance. Multivariate logistic analysis indicated that ONS compliance was independently associated with the treatment period, perceived barriers to ONS, the motivation to take ONS, and the timing of taking ONS. CONCLUSION: This study showed that overall ONS compliance among gastric cancer patients was notably low. Patients in the chemotherapy treatment period who took ONS at random times each day perceived more barriers to taking ONS and had a lower level of motivation were associated with lower compliance with ONS.


Assuntos
Desnutrição , Neoplasias Gástricas , Estudos Transversais , Suplementos Nutricionais , Humanos , Estado Nutricional , Estudos Prospectivos , Neoplasias Gástricas/tratamento farmacológico
5.
Mol Oral Microbiol ; 36(5): 278-290, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34351080

RESUMO

Zinc (Zn2+ ) is an essential divalent trace metal for living cells. Intracellular zinc homeostasis is critical to the survival and virulence of bacteria. Thus, the frequent fluctuations of salivary zinc, caused by the low physiological level and the frequent exogenous zinc introduction, present a serious challenge for bacteria colonizing the oral cavity. However, the regulation strategies to keep intracellular Zn2+ homeostasis in Streptococcus mutans, an important causative pathogen of dental caries, are unknown. Because zinc uptake is primarily mediated by an ATP-binding ABC transporter AdcABC in Streptococcus strains, we examined the function of AdcABC and transcription factor AdcR in S. mutans in this study. The results demonstrated that deletion of either adcA or adcCB gene impaired the growth but enhanced the extracellular polymeric matrix production in S. mutans, both of which could be relieved after excessive Zn2+ supplementation. Using RNA sequencing analysis, quantitative reverse transcription polymerase chain reaction examination, LacZ-reporter studies, and electrophoretic mobility shift assay, we showed that a MarR (multiple antibiotic resistance regulator) family transcription factor, AdcR, negatively regulates the expression of the genes adcR, adcC, adcB, and adcA by acting on the adcRCB and adcA promoters in response to Zn2+ concentration in their environmental niches. The deletion of adcR increases the sensitivity of S. mutans to excessive Zn2+ supply. Taken together, our findings suggest that Adc regulon, which consists of a Zn2+ uptake transporter AdcCBA and a Zn2+ -responsive repressor AdcR, plays a prominent role in the maintenance of intracellular zinc homeostasis of S. mutans.


Assuntos
Cárie Dentária , Regulon , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Homeostase , Humanos , Regulon/genética , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Zinco/metabolismo
6.
mSystems ; 6(4): e0078821, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34427509

RESUMO

The ability of Streptococcus mutans to survive and cause dental caries is dependent on its ability to metabolize various carbohydrates, accompanied by extracellular polysaccharide synthesis and biofilm formation. Here, the role of an rel competence-related regulator (RcrR) in the regulation of multiple sugar transportation and biofilm formation is reported. The deletion of the rcrR gene in S. mutans caused delayed growth, decreased biofilm formation ability, and affected the expression level of its multiple sugar transportation-related genes. Transcriptional profiling revealed 17 differentially expressed genes in the rcrR mutant. Five were downregulated and clustered with the sugar phosphotransferase (PTS) systems (mannitol- and trehalose-specific PTS systems). The conserved sites bound by the rcrR promoter were then determined by electrophoretic mobility shift assays (EMSAs) and DNase I footprinting assays. Furthermore, a potential binding motif in the promoters of the two PTS operons was predicted using MEME Suite 5.1.1. RcrR could bind to the promoter regions of the two operons in vitro, and the sugar transporter-related genes of the two operons were upregulated in an rcrR-overexpressing strain. In addition, when RcrR-binding sites were deleted, the growth rates and final yield of S. mutans were significantly decreased in tryptone-vitamin (TV) medium supplemented with different sugars, but not in absolute TV medium. These results revealed that RcrR acted as a transcription activator to regulate the two PTS systems, accompanied by multiple sugar transportation and biofilm formation. Collectively, these results indicate that RcrR is a critical transcription factor in S. mutans that regulates bacterial growth, biofilm formation, and multiple sugar transportation. IMPORTANCE The human oral cavity is a constantly changing environment. Tooth decay is a commonly prevalent chronic disease mainly caused by the cariogenic bacterium Streptococcus mutans. S. mutans is an oral pathogen that metabolizes various carbohydrates into extracellular polysaccharides (EPSs), biofilm, and tooth-destroying lactic acid. The host diet strongly influences the availability of multiple carbohydrates. Here, we showed that the RcrR transcription regulator plays a significant role in the regulation of biofilm formation and multiple sugar transportation. Further systematic evaluation of how RcrR regulates the transportation of various sugars and biofilm formation was also conducted. Notably, this study decrypts the physiological functions of RcrR as a potential target for the better prevention of dental caries.

7.
Zhongguo Zhong Yao Za Zhi ; 46(4): 907-914, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645096

RESUMO

The study is aiming at investigating the application of entropy weight TOPSIS method in the comparison of the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) of Chrysanthemum indicum. The DPPH, ABTS, salicylic acid and spectrophotometry were used to determine the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) of Ch. indicum from 31 different areas in vitro. Take the half inhibition rate of as the evaluation index, two principal components were extracted by the principal component analysis, and their cumulative contribution rate reached at 92.4%. The different areas of Ch. indicum could be divided into Dabei Mountain and Qinling-Taihang Mountain by use principal component to analysis. The entropy weight TOPSIS method was used to objectively assign weights to five indexes, calculate the weight of each index and set up the best and worst scheme of the evaluation object, and the relative proximity(C_i) was used as the measure to construct the multi-index comprehensive evaluation model of Ch. indicum. And then sort with the relative proximity value. The results showed that the relative proximity was between 0.098 and 0.983 which represents there were significant differences in the scavenging effect of DPPH, ABTS and hydroxyl radical and the inhibition effect of xanthine oxidase(XOD) and lipoxygenase(LOX) between extracts of Ch. indicum from different areas. The Ch. indicum from Dabie Mountain area have a relatively high relative degree of measurement and high-quality ranking. Taken together, the quality of Ch. indicum.from the Dabie Mountain area is better. The index weight coefficient and the classification result of producing area are basically consistent with the result of principal component analysis. The results show that the TOPSIS method based on entropy weight method can be used to evaluate the comprehensive quality of Ch. indicum.


Assuntos
Chrysanthemum , Anti-Inflamatórios , Antioxidantes , Entropia , Extratos Vegetais
8.
Bioresour Technol ; 316: 123902, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738560

RESUMO

Tribonema minus was cultivated in different concentrations of sugarcane wastewater (SW) diluted with mBG-11 medium to produce biomass for biodiesel, bioproduct, and biomaterial production. The results showed that T. minus grew mixotrophically in 50%SW, with the highest biomass accumulation (7.86 g/L) and nutrient removal efficiency (84.85% of nitrogen, 62.57% of phosphorus, and 44.72% of COD). Excluding 100%SW, the chrysolaminarin and cellulose contents increased with increasing SW concentration; the highest contents of 8.11% and 25.69% dry weight were reached in 75%SW, respectively. Although fewer lipids and palmitoleic acid accumulated at higher SW concentrations, their productivities were significantly higher than those in the control due to the higher contribution of biomass. Moreover, the fatty acid profiles produced at the tested concentrations showed superior biodiesel properties. These findings suggested that the addition of mBG-11 medium to SW might be an effective strategy for valuable biomass production in T. minus and SW bioremediation.


Assuntos
Microalgas , Águas Residuárias , Biocombustíveis , Biomassa , Bengala , Nitrogênio/análise , Fósforo , Açúcares
9.
Int J Food Sci Nutr ; 67(7): 744-53, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27356952

RESUMO

We conducted a meta-analysis to systematically evaluate the association between antioxidants intake and pancreatic cancer risk. Relevant articles were retrieved from PUBMED and EMBASE databases and standard meta-analysis methods were applied. Finally a total of 18 studies were included. Comparing the highest with lowest categories, higher dietary intakes of selenium, vitamin C, vitamin E, ß-carotene and ß-cryptoxanthin were significantly associated with reduced pancreatic cancer risk (for selenium, pooled OR = 0.47, 95%CI 0.26-0.85; for vitamin C, pooled OR = 0.68, 95%CI 0.57-0.80; for vitamin E, pooled OR = 0.70, 95%CI 0.62-0.81; for ß-carotene, pooled OR = 0.74, 95%CI 0.56-0.98; for ß-cryptoxanthin, pooled OR = 0.70, 95%CI 0.56-0.88). Lycopene intake was marginally associated with pancreatic cancer risk (pooled OR = 0.85, 95%CI 0.73-1.00), while no significant association was observed for α-carotene, lutein and zeaxanthin. In summary, higher dietary intake of selenium, vitamin C, vitamin E, ß-carotene and ß-cryptoxanthin was inversely associated with pancreatic cancer risk.


Assuntos
Antioxidantes/farmacologia , Neoplasias Pancreáticas/epidemiologia , Ácido Ascórbico/administração & dosagem , beta-Criptoxantina/administração & dosagem , Carotenoides/administração & dosagem , Bases de Dados Factuais , Dieta , Humanos , Luteína/administração & dosagem , Licopeno , Fatores de Risco , Selênio/administração & dosagem , Vitamina E/administração & dosagem , Zeaxantinas/administração & dosagem , beta Caroteno/administração & dosagem
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