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1.
Nat Prod Res ; : 1-8, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38824679

RESUMEN

This study attempts to reveal antioxidants in the plant parts of Myxopyrum smilacifolium (Wall.) Blume using antioxidant assays and LC-MS/MS analysis. Methanol is the most effective solvent for collecting antioxidants. The roots-derived methanol extract demonstrates the greatest antioxidant activity, corresponding to the extremely low IC50 values of 16.39 µg/mL and 19.80 µg/mL for DPPH and ABTS radicals, respectively. The high phenolic and flavonoid contents are the primary reason for outstanding total antioxidant capacity (TAC; i.e. 247.73 ± 1.62 mg GA/g or 163.93 ± 0.83 mg AS/g) of the root extract. LC-MS/MS quantification of five phenolic compounds reveals exceptionally high amounts of quercetin and luteolin in the root extract, ranging from 238.86 ± 5.74 to 310.99 ± 1.44 µg/g and from 201.49 ± 7.84 to 234.10 ± 2.54 µg/g, respectively, in the root-derived methanol extract. The achievement highlights M. smilacifolium as a promising source of natural antioxidants for large-scale medical applications.

2.
Nat Prod Res ; 38(1): 60-67, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-35867000

RESUMEN

Two new sesquiterpenoids, homalolides C - D (1‒2), were co-isolated from the rhizomes of Homalomena pendula (Blume) Bakh.f collected in Vietnam with five known ones, aromadendrane-4α,10α-diol (3), bullatantriol (4), 1ß,4ß,6α-trihydroxy-eudesmane (5), 1ß,4ß,6ß-trihydroxyeudesmane (6), and 1ß,4ß,7α-trihydroxy-eudesmane (7). The structures and relative configuration of new compounds were elucidated by 1 D-/2D-NMR, IR, UV and HRESIMS analyses, and by comparisons to the reported data in the literature. Homalolide C presented an unprecedented skeleton with the 4/8 bicyclic system. All isolates did not exhibit appreciable inhibitory effects on LPS-induced NO production in the RAW 264.7 macrophage cell line and on the growth of human lung cancer cell line (SK-LU-1).


Asunto(s)
Araceae , Sesquiterpenos de Eudesmano , Sesquiterpenos , Ratones , Animales , Humanos , Rizoma/química , Sesquiterpenos/química , Línea Celular , Sesquiterpenos de Eudesmano/análisis , Células RAW 264.7 , Araceae/química , Estructura Molecular
3.
Thyroid ; 34(2): 215-224, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38149602

RESUMEN

Background: Despite the excellent disease-specific survival associated with low-risk differentiated thyroid cancer (DTC), its diagnosis and management have been linked to patient concerns about cancer recurrence, treatment-related health risks, and mortality. Lack of information regarding long-term health outcomes can perpetuate these concerns. Therefore, we assessed all-cause and cause-specific mortality in a large cohort of individuals diagnosed with low-risk DTC. Methods: From the U.S. Surveillance, Epidemiology, and End Results-12 cancer registry database (1992-2019), we identified 51,854 individuals (81.8% female) diagnosed with first primary DTC at low risk of recurrence (≤4 cm, localized). We estimated cause-specific cumulative mortality by time since diagnosis, accounting for competing risks. Standardized mortality ratios (SMRs) and CIs were used to compare observed mortality rates in DTC patients with expected rates in the matched U.S. general population, overall and by time since DTC diagnosis. We used Cox proportional hazards models to examine associations between radioactive iodine (RAI) treatment and cause-specific mortality. Results: During follow-up (median = 8.8, range 0-28 years), 3467 (6.7%) deaths were recorded. Thyroid cancer accounted for only 4.3% of deaths (n = 148). The most common causes of death were malignancies (other than thyroid cancer) (n = 1031, 29.7%) and cardiovascular disease (CVD; n = 912, 26.3%). The 20-year cumulative mortality rate from thyroid cancer, malignancies (other than thyroid or nonmelanoma skin cancer), and CVD was 0.6%, 4.6%, and 3.9%, respectively. Lower than expected mortality was observed for all causes excluding thyroid cancer (SMR = 0.69 [CI 0.67-0.71]) and most specific causes, including all malignancies combined (other than thyroid cancer; SMR = 0.80 [CI 0.75-0.85]) and CVD (SMR = 0.64 [CI 0.60-0.69]). However, mortality rates were elevated for specific cancers, including pancreas (SMR = 1.58 [CI 1.18-2.06]), kidney and renal pelvis (SMR = 1.85 [CI 1.10-2.93]), and brain and other nervous system (SMR = 1.62 [CI 0.99-2.51]), and myeloma (SMR = 2.35 [CI 1.46-3.60]) and leukemia (SMR = 1.62 [CI 1.07-2.36]); these associations were stronger ≥10 years after diagnosis. RAI was not associated with risk of cause-specific death, but numbers of events were small and the range of administered activities was likely narrow. Conclusions: Overall, our findings provide reassurance regarding low overall and cause-specific mortality rates in individuals with low-risk DTC. Additional research is necessary to confirm and understand the increased mortality from certain subsequent cancers.


Asunto(s)
Adenocarcinoma , Supervivientes de Cáncer , Enfermedades Cardiovasculares , Neoplasias , Neoplasias de la Tiroides , Humanos , Femenino , Estados Unidos/epidemiología , Masculino , Neoplasias de la Tiroides/complicaciones , Causas de Muerte , Radioisótopos de Yodo , Enfermedades Cardiovasculares/epidemiología
4.
Nat Prod Res ; : 1-10, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36803113

RESUMEN

Five sesquiterpenoids including 2α-hydroxyoplopanone (1), oplopanone (2), 1ß,4ß,6α-trihydroxy-eudesmane (3), 1ß,4ß,7α-trihydroxy-eudesmane (4) and bullatantriol (5) were isolated from Homalomena pendula. The structure of the previously reported compound, 5,7-diepi-2α-hydroxyoplopanone (1a), has been revised to 1 by the spectroscopic evidences (1D-/2D-NMR, IR, UV and HRESIMS) and by comparison between experimental and theoretical NMR data using DP4+ protocol. Furthermore, the absolute configuration of 1 was unambiguously assigned by ECD experiments. Compounds 2 and 4 displayed a potent ability to stimulate osteogenic differentiation of MC3T3-E1 cells at 4 µg/mL (by 123.74% and 131.07%, respectively) and 20 µg/mL (by 112.45% and 126.41%, respectively) whilst 3 and 5 did not show any activities. At 20 µg/mL, 4 and 5 significantly promoted the mineralization of MC3T3-E1 cells with values of 112.95% and 116.37%, respectively, whereas 2 and 3 were inactive. The results indicated that 4 could be an excellent component for anti-osteoporosis studies from the rhizomes of H. pendula.

5.
Cancers (Basel) ; 15(4)2023 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-36831509

RESUMEN

(Multi-)Morbidity shares common biological mechanisms or risk factors with breast cancer. This study aimed to investigate the association between the number of morbidities and patterns of morbidity and the risk of female breast cancer. Among 239,436 women (40-69 years) enrolled in the UK Biobank cohort who had no cancer history at baseline, we identified 35 self-reported chronic diseases at baseline. We assigned individuals into morbidity patterns using agglomerative hierarchical clustering analysis. We fitted Cox models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for breast cancer risk. In total, 58.4% of women had at least one morbidity, and the prevalence of multi-morbidity was 25.8%. During a median 7-year follow-up, there was no association between breast cancer risk (5326 cases) and either the number of morbidities or the identified clinically relevant morbidity patterns: no-predominant morbidity (reference), psychiatric morbidities (HR = 1.04, 95%CI 0.94-1.16), respiratory/immunological morbidities (HR = 0.98, 95%CI 0.90-1.07), cardiovascular/metabolic morbidities (HR = 0.93, 95%CI 0.81-1.06), and unspecific morbidities (HR = 0.98, 95%CI 0.89-1.07), overall. Among women younger than 50 years of age only, however, there was a significant association with psychiatric morbidity patterns compared to the no-predominant morbidity pattern (HR = 1.25, 95%CI 1.02-1.52). The other associations did not vary when stratifying by age at baseline and adherence to mammography recommendations. In conclusion, multi-morbidity was not a key factor to help identify patients at an increased risk of breast cancer.

6.
Nat Prod Res ; 37(21): 3595-3604, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35788165

RESUMEN

A new spirostanol steroid, aspidiata A (1), and a new spirostanol steroidal saponin, aspidiata B (2), along with three known compounds, paris saponin VII (3), daucosterol (4), and (25R)-spirostane-1ß,2ß,3ß,4ß,5ß,6ß-hexol (5), were isolated from whole plants of Aspidistra triradiata collected in Vietnam. Their chemical structures were established by spectroscopic analysis and comparison with previously published data. Compound 3 showed strong cytotoxicity against LU-1, Hep-G2, MCF-7, and KB human cancer cell lines with half maximal inhibitory concentration (IC50) values ranging from 0.57 to 1.23 µM. Compound 5 exhibited weak cytotoxic activity against the LU-1 cell line, with an IC50 value of 95.81 µM.

7.
Endocr Relat Cancer ; 30(1)2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36256851

RESUMEN

In a previous systematic review and meta-analysis of studies reporting associations between hyper-/hypothyroidism and breast cancer incidence published through 29 January 2019, we identified a higher risk with diagnosed hyperthyroidism compared to euthyroidism, but no association with diagnosed hypothyroidism. This 2-year updated meta-analysis aims to investigate the role of menopause in this association and the dose-response relationship with blood levels of thyroid-stimulating hormone (TSH) and thyroid hormones. After the exclusion of studies with only mortality follow-up, with thyroid dysfunction evaluated as a cancer biomarker or after prior breast cancer diagnosis, we reviewed 25 studies that were published up to 01 December 2021 and identified in MEDLINE, the COCHRANE library, Embase, or Web of Science; of these, 9 were included in the previous meta-analysis. Risk estimates from 22 of the 25 studies were included in the meta-analysis and pooled using random-effects models. Compared to euthyroidism, hyperthyroidism and hypothyroidism diagnoses were associated with higher (pooled risk ratio (RR): 1.12, 95% CI: 1.06-1.18, 3829 exposed cases) and lower risks (RR = 0.93, 95% CI: 0.86-1.00, 5632 exposed cases) of breast cancer, respectively. The increased risk after hyperthyroidism was greater among postmenopausal women (RR = 1.19, 95% CI 1.09-1.30) and the decreased risk after hypothyroidism was more pronounced among premenopausal women (RR = 0.69, 95% CI 0.53-0.89). Among women with no prior history of thyroid disease, every 1 mIU/L increase in TSH level was associated with a 0.8% (95% CI > 0-1.5%) lower risk of breast cancer. In conclusion, this meta-analysis supports an association between thyroid hormone levels and breast cancer risk, which could be modified by menopausal status.


Asunto(s)
Neoplasias de la Mama , Hipertiroidismo , Hipotiroidismo , Enfermedades de la Tiroides , Femenino , Humanos , Neoplasias de la Mama/complicaciones , Enfermedades de la Tiroides/complicaciones , Hipertiroidismo/complicaciones , Hipertiroidismo/epidemiología , Hipotiroidismo/epidemiología , Tirotropina , Hormonas Tiroideas
8.
Nat Prod Res ; 37(15): 2559-2567, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35337228

RESUMEN

Sixteen sesquiterpenoids including two new ones, homalolides A - B (1‒2), were firstly isolated from the methanolic extract of the rhizomes of Homalomena pendula collected in Vietnam. The structures and relative stereochemistry of new compounds were elucidated by 1D-/2D-NMR, IR, UV and HRESIMS analyses. The GCMS experiment demonstrated that homalolide A (1) is an artifact due to the methylation during methanolic extraction process. All isolates (1‒16) were tested for their inhibitory activities against lipopolysaccharide-induced nitric oxide production in the RAW 264.7 macrophage cell line. Compounds 1, 3, 6‒8, 10‒12 displayed moderate inhibitory effect on NO production with IC50 values ranging from 35.41 to 64.06 µM.


Asunto(s)
Araceae , Sesquiterpenos , Animales , Ratones , Rizoma/química , Células RAW 264.7 , Macrófagos , Sesquiterpenos/química , Araceae/química , Antiinflamatorios/química , Óxido Nítrico , Estructura Molecular
9.
Br J Cancer ; 127(12): 2118-2124, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36224404

RESUMEN

BACKGROUND: Female thyroid cancer survivors are more likely to have a higher risk of breast cancer compared to the general population, and the underlying causes are yet to be understood. The potential role of I-131 treatment on this association remains controversial. METHODS: We pooled individual data of women who were treated for differentiated thyroid cancer from 1934 to 2005 in France, Italy and Sweden. Standardized incidence ratios (SIRs) for breast cancer were estimated by comparison with age, sex and calendar-year expected values of the general population in each country. We estimated breast cancer risk in relation to I-131 treatment using time-dependent Poisson models. RESULTS: Of 8475 women (mean age at diagnosis: 45 years, range 2-90 years), 335 were diagnosed with breast cancer [SIR = 1.52, 95% confidence interval (CI): 1.36-1.69] during a median follow-up time of 12.7 years since diagnosis. Overall, breast cancer risk did not differ between women treated or not with I-131 (relative risk=1.07, 95% CI 0.84-1.35). However, breast cancer risk increased with increasing cumulative I-131 activity, without significant departure from linearity (excess relative risk per 100 mCi=17%, 95% CI: 2% to 38%). The higher risk associated with a cumulative I-131 activity of ≥100 mCi and ≥400 mCi was translated into 4 (95% CI -4 to 13) and 42 (95% CI -8 to 93) excess breast cancer cases per 10,000 person-years, respectively. CONCLUSIONS: An elevated risk was observed for the highest cumulative administered activity (>=400 mCi), and a significant dose-dependent association was observed among thyroid cancer survivors who were treated with I-131. However, overall, I-131 treatment might only explain partly the increase in breast cancer risk among female thyroid cancer survivors.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Neoplasias de la Tiroides , Femenino , Humanos , Preescolar , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Radioisótopos de Yodo/efectos adversos , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/radioterapia , Riesgo , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/etiología , Neoplasias de la Tiroides/radioterapia
10.
PLoS One ; 17(6): e0269789, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35696374

RESUMEN

Pesticide residue in food, especially in vegetables, is one of the important parameters to assess food safety. This study evaluates the pesticide use in vegetables from two provinces in Central Vietnamand and present data on pesticides detected in vegetables sampled from the sites. The potential health risk associated with the contamination of four commonly used pesticides in different vegetables is also discussed. Both household surveys and monitoring campaigns were conducted. The survey showed that improper pesticide application, storage, and waste disposal prevailed at the study sites. Only 20% of the respondent were aware of pesticide toxicity. As a result, pesticides were detected in 81% out of 290 vegetable samples collected at harvesting time. Up to 23% of samples had pesticide residues above the Maximum Residue Limit values. The highest total pesticide concentration quantified in vegetables in Thua Thien Hue was 11.9 mg/kg (green onions), and in Quang Binh was 38.6 mg/kg (mustard greens). Median residue levels of individual pesticides in vegetables ranged from 0.007 to 0.037 mg/kg. Among the ten target pesticides, cypermethrin, difenoconazole, and fenobucarb were detected at the highest frequencies (72%, 41%, and 37%, respectively). Pesticide residues varied between seasons at both study provinces. Pesticide contamination in the wet season was significantly higher than in the dry season. This study also discovered a potential health risk associated with fipronil residues in vegetables in Thua Thien Hue province. The paper provides recommendations for mitigation measures (both technological and social) in reducing potential health risks linked to pesticide use in vegetables in the region.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Contaminación de Alimentos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Verduras/química , Vietnam
11.
ACS Omega ; 7(11): 9397-9405, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35350314

RESUMEN

A novel polysaccharide structure (PS-T80) was collected from Ophiocordyceps sobolifera biomass and characterized via a combination of chemical and spectral analyses. Employing high-performance gel permeation chromatography (HPGPC), the average molecular weight is proven to be 7.4 × 104 Da. Furthermore, a sugar composition analysis of the obtained polysaccharide suggests two main sugars, ß-d-glucose and α-d-mannose, at a molar ratio of 2:1, respectively, in the backbone. The structure analysis unveils that PS-T80 is a mannoglucan, possessing the repeating unit of [→3)-ß-d-Glcp-(1 → 3)-α-d-Manp-(1 → 3)-ß-d-Glcp-(1→] n . Such a configuration could be considered a novel polysaccharide. Impressively, in vitro antioxidant tests revealed that PS-T80 has a promising antioxidant activity. These results demonstrate that the obtained PS is a potential bioactive material for biomedical applications.

12.
ACS Omega ; 7(51): 47923-47932, 2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36591194

RESUMEN

The presented study attempts to unveil and evaluate the antioxidant activity of a novel heteropolysaccharide separated from the roots of Myxopyrum smilacifolium (denoted as PS-MSR). The molecular weight of PS-MSR is found to be 1.88 × 104 Da and contains two principal sugars, which are d-glucose and d-fructose, in the backbone. Decoding the structure of the obtained PS-MSR sample has disclosed a novel polysaccharide for the first time. Indeed, the PS-MSR is composed of (1 → 3)-linked glucosyl units and (2 → 3)-linked fructosyl units. In addition, the 1D and 2D NMR spectra of the PS-MSR sample display the repeating unit of the isolated polysaccharide, [→3)-α-d-Glcp-(1 → 3)-ß-d-Frucf-(2 → 3)-ß-d-Frucf-2 → 3)-)-ß-d-Frucf-ß-(2→] n . Interestingly, the PS-MSR sample exhibits outstanding antioxidant activity, signifying the potential utilization of the explored polysaccharide for antioxidant-based material.

13.
Cancer Med ; 10(13): 4604-4614, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34041857

RESUMEN

This study aimed to evaluate the association between thyroid dysfunction and breast cancer risk. We included 239,436 females of the UK Biobank cohort. Information on thyroid dysfunction, personal and family medical history, medications, reproductive factors, lifestyle, and socioeconomic characteristics was retrieved from baseline self-reported data and hospital inpatient databases. Breast cancer diagnoses were identified through population-based registries. We computed Cox models to estimate hazard ratios (HRs) of breast cancer incidence for thyroid dysfunction diagnosis and treatments, and examined potential confounding and effect modification by comorbidities and breast cancer risk factors. In our study, 3,227 (1.3%) and 20,762 (8.7%) women had hyper- and hypothyroidism prior to the baseline. During a median follow-up of 7.1 years, 5,326 (2.2%) women developed breast cancer. Compared to no thyroid dysfunction, there was no association between hypothyroidism and breast cancer risk overall (HR = 0.93, 95% confidence interval (CI): 0.84-1.02, 442 cases), but we found a decreased risk more than 10 years after hypothyroidism diagnosis (HR=0.85, 95%CI 0.74-0.97, 226 cases). There was no association with hyperthyroidism overall (HR=1.08, 95%CI 0.86-1.35, 79 cases) but breast cancer risk was elevated among women with treated hyperthyroidism (HR=1.38, 95%CI: 1.03-1.86, 44 cases) or aged 60 years or more at hyperthyroidism diagnosis (HR=1.74, 95%CI: 1.01-3.00, 113 cases), and 5-10 years after hyperthyroidism diagnosis (HR=1.58, 95%CI: 1.06-2.33, 25 cases). In conclusion, breast cancer risk was reduced long after hypothyroidism diagnosis, but increased among women with treated hyperthyroidism. Future studies are needed to determine whether the higher breast cancer risk observed among treated hyperthyroidism could be explained by hyperthyroidism severity, type of treatment or aetiology.


Asunto(s)
Neoplasias de la Mama/etiología , Hipertiroidismo/complicaciones , Hipotiroidismo/complicaciones , Adulto , Factores de Edad , Anciano , Neoplasias de la Mama/epidemiología , Estudios de Cohortes , Intervalos de Confianza , Femenino , Humanos , Hipertiroidismo/epidemiología , Hipertiroidismo/terapia , Hipotiroidismo/epidemiología , Incidencia , Persona de Mediana Edad , Prevalencia , Modelos de Riesgos Proporcionales , Factores de Riesgo , Reino Unido/epidemiología
14.
J Asian Nat Prod Res ; 23(8): 754-763, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32608253

RESUMEN

Three new compounds (methyl-3ß,25-dihydroxycycloart-23-en-29-oate 3-sulfate (1), methyl-3ß-hydroxy-25-methoxycycloart-23-en-29-oate 3-sulfate (2) and 3ß-hydroxy-25-methoxycycloart-23-ene 3-sulfate (3)) and a known one (3ß-hydroxycycloart-24-en-23-one 3-sulfate (4)) were isolated from Vietnamese red alga Tricleocarpa fragilis. All isolated compounds 1-4 showed potent inhibitory activity against yeast α-glucosidase with IC50 values of 16.62 ± 2.80, 36.34 ± 4.04, 30.19 ± 5.01 and 6.52 ± 0.17 µM, respectively. The docking data showed that the substitutions at C-3 and the differences in the side chain of cycloartane-skeleton could influence the interaction of molecule with enzyme, which was consistent with the experimental findings.[Formula: see text].


Asunto(s)
Rhodophyta , Triterpenos , Pueblo Asiatico , Inhibidores de Glicósido Hidrolasas/farmacología , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Sulfatos , Triterpenos/farmacología , alfa-Glucosidasas/metabolismo
15.
Phytochemistry ; 183: 112630, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33378718

RESUMEN

Nine undescribed sesquiterpenes, which include five guaiane and four humulene-type, were isolated from the agarwood of Aquilaria malaccensis. The structures of these undescribed sesquiterpenes were elucidated by spectroscopic methods including UV, HRESI-MS, 1D and 2D-NMR, ECD, and X-ray diffraction (Cu Kα). The isolated compounds were tested for their inhibitory effect against LPS-induced NO production in RAW 264.7 cells. In particular, one sesquiterpene (1α,7α-dihydroxy-8oxo-4αH,5αH-guaia-9(10),11(13)-dien-12-oate) showed significant inhibition of NO production in LPS-stimulated macrophage RAW 264.7 cells with an IC50 value of 18.8 µM.


Asunto(s)
Sesquiterpenos , Thymelaeaceae , Animales , Antiinflamatorios/farmacología , Ratones , Estructura Molecular , Células RAW 264.7 , Sesquiterpenos/farmacología
16.
Acta Pharmaceutica Sinica B ; (6): 1629-1647, 2021.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-888825

RESUMEN

Chronic inflammation results from excessive pro-inflammatory signaling and the failure to resolve the inflammatory reaction. Lipid mediators orchestrate both the initiation and resolution of inflammation. Switching from pro-inflammatory to pro-resolving lipid mediator biosynthesis is considered as efficient strategy to relieve chronic inflammation, though drug candidates exhibiting such features are unknown. Starting from a library of Vietnamese medical plant extracts, we identified isomers of the biflavanoid 8-methylsocotrin-4'-ol from

17.
Polymers (Basel) ; 12(7)2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32664338

RESUMEN

This study aimed at providing a route towards the production of a novel exopolysaccharide (EPS) from fermented bamboo shoot-isolated Lactobacillus fermentum. A lactic acid bacteria strain, with high EPS production ability, was isolated from fermented bamboo shoots. This strain, R-49757, was identified in the BCCM/LMG Bacteria Collection, Ghent University, Belgium by the phenylalanyl-tRNA synthetase gene sequencing method, and it was named Lb. fermentum MC3. The molecular mass of the EPS measured via gel permeation chromatography was found to be 9.85 × 104 Da. Moreover, the monosaccharide composition in the EPS was analyzed by gas chromatography-mass spectrometry. Consequently, the EPS was discovered to be a heteropolysaccharide with the appearance of two main sugars-D-glucose and D-mannose-in the backbone. The results of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy analyses prove the repeating unit of this polysaccharide to be [→6)-ß-D-Glcp-(1→3)-ß-D-Manp-(1→6)-ß-D-Glcp-(1→]n, which appears to be a new EPS. The obtained results open up an avenue for the production of novel EPSs for biomedical applications.

19.
ChemistrySelect ; 5(21): 6312-6320, 2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32572383

RESUMEN

GC-MS was applied to identify 24 main substances in Melaleuca cajuputi essential oil (TA) extracted from fresh cajeput leaves through steam distilling. The inhibitory capability of active compounds in the TA from Thua Thien Hue, Vietnam over the Angiotensin-Converting Enzyme 2 (ACE2) protein in human body - the host receptor for SARS-CoV-2 and the main protease (PDB6LU7) of the SARS-CoV-2 using docking simulation has been studied herein. The results indicate that the ACE2 and PDB6LU7 proteins were strongly inhibited by 10 out of 24 compounds accounting for 70.9% in the TA. The most powerful anticoronavirus activity is expressed in the order: Terpineol (TA2) ≈ Guaiol (TA5) ≈ Linalool (TA19) > Cineol (TA1) > ß-Selinenol (TA3) > α-Eudesmol (TA4) > γ-Eudesmol (TA7). Interestingly, the synergistic interactions of these 10 substances of the TA exhibit excellent inhibition into the ACE2 and PDB6LU7 proteins. The docking results orient that the natural Melaleuca cajuputi essential oil is considered as a valuable resource for preventing SARS-CoV-2 invasion into human body.

20.
ACS Omega ; 5(14): 8312-8320, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32363255

RESUMEN

Eighteen active substances, including 17 organosulfur compounds found in garlic essential oil (T), were identified by GC-MS analysis. For the first time, using the molecular docking technique, we report the inhibitory effect of the considered compounds on the host receptor angiotensin-converting enzyme 2 (ACE2) protein in the human body that leads to a crucial foundation about coronavirus resistance of individual compounds on the main protease (PDB6LU7) protein of SARS-CoV-2. The results show that the 17 organosulfur compounds, accounting for 99.4% contents of the garlic essential oil, have strong interactions with the amino acids of the ACE2 protein and the main protease PDB6LU7 of SARS-CoV-2. The strongest anticoronavirus activity is expressed in allyl disulfide and allyl trisulfide, which account for the highest content in the garlic essential oil (51.3%). Interestingly, docking results indicate the synergistic interactions of the 17 substances, which exhibit good inhibition of the ACE2 and PDB6LU7 proteins. The results suggest that the garlic essential oil is a valuable natural antivirus source, which contributes to preventing the invasion of coronavirus into the human body.

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