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1.
J Agric Food Chem ; 71(48): 18963-18972, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37962281

RESUMEN

Fermented tea (FT) using a single Eurotium cristatum strain can produce a pleasant fungal-flowery aroma, which is similar to the composite aroma characteristic of minty, flowery, and woody aromas, but its molecular basis is not yet clear. In this study, solvent-assisted flavor evaporation and gas chromatography-mass spectrometry/olfactometry were applied to isolate and identify volatiles from the FT by E. cristatum. The application of an aroma extract dilution analysis screened out 43 aroma-active compounds. Quantification revealed that there were 11 odorants with high odor threshold concentrations. Recombination and omission tests revealed that nonanal, methyl salicylate, decanoic acid, 4-methoxybenzaldehyde, α-terpineol, phenylacetaldehyde, and coumarin were the major odorants in the FT. Addition tests further verified that methyl salicylate, 4-methoxybenzaldehyde, and coumarin were the key odorants for fungal-flowery aroma, each corresponding to minty, woody, and flowery aromas, respectively. 4-Methoxybenzaldehyde and coumarin were newly found odorants for fungal-flowery aroma in FT, and 4-methoxybenzaldehyde had not been reported as a tea volatile compound before. This finding may guide future industrial production optimization of FT with improved flavor.


Asunto(s)
Odorantes , Compuestos Orgánicos Volátiles , Odorantes/análisis , Olfato , Aromatizantes/análisis , Compuestos Orgánicos Volátiles/análisis , Olfatometría , Cumarinas/análisis ,
2.
Food Chem ; 411: 135487, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36669341

RESUMEN

The aim of this study was to reveal the molecular basis of aroma changes during storage of An tea (AT). The key volatile compounds in AT were screened using SPME-GC-MS and SPE-GC-MS analytical techniques in combination with odor activity value (OAV) and flavor dilution factor (FD). The results showed that with the increase of storage time the stale and woody aromas were revealed. Esters, acids and hydrocarbons are the main types of volatile compounds in AT, and their content accounts for 52.69 %-61.29 % of the total volatile compounds. The key volatile compounds with stale and woody aromas during AT storage were obtained by OAV value and FD value, namely ketoisophorone (flavor dilution factor, FD = 64), linalool oxide C (FD = 64), 1-octen-3-ol (OAV > 1, FD = 32), 1,2-dimethoxybenzene (FD = 16), naphthalene (OAV > 1, FD = 32), 3,4-dimethoxytoluene (FD = 16), and 1,2,3-trimethoxybenzene (FD = 8). Our research provides a scientific basis and insights for the improvement of quality during the storage of dark tea.


Asunto(s)
Odorantes , Compuestos Orgánicos Volátiles , Odorantes/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , , Compuestos Orgánicos Volátiles/análisis , Olfatometría/métodos
3.
Inorg Chem ; 61(44): 17494-17504, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36283080

RESUMEN

Although carbon monoxide (CO) has been known to bind to the ferrous heme in cytochrome P450 enzymes (P450s) since the earliest days of P450 research, details on the nature of the ferrous-CO bonding remain elusive. This study employed dispersion-corrected density functional theory (DFT) calculations and DFT-based theoretical analyses to investigate the complexes between CO and a thiolate- or imidazole-ligated heme that contains ferric or ferrous iron. Traditionally, the ferrous-CO bonding in heme systems has been interpreted qualitatively in terms of σ donation and π backdonation. Complementary occupied-virtual orbital pair (COVP) analysis yielded one orbital pair for σ donation and two for π backdonation together with the specific magnitude of their energetic contributions. The charge-transfer effect for these three orbital pairs has nearly the same energetic significance in the ferrous-CO complexes. Therefore, in total, the π-backdonation effect is much greater than the σ-donation effect. In contrast, the σ-donation effect is more significant in the ferric-CO complex because of the less efficient π backdonation. The nature of ferric-CO and ferrous-CO bonding was further scrutinized using the generalized Kohn-Sham energy decomposition analysis (GKS-EDA) scheme, whose results highlighted the significance of various effects in enhancing the Fe-CO bonding for the thiolate- and imidazole-ligated heme groups. In particular, the intrinsic repulsion effect plays a crucial role in promoting the preferential binding of CO toward the ferrous heme and in determining the geometry of the complexes.


Asunto(s)
Hemoproteínas , Hierro/química , Hemo/química , Monóxido de Carbono/química , Sistema Enzimático del Citocromo P-450 , Imidazoles
4.
Phytochemistry ; 187: 112761, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33933827

RESUMEN

Seven previously unidentified polycyclic polyprenylated acylphloroglucinol (PPAP) derivatives hypseudohenrins A-G, along with six known analogs, were isolated from the aerial portion of Hypericum pseudohenryi. Their structures were determined by NMR, ECD and X-ray crystallographic spectroscopy. These compounds were screened for anti-inflammatory activity, and hypseudohenrins B and G (at the concentration of 10 µM) showed NO production inhibition ratios of 52.56% and 54.01%, respectively, which imply good anti-inflammatory activity. In particular, uraloidin A exhibited an NO inhibition ratio of 90.61%, while that ratio of the positive control compound dexamethasone was 94.88%. Additionally, anti-cancer and neural-protective activities were screened, but none of these compounds showed desirable activity.


Asunto(s)
Hypericum , Antiinflamatorios/farmacología , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/farmacología
5.
J Asian Nat Prod Res ; 23(6): 536-544, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33779421

RESUMEN

Three previously unidentified polycyclic polyprenylated acylphloroglucinols (PPAPs) derivatives, hypseudohenrins I-K (1-3), along with a known analogue hyphenrone X (4), were isolated from the aerial part of Hypericum pseudohenryi. The structures of the new compounds were elucidated by NMR spectroscopy and ECD calculation. The anti-inflammatory activity of the compounds was evaluated. Compounds 1-3 showed mild anti-inflammatory activity while hyphenrone X showed prominent anti-inflammatory activity.[Formula: see text].


Asunto(s)
Hypericum , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/farmacología
6.
Mitochondrial DNA B Resour ; 6(1): 84-85, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33521276

RESUMEN

Scutellaria scordifolia Fisch. ex Schrank Li is a traditional Chinese medicinal plant of genus Scutellaria from the Labiatae family. The complete chloroplast genome of was 152,336 bp in length, which contained 133 complete genes including 87 protein-coding genes (87 PCGs), 8 ribosomal RNA genes (8 rRNAs), and 37 transfer RNA genes (37 tRNAs). The GC content of chloroplast DNA was 38.3%. The corresponding values of the LSC, SSC, and IR regions were 36.3%, 32.5%, and 43.6%, respectively. Phylogenetic tree showed that the species from genus Scutellaria were divided into two monophyletic clades, and the divergence time of S. scordifolia was earlier than that of the other species.

7.
J Asian Nat Prod Res ; 23(11): 1068-1076, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33565352

RESUMEN

Polycyclic polyprenylated acylphloroglucinols (PPAPs) were mainly obtained from the plants of Hypericum genus of Guttiferae family, and possessed intriguing chemical structures and appealing biological activities. Two new PPAPs derivatives, hyperacmosin C (1) and hyperacmosin D (2) were isolated from H. acmosepalum. Their structures were established by NMR, HREIMS, and experimental electronic circular dichroism spectra. Besides, compound 1 showed significant hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage and compound 2 could moderately increase the relative glucose consumption.


Asunto(s)
Hypericum , Dicroismo Circular , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol/farmacología
8.
J Asian Nat Prod Res ; 22(6): 521-530, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32186415

RESUMEN

Three new polycyclic polyprenylated acylphloroglucinol derivatives, hyperacmosins H-J (1-3), with four known compounds (4-7), were isolated from the air-dried aerial parts of Hypericum acmosepalum. Especially, compounds 1 and 2 were identified as methylated polycyclic polyprenylated acylphloroglucinol derivatives (mPPAPs). Their structures were established by NMR, HRESIMS and experimental electronic circular dichroism (ECD) spectra. The hepatoprotective activity of seven compounds were evaluated. Compounds 1 and 5 exhibited hepatoprotective activity against paracetamol-induced HepG2 cell damage.[Formula: see text].


Asunto(s)
Hypericum , Células Hep G2 , Espectroscopía de Resonancia Magnética , Estructura Molecular , Floroglucinol
9.
Fitoterapia ; 142: 104535, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32145311

RESUMEN

Three new homoadamantane-type polyprenylated acylphloroglucinols, hyperacmosins E-G (1-3), with seven known compounds were isolated from the air-dried aerial parts of Hypericum asmosepalum. Their structures were determined by NMR, HRESIMS and experimental electronic circular dichroism (ECD) spectra. The hepatoprotective activity of these compounds were evaluated. Compounds 4 and 8 exhibited hepatoprotective activity against paracetamol-induced HepG2 cell damage.


Asunto(s)
Hypericum/química , Floroglucinol/análogos & derivados , Compuestos Policíclicos/aislamiento & purificación , Adamantano/análogos & derivados , Adamantano/aislamiento & purificación , Células Hep G2 , Humanos , Compuestos Policíclicos/química , Sustancias Protectoras/aislamiento & purificación
10.
BMC Vet Res ; 15(1): 113, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30975135

RESUMEN

BACKGROUND: In May 2017, 17 dogs in a German Shepherd breeding kennel in northern China developed respiratory clinical signs. The owner treated the dogs with an intravenous injection of Shuang-Huang-lian, a traditional Chinese medicine, and azithromycin. The respiratory signs improved 3 days post-treatment, however, cysts were observed in the necks of eight dogs, and three of them died in the following 2 days. CASE PRESENTATION: Quantitative real-time PCR was used to detect canine influenza virus (CIV). All of the dogs in this kennel were positive and the remaining 14 dogs had seroconverted. Two of the dogs were taken to the China Agricultural University Veterinary Teaching Hospital for further examination. Two strains of influenza virus (A/canine/Beijing/0512-133/2017 and A/canine/Beijing/0512-137/2017) isolated from the nasal swabs of these dogs were sequenced and identified as avian-origin H3N2 CIV. For the two dogs admitted to the hospital, hematology showed mild inflammation and radiograph results indicated pneumonia. Cyst fluid was plated for bacterial culture and bacterial 16 s rRNA gene PCR was performed, followed by Sanger sequencing. The results indicated an Enterococcus faecalis infection. Antimicrobial susceptibility tests were performed and dogs were treated with enrofloxacin. All 14 remaining dogs recovered within 16 days. CONCLUSIONS: Coinfection of H3N2 CIV and Enterococcus faecalis was detected in dogs, which has not been reported previously. Our results highlight that CIV infection might promote the secondary infection of opportunistic bacteria and cause more severe and complicated clinical outcomes.


Asunto(s)
Coinfección/veterinaria , Enfermedades de los Perros/virología , Infecciones por Bacterias Grampositivas/veterinaria , Subtipo H3N2 del Virus de la Influenza A , Infecciones por Orthomyxoviridae/veterinaria , Animales , China/epidemiología , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/virología , Brotes de Enfermedades/veterinaria , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Perros/virología , Enterococcus faecalis , Femenino , Infecciones por Bacterias Grampositivas/complicaciones , Infecciones por Bacterias Grampositivas/microbiología , Subtipo H3N2 del Virus de la Influenza A/genética , Masculino , Infecciones por Orthomyxoviridae/complicaciones , Infecciones por Orthomyxoviridae/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
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