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1.
Molecules ; 28(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37687129

RESUMEN

One of the largest concerns with world health today is still antibiotic resistance, which is making it imperative to find efficient alternatives as soon as possible. It has been demonstrated that microbes are reliable sources for the creation of therapeutic antibiotics. This research intends to investigate the endophytic microorganisms from several medicinal plants in Fenghuang Mountain (Jiangsu Province, China) and to discover new antibiotics from their secondary metabolites. A total of 269 endophytic strains were isolated from nine distinct medicinal plants. Taxonomic analysis revealed that there were 20 distinct species among these endophytes, with Streptomyces being the most common genus. Three of the target strains were chosen for scale-up fermentation after preliminary screening of antibacterial activities and the metabolomics investigation using LC-MS. These strains were Penicillium sp. NX-S-6, Streptomyces sp. YHLB-L-2 and Streptomyces sp. ZLBB-S-6. Twenty-three secondary metabolites (1-23), including a new sorbicillin analogue (1), were produced as a result of antibacterial activity-guided isolation. Through spectroscopic analysis using MS and NMR, the structures of yield compounds were clarified. According to antibacterial data, S. aureus or B. subtilis were inhibited to varying degrees by sorrentanone (3), emodic acid (8), GKK1032 B (10), linoleic acid (14), toyocamycin (17) and quinomycin A (21). The most effective antimicrobial agent against S. aureus, B. subtilis, E. coli and A. baumannii was quinomycin A (21). In addition, quinomycin A showed strong antifungal activity against Aspergillus fumigatus, Cryptococcus neoformans, and two clinical isolated strains Aspergillus fumigatus #176 and #339, with MIC as 16, 4, 16 and 16 µg/mL, respectively. This is the first time that bioprospecting of actinobacteria and their secondary metabolites from medicinal plants in Fenghuang Mountain was reported. The finding demonstrates the potential of endophytic microbes in medical plants to produce a variety of natural products. Endophytic microbes will be an important source for new antibiotics.


Asunto(s)
Equinomicina , Plantas Medicinales , Antibacterianos/farmacología , Escherichia coli , Staphylococcus aureus
2.
Org Lett ; 22(10): 3739-3743, 2020 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-32186890

RESUMEN

A novel 6/6/5/6 tetracyclic polyketide named chartspiroton (1) was isolated from a medicinal plant endophytic Streptomyces in Dendrobium officinale. The complete structure assignment with absolute stereochemistry was elucidated through spectroscopic data, computational calculations, and single-crystal X-ray diffraction. Chartspiroton features an unprecedented naphthoquinone derivative spiro-fused with a benzofuran lactone moiety. A plausible polyketide biosynthetic pathway for 1 suggested intriguing oxidative rearrangement steps to form the five-membered lactone ring.


Asunto(s)
Lactonas/química , Naftoquinonas/química , Policétidos/química , Streptomyces/química , Vías Biosintéticas , Cristalografía por Rayos X , Estructura Molecular , Naftoquinonas/aislamiento & purificación , Plantas Medicinales , Policétidos/aislamiento & purificación , Análisis Espectral
3.
J Agric Food Chem ; 68(6): 1588-1595, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31994388

RESUMEN

The discovery of new, safe, and effective pesticides is one of the main means for modern crop protection and parasitic disease control. During the search for new insecticidal secondary metabolites from endophytes in Stemona sessilifolia (a traditional Chinese medicine with a long history as an insecticide), 10 new insecticidal endostemonines A-J (1-10) were identified from an endophytic Streptomyces sp. BS-1. Their structures were determined by comprehensive spectroscopic analysis. Endostemonines A-J represent the first reported naturally occurring pyrrole-2-carboxylic ester derivatives, which consisted of different fatty acid chains at the C-2 of pyrrole ring were produced by traditional Chinese medicine endophytic microbes. All new tested compounds exhibited strong lethal activity against Aphis gossypii (LC50 value range of 3.55-32.00 mg/L after 72 h). This research highlighted the discovery of pesticide natural products from insecticidal medicinal plant endophytes for the first time, paving a new pathway for the development of pest control.


Asunto(s)
Endófitos/química , Compuestos Heterocíclicos con 3 Anillos/metabolismo , Insecticidas/metabolismo , Stemonaceae/microbiología , Streptomyces/química , Streptomyces/metabolismo , Animales , Áfidos/efectos de los fármacos , Endófitos/metabolismo , Compuestos Heterocíclicos con 3 Anillos/química , Compuestos Heterocíclicos con 3 Anillos/toxicidad , Insecticidas/química , Insecticidas/toxicidad , Metabolismo Secundario
4.
Clin Interv Aging ; 13: 1313-1320, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30087557

RESUMEN

OBJECTIVE: Elderly people with mild cognitive impairment (MCI) are at high risk for dementia. This study compared the effects of standard cognitive training with a creative expression (CrExp) program. METHODS: Adult patients with MCI aged 60 years and older (N=93) were randomly assigned to either CrExp therapy (n=48) or a control group who received standard cognitive training (n=45) for 16 weeks. The Montreal Cognitive Assessment, Chinese Version of the Auditory Verbal Learning Test, Chinese Version of the Category Verbal Fluency Test, Digit Span Test, Trail Making Test, Chinese Version of Activities of Daily Living scale, and Memory Satisfaction Questionnaire were used to measure cognitive functioning and daily living abilities. Assessments were administered at baseline, postintervention, and 6 months follow-up. RESULTS: At postintervention, patients receiving CrExp therapy scored significantly higher than patients receiving standard cognitive training, in general cognitive functioning, memory, executive function, functional status, and everyday living ability. The improvements in cognitive functioning were maintained at the 6 month follow-up. CONCLUSION: CrExp therapy has greater positive effects on cognitive functions and daily living ability than standard cognitive training. This unique therapy may serve as a cost-effective adjunct to standard interventions for older adults with mild cognitive impairment.


Asunto(s)
Enfermedad de Alzheimer/prevención & control , Arteterapia/métodos , Disfunción Cognitiva/terapia , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Cognición , Función Ejecutiva , Femenino , Humanos , Masculino , Memoria
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 31(3): 331-3, 2011 Mar.
Artículo en Chino | MEDLINE | ID: mdl-21485072

RESUMEN

OBJECTIVE: To explore the pathologic mechanism of blood-stasis tongue figure (BSTF) formation in patients with primary dysmenorrhea. METHODS: Blood levels of platelet activating factor (PAF) and acetyl hydrolase of PAF (PAF-AH) in 41 patients with primary dysmenorrhea and 20 healthy subjects were detected by enzyme linked immunosorbent assay (ELISA). RESULTS: The level of PAF in the 22 patients with BSTF was 252. 214 +/- 37. 568 ng/L, which was higher than that in patients without BSTF (19 patients, 212.348 +/- 22.794 ng/L) and healthy subjects (182.126 +/- 18.306 ng/L) respectively, while level of PAF-AH showed an opposite sequence in them, i.e., 3.090 +/- 1.483, 5.382 +/- 1.873, and 5.607 +/- 2.073 ng/L, respectively (P < 0.05). Patients without BSTF showed only a higher level of PAF when compared with that in healthy subjects (P < 0.05). No significant difference in PAF or PAF-AH levels was shown among patients with BDTF of different Chinese medical syndrome types (P > 0.05). CONCLUSION: PAF level obviously increased and PAF-AH level obviously decreased in primary dysmenorrhea patients of BSTF, suggesting that the imbalance of PAF and PAF-AH was correlated with the pathologic mechanism of the BSTF formation in primary dysmenorrhea patients.


Asunto(s)
1-Alquil-2-acetilglicerofosfocolina Esterasa/sangre , Dismenorrea/diagnóstico , Medicina Tradicional China , Factor de Activación Plaquetaria/metabolismo , Adolescente , Estudios de Casos y Controles , Dismenorrea/sangre , Dismenorrea/patología , Femenino , Humanos , Lengua , Adulto Joven
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