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1.
Molecules ; 29(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338301

RESUMO

American ginseng, a highly valuable crop in North America, is susceptible to various diseases caused by fungal pathogens, including Alternaria spp., Fusarium spp., and Pestalotiopsis spp. The development of alternative control strategies that use botanicals to control fungal pathogens in American ginseng is desired as it provides multiple benefits. In this study, we isolated and identified three fungal isolates, Alternaria panax, Fusarium sporotrichioides, and Pestalotiopsis nanjingensis, from diseased American ginseng plants. Ethanolic and aqueous extracts from the roots and leaves of goldenseal were prepared, and the major alkaloid constituents were assessed via liquid chromatography-mass spectrometry (LC-MS). Next, the antifungal effects of goldenseal extracts were tested against these three fungal pathogens. Goldenseal root ethanolic extracts exhibited the most potent inhibition against fungal growth, while goldenseal root aqueous extracts and leaf ethanolic extracts showed only moderate inhibition. At 2% (m/v) concentration, goldenseal root ethanolic extracts showed an inhibition rate of 86.0%, 94.9%, and 39.1% against A. panax, F. sporotrichioides, and P. nanjingensis, respectively. The effect of goldenseal root ethanolic extracts on the mycelial morphology of fungal isolates was studied via scanning electron microscopy (SEM). The mycelia of the pathogens treated with the goldenseal root ethanolic extract displayed considerable morphological alterations. This study suggests that goldenseal extracts have the potential to be used as a botanical fungicide to control plant fungal diseases caused by A. panax, F. sporotrichioides, or P. nanjingensis.


Assuntos
Alcaloides , Hydrastis , Panax , Hydrastis/química , Raízes de Plantas/química , Alcaloides/química , Extratos Vegetais/farmacologia , Extratos Vegetais/análise
2.
Plant Dis ; 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890123

RESUMO

American ginseng (Panax quinquefolius L.) is an herbaceous perennial understory plant. It was listed as endangered species by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (McGraw et al. 2013). Leaf spot symptoms were observed on 6-year-old cultivated American ginseng on a research plot (8 x 12 ft raised bed under a tree canopy) in Rutherford Co., TN in July 2021 (Fig. 1a). Symptomatic leaves were exhibiting light brown leaf spots with chlorotic haloes 0.5 to 0.8 cm in diameter, mostly confined within or bounded by veins. As the disease progressed, leaf spots expanded and coalesced into irregular shapes with necrotic centers, resulting in a tattered appearance of the leaf. Disease severity was about 50 to 80% of leaf area and incidence was 10% out of 20 plants. Plant tissues were surface sterilized with 10% NaOCl2 for 60s and washed thrice with sterile water and plated on potato dextrose agar (PDA). Colony growth of the isolates FBG880 and FBG881 on PDA were round, white, thick, and flocculent at the front of the plate and showed a yellowish-ringed shape on the back 10 days after incubation at 25°C (light/dark: 12/12h). Acervular conidiomata containing abundant conidia were observed on PDA. They were globose, 1.0 to 1.8 mm in diameter, and found as solitary or aggregated clusters. Conidia contained five cells (average 13.03±3.50 x 14.31±3.93 µm, n = 30). The middle three cells were light brown to brown. The basal and apical cells were nearly triangular, and transparent, with two to three (7:3 ratios, respectively) apical appendages (average 13.27±3.27 µm) and a basal appendage (average 4.50±0.95 µm, n = 30). To determine pathogen identity, total DNA was extracted using DNeasy PowerLyzer Microbial Kit from fungal colonies on PDA (isolates FBG880 and FBG881). The ribosomal internal transcribed spacer (ITS) region, beta-tubulin (BT), and translation elongation factors 1-α (EF1) genetic markers were amplified using ITS1/ITS4 (White et al. 1990), T1/T2 (Stefanczyk et al. 2016), and EF1/EF2 (O'Donnell et al. 1998), respectively. The sequences (GenBank accession nos. ITS: OQ102470 and OQ103415; BT: OQ107059 and OQ107061; and EF1: OQ107060 and OQ107062) are 100% similar to Pestalotiopsis nanjingensis (CSUFTCC16 and CFCC53882) (Jiang et al. 2022; Li et al. 2021) (Fig. 2). Based on morphology and molecular characteristics, the isolates were identified as P. nanjingensis. To conduct the pathogenicity trial, six healthy 1-year-old American ginseng plants, germinated from seeds and grown in the greenhouse were spray inoculated with a conidial suspension (1×106 conidia/ml) (FBG880). Six control plants were sprayed with sterile water. All plants were covered with plastic bags and incubated in a greenhouse set at 21 to 23°C, 70% relative humidity and 16-h photoperiod. After 48 h, bags were removed and plants were maintained under the same conditions. After one month, while control plants remained asymptomatic (Fig. 1b), inoculated plants started to exhibit symptoms resembling those in the research plot (Fig. 1c). Fungal isolates resembling P. nanjingensis in cultural characters were consistently recovered from inoculated plants and their identity as P. nanjingensis was confirmed by DNA sequencing. To our knowledge, this is the first report of leaf spot disease caused by P. nanjingensis on American ginseng. Identification of this pathogen and confirmation of its pathogenicity are fundamental to future disease management approaches.

4.
Nat Rev Cardiol ; 9(8): 464-77, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22525668

RESUMO

Cardiovascular disease (CVD) is an under-recognized major health problem among women in South-East Asia. The prevalence of cardiovascular risk factors such as hypertension, diabetes mellitus, dyslipidemia, physical inactivity, and being overweight or obese has shown a significantly increasing trend among women in the region, with the exception of Singapore. The problem is compounded by low awareness that CVD is a health problem for women as well as for men, by misconceptions about the disease, and by the lack of suitable, locally available health literature. Efforts have been made by the national heart associations and other organizations to increase heart health awareness and promote healthy lifestyles. Singapore initiated these prevention programs in the early 1990s and has been successful in reducing the prevalence of cardiovascular risk factors. The governments of the region, in accordance with the Noncommunicable Disease Alliance, have begun implementing appropriate preventive strategies and improving health-delivery systems. However, psychological, social, and cultural barriers to cardiovascular health awareness in women need to be addressed before these programs can be fully and successfully implemented.


Assuntos
Doenças Cardiovasculares/epidemiologia , Saúde da Mulher , Sudeste Asiático/epidemiologia , Doenças Cardiovasculares/psicologia , Diabetes Mellitus/patologia , Dislipidemias/patologia , Feminino , Humanos , Hipertensão/patologia , Obesidade/patologia , Percepção , Prevalência , Fatores de Risco , Singapura/epidemiologia , Fumar
5.
Nurse Pract ; 30 Suppl Sourcebook: 15-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15540047
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