• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.581-589
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• 2021

Using visible-near infrared(Vis-NIR) spectra combined with machine learning methods, the feasibility of quick and non-destructive classification of Convolvulaceae species was studied. The main aim of this study is to classify six Convolvulaceae species in the field in different geographical regions of South Korea using a handheld spectrometer. Spectra were taken at 1.5 nm intervals from the adaxial side of the leaves in the Vis-NIR spectral region between 400 and 1,075 nm. The obtained spectra were preprocessed with three different preprocessing methods to find the best preprocessing approach with the highest classification accuracy. Preprocessed spectra of the six Convolvulaceae sp. were provided as input for the machine learning analysis. After cross-validation, the classification accuracy of various combinations of preprocessing and modeling ranged between 43.4% and 98.6%. The combination of Savitzky-Golay and Support vector machine methods showed the highest classification accuracy of 98.6% for the discrimination of Convolvulaceae sp. The growth stage of the plants, different measuring locations, and the scanning position of leaves on the plant were some of the crucial factors that affected the outcomes in this investigation. We conclude that Vis-NIR spectroscopy, coupled with suitable preprocessing and machine learning approaches, can be used in the field to effectively discriminate Convolvulaceae sp. for effective weed monitoring and management.

• Korean Journal of Plant Taxonomy
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• v.53 no.1
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• pp.60-64
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• 2023

Ipomoea cristulata Hallier f. (Convolvulaceae), native to the desert regions of the central USA to Mexico, was newly found in Gojeong-ri, Deokgwa-myeon, Namwon-si, Jeollabuk-do. This species can be distinguished from I. coccinea by leaves with 3-5 lobes, hirsute distributed adaxially, and corolla entirely red or orange-red. Its Korean name is 'Nabi-ip-yu-hong-cho' based on its butterfly-shaped leaves. We provide a detailed description, photographs, habitat details, and a taxonomic key to related taxa.

• Korean Journal of Plant Taxonomy
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• v.50 no.3
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• pp.351-355
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• 2020

Argyreia gyrobracteata Traiperm & Chitchak (Convolvulaceae) is newly recorded in Vietnam. It is similar to A. mekongensis Gagnep & Courch in having a white campanulate corolla but differs from that species by having whitish surface of the abaxial leaf, narrowly lanceolate or linear-oblong, curly, rolled up the bract with a longer length of the petiole and a shorter pedicel. It was previously known only in Thailand, but was recently found in Lam Dong Province, Vietnam, for the first time. The present study provides a detailed description, colorful photos and the distribution of the species. Furthermore, a comparison of the diagnostic characters between this species and a related species in Vietnam, A. mekongensis Gagnep & Courch, is provided.

• Natural Product Sciences
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• v.13 no.4
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• pp.273-278
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• 2007

This paper presents a detailed pharmacognostical study of the stem and root of the crude drug Ipomoea quamoclit Linn. (Convolvulaceae). Morphoanatomy of the stem and root have been studied with the aim to aid pharmacognostic and taxonomic species identification using light and confocal microscopy, WHO recommended physico-chemical determinations and authentic phytochemical procedures. The physico-chemical, morphological and histological parameters presented in this paper may be proposed as parameters to establish the authenticity of stem and root of I. quamoclit and may possibly help to differentiate the drug from its other species.

• Korean Journal of Pharmacognosy
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• v.13 no.2
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• pp.62-69
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• 1982

Fiftythree species(35 families and 52 genera)of Korean medicinal plants which have been frequently used in oriental herb prescriptions or have been used as folklorics were evaluated on their short term acute toxicity and potential antitumor activities against P-388 murine lymphocytic leukemia model in vivo. Among these plants Acorus gramineus (Araceae), Agrimonia pilosa (Rosaceae), Aralia elata (Araliaceae), Dryopteris crassirhizoma (Aspidiaceae), Syringa reticulata (Oleaceae) and Calystegia japonica (Convolvulaceae) exhibited potent acute toxicity resulting from severe weight loss and death. Agrimonia pilosa (Rosaceae) showed about 33% of increased life span in comparison with that of control group mouse, but others exhibited no significant antitumor activities.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.368.3-369
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• 2002

Pharbitis nil Choisy (convolvulaceae) is an annual vine plant and grows at the wayside of Korea. Japan. China and India. The seeds of blue or red Pharbitis nil Choisy. Pharbitidis Semen, is black or red-brown. This seeds have been used as a purgative. From a preliminary experiment. Pharbitidis Semen exhibited anti-cancer activity. MeOH extract of this seeds was subsequently fractionated into four parts: methylene chloride, ethylacetate, n-butanol and water fractions. (omitted)

• Natural Product Sciences
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• v.6 no.3
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• pp.135-138
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• 2000

MeOH extract of Cuscuta chinensis seeds was fractionated with n-hexane, EtOAc and BuOH successively, and antioxidant activities were tested for all fractions using DPPH free radical scavenging method. In the tested fractions, EtOAc fraction showed high antioxidant activity$(EC_{50},\;50\;{\mu}g)$ From the EtOAc fraction, five compounds have been isolated. On the basis of spectral data, these compounds were identified as ${\beta}-sitosterol$, methyl 4-hydroxy-3,5-dimethoxycinnamate, ${\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside$, caffeic acid, quercetin, kaempferol and calycopteretin. Among these compounds, ${\beta}-sitosterol$ and ${\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside$ showed no antioxidant activity. $EC_{50}$ values of methyl 4-hydroxy-3,5-dimethoxycinnamate, caffeic acid, quercetin, kaempferol and calycopteretin were 0.6, 8, 19, 17 and $12\;{\mu}g$, respectively.

• Journal of Plant Biology
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• v.35 no.2
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• pp.173-182
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• 1992

The parasitic flowering plants obtain nutrients and water from their host plants through a parasitic organ, haustorium, which connects both structurally and physiologically host and parasite. The parasitism in angiosperms thus can be understood from the knowledge of the haustorial structure. The haustoria have evolve convergently and independently in several unrelated taxa; therefore, they have similar morphology. Many anatomical studies on the haustoria in several parasites in the pst have been carried out by light microscopy. Ultrastructural studies on the haustoria, which are started from the end of 1060s', have provided new information relating to the phenomenon of parasitism in angiosperms. The purpose of this paper is to introduce and compare the structure of haustoria between parasitic plants. The results may help an understanding of phylogenetic relationships of parasitic angiosperms. The haustoria of some families, such as Santalaceae, Orobancaceae, Scrophulariaceae, Loranthaceae (or Viscaceae), and Convolvulaceae (Cuscuta) will be discussed.

• Natural Product Sciences
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• v.5 no.3
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• pp.124-126
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• 1999

A new natural product $stigmast-5-en-3-O-{\beta}-D-glucopyranoside$ tetraacetate (1) along with known compounds $stigmast-5-en-3-O-{\beta}-D-glucopyranoside$ (2), stigmast-5-en-3-yl-cetate (3) and ${\beta}-sitosterol$ (4) have been isolated from the stems of Cuscuta reflexa. Their structures were elucidated on the basis of chemical and spectroscopic evidence.

• The Korean Journal of Mycology
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• v.50 no.1
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• pp.55-59
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• 2022

Anamorph of a powdery mildew was collected from Convolvulus arvensis (Convolvulaceae) in 2021 in Korea. Based on the morphological examination and molecular phylogenetic analyses of the internal transcribed spacer and large subunit rDNA gene, the powdery mildew was identified as Erysiphe convolvuli. This powdery mildew species is commonly found in Europe and North America, but rarely in East Asia. The holomorph of this powdery mildew was first recorded on Calystegia hederacea in Korea. Conclusively, this is the first report of E. convolvuli on C. arvensis and the second record of this powdery mildew species in Korea.