• Natural Product Sciences
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• 제24권1호
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• pp.66-70
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• 2018

Helminthostachys zeylanica is a rare plant grows in lightly shaded areas. The fern was traditionally used as antipyretic and antiphlogistic agents. This study was aimed to evaluate the antibacterial potential of H. zeylanica on foodborne Bacillus cereus. The chemical composition of its ethanolic extract was also determined. The plant samples were collected at Kampung Kebun Relong, Kedah, Malaysia. The ethanolic extract showed significant inhibitory activity on B. cereus with a sizeable clear zone detected on disc diffusion assay. On broth microdilution assay, the MIC of the extract on B. cereus was 6.25 mg/ml and the MBC was 12.5 mg/ml. The inhibitory activity of the extract on B. cereus was bactericidal. In the growth dynamic study, the antibacterial efficacy of the extract was concentration dependent, where a lower colony forming unit count was obtained with increased extract concentration. The SEM micrograph of extract treated B. cereus cells showed invaginations of cell wall. The bacterial cell structure collapsed after 24 h exposure to the extract. The GCMS analysis of the extract showed that the major constituents of the extract were phenol (36.26%) and quercetin (29.70%). This study is important as it shows the potential use of H. zeylanica as an effective agent to control B. cereus related infections.

• 식물분류학회지
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• 제39권3호
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• pp.135-142
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• 2009

엽록체 rbcL gene의 염기서열과 포자의 형태를 바탕으로 고사리삼과 식물의 계통과 제주고사리삼속의 계통학적 위치를 추정하였다. 엽록체 DNA rbcL 염기서열의 분석 결과 고사리삼과는 뚜렷하게 고사리삼계보 (Botrychioid lineage)와 나도고사리삼계보 (Ophioglossoid lineage)의 두 군으로 구분되었다. 고사리삼계보에 있어 제주고사리삼속(Mankyua)은 Helmintostachys속과 함께 분계의 기저에서 고사리삼속(Botrychium)의 자매분류군으로 분지하였으나, 이들 고사리삼속(Botrychium), 제주고사리삼속(Mankyua), 및 Helmintostachys속 사이의 계통적 유연관계는 결정되지 못했다. 고사리삼속의 경우 Sceptridium아속과 Botrychium아속이 뚜렷한 단계통을 형성하였으나, Botrypus아속에 속한 분류군들은 고사리삼속의 기저에서 다른 고사리삼속 분류군의 자매분류군으로 분지하면서 단계통이 아닌 것으로 밝혀졌다. 나도고사리삼계보를 형성하는 나도고사리삼속(Ophioglossum)의 경우, Ophioglossum아속은 단계통을 형성하였으며, Ophioglossum아속에 대해 Cheiroglossa아속 및 Ophioderma 아속이 차례로 자매분류군으로 분지하였다. 염기서열 계통수, 포자의 형태 및 외부형태의 고찰에 있어 제주고사리삼속은 Helminthostachys와 유사하지만, 계통수에서 patristic distance 뿐 아니라 포자소엽의 형태가 뚜렷이 구분되어 이들 2속은 독립된 속으로 판단된다.

• 식물분류학회지
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• 제48권1호
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• pp.1-8
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• 2018

Mankyua chejuense is the only member of the monotypic genus Mankyua (Ophioglossaceae) and is endemic to Jejudo Island, Korea. To determine the precise phylogenetic position of M. chejuense, two cpDNA regions of 42 accessions representing major members of lycophytes are obtained from GenBank and analyzed using three phylogenetic analyses (maximum parsimony, maximum likelihood, and Bayesian inference). In addition, the divergence time is estimated based on a relaxed molecular clock using four fossil calibration points. The phylogenetic position of Mankyua still appears to be uncertain, representing either the earliest diverged lineage within Ophioglossaceae or a sister to the clade containing Ophioglossum and Helminthostachys. The most recent common ancestor of Ophioglossaceae and its sister lineage, Psilotum, was estimated to be 256 Ma, while the earliest divergence of Mankyua was estimated to be 195 Ma in the early Jurassic.