Novel Antifungal Dimers from the Roots of Taiwania cryptomerioides

Five new dimer compounds, namely Taiwaniacryptodimers A‒E (1–5), were isolated from the methanol extract of the roots of Taiwania cryptomerioides. Their structures were established by mean of spectroscopic analysis and comparison of NMR data with those of known analogues. Their antifungal activities were also evaluated. Our results indicated that metabolites 1, 2, 4, and 5 displayed moderate antifungal activities against Aspergillus niger, Penicillium italicum, Candida albicans, and Saccharomyces cerevisiae.

THÀNH PHẦN HÓA HỌC CỦA TINH DẦU TỪ LÁ VÀ CÀNH LOÀI BÁCH TÁN ĐÀI LOAN (TAIWANIA CRYPTOMERIOIDES HAYATA) Ở LÀO CAI

Tinh dầu từ lá và cành của loài Bách tán Đài Loan (Taiwania crypomerioides) thu mẫu tại Văn Bàn, Lào Cai, được chưng cất bằng phương pháp lôi cuốn hơi nước hồi lưu. Hàm lượng tinh dầu từ lá và cành loài Bách tán Đài Loan đạt 0,14 % và 0,18% (theo nguyên liệu khô không khí). Tinh dầu có màu vàng nhạt, nhẹ hơn nước. Bằng phương pháp sắc ký khí ghép khối phổ (GC/MS), 47 hợp chất từ tinh dầu lá loài Bách tán Đài Loan đã được xác định, những thành phần chính của tinh dầu gồm: α-pinene (36,84%), limonene (27,04%), α-terpinyl acetate (3,44%), spathulenol (3,48%) và δ-cadinene (1,83%); 44 hợp chất từ tinh dầu của cành loài Bách tán Đài Loan đã được xác định, những thành phần chính của tinh dầu gồm: α-pinene (44,24%), limonene (27,19%), α-terpinyl acetate (2,64%), spathulenol (2,58%) và epi-α-cadinol (1,34%). Đây là dẫn liệu mới về thành phần hóa học của tinh dầu lá và cành loài Bách tán Đài Loan ở Việt Nam.

Unveiling Monoterpene Biosynthesis in Taiwania cryptomerioides via Functional Characterization

Taiwania cryptomerioides is a monotypic species, and its terpenoid-rich property has been reported in recent years. To uncover monoterpene biosynthesis in T. cryptomerioides, this study used transcriptome mining to identify candidates with tentative monoterpene synthase activity. Along with the phylogenetic analysis and in vitro assay, two geraniol synthases (TcTPS13 and TcTPS14), a linalool synthase (TcTPS15), and a β-pinene synthase (TcTPS16), were functionally characterized. Via the comparison of catalytic residues, the Cys/Ser at region 1 might be crucial in determining the formation of α-pinene or β-pinene. In addition, the Cupressaceae monoterpene synthases were phylogenetically clustered together; they are unique and different from those of published conifer species. In summary, this study aimed to uncover the ambiguous monoterpenoid network in T. cryptomerioide, which would expand the landscape of monoterpene biosynthesis in Cupressaceae species.

Extractives elucidation of Taiwania cryptomerioides sapwood

Taiwania (Taiwania cryptomerioides Hayata) has long been regarded as a living fossil from the Tertiary period of Mesozoic Era for its distinguished yellowish-red color with purplish-pink streaks presented in its heartwood. With this elegant appearance that matches the color “red” for good fortune in the Taiwanese culture, Taiwania is supposed to be a popular wood in Taiwan where it is a native species of. Extractives contribute to the properties of wood. It is a fascinating subject to investigate extractives biosynthesis in the process of heartwood formation. Up to date, there is no phytochemistry study of Taiwania sapwood. In this study, three new sesquiterpenoids, Taiwania A (1), Taiwania B (2), and Taiwania C (3), together with 75 known compounds in the Taiwania sapwood. The structures of extractives were determined by analysis of spectroscopic data and comparison with the literatures. This study supported secondary reaction lignans could be found in sapwood that confirmed our previous research on the Taiwania-type of heartwood formation.

Differential Gene Profiling of the Heartwood Formation Process in Taiwania cryptomerioides Hayata Xylem Tissues

Taiwania (Taiwania cryptomerioides) is an important tree species in Taiwan because of the excellent properties of its wood and fascinating color qualities of its heartwood (HW), as well as the bioactive compounds therein. However, limited information is available as to the HW formation of this species. The objective of this research is to analyze the differentially expressed genes (DEGs) during the HW formation process from specific Taiwania xylem tissues, and to obtain genes that might be closely associated with this process. The results indicated that our analyses have captured DEGs representative to the HW formation process of Taiwania. DEGs related to the terpenoid biosynthesis pathway were all up-regulated in the transition zone (TZ) to support the biosynthesis and accumulation of terpenoids. Many DEGs related to lignin biosynthesis, and two DEGs related to pinoresinol reductase (PrR)/pinoresinol lariciresinol reductase (PLR), were up-regulated in TZ. These DEGs together are likely involved in providing the precursors for the subsequent lignan biosynthesis. Several transcription factor-, nuclease-, and protease-encoding DEGs were also highly expressed in TZ, and these DEGs might be involved in the regulation of secondary metabolite biosynthesis and the autolysis of the cellular components of ray parenchyma cells in TZ. These results provide further insights into the process of HW formation in Taiwania.