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Essential Oils and Volatiles in Bryophytes
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Agnieszka Ludwiczuk, Yoshinori Asakawa
Liverworts belonging to the genus Radula are very exceptional spore-forming plants. These produce a number of volatile bibenzyl compounds. The most characteristic are prenylated bisbibenzyls (e.g., 34). Compounds with a 2,2-dimethylchromane ring skeleton (e.g., 35) and dihydrooxepin skeleton (e.g., 36) are also prevalent (Asakawa, 1982, 1995; Asakawa et al., 2013b). 3-Methoxy bibenzyl (37) was the major EO component from R. complanata and R. lindenbergiana. Interestingly, some Radula species produce bibenzyl cannabinoids (e.g., 38). All cannabinoids isolated from Radula thus far belong to one of three types: (a) the o-cannabichromene , (b) o-cannabicyclol , and (c) tetrahydrocannabinol, with the o-cannabichromene type as the most prevalent (Asakawa et al., 2013b). The presence of radulanin H (36), a compound with a didihydrooxepin skeleton, was also confirmed in the EO of R. lindenbergiana (Figueiredo et al., 2009) (Figure 21.7). The content of terpenoids in Radula species is generally very low, but there are some exceptions; for example, R. perrottetii. From the essential oil of the Japanese collection, the presence of a huge amount of bisabola-2,6,11-triene was confirmed. From this essential oil, two viscidane diterpenoids were also isolated (Tesso et al., 2005).
Aquatic Plants Native to Asia and Australia
Published in Namrita Lall, Aquatic Plants, 2020
Marco Nuno De Canha, Danielle Twilley, B. Venugopal Reddy, SubbaRao V. Madhunapantula, N. P. Deepika, T. N. Shilpa, B. Duraiswamy, S. P. Dhanabal, Suresh M. Kumar, Namrita Lall
Axenic culture of R. natans resulted in the isolation and characterization of bibenzyl (2,5,4′-trihydroxybibenzyl), dimeric bisbibenzyl (6′,6′-bis-riccardin C), and a phenylethylcyclohexenone, prelunularin (Kunz and Becker 1994). This plant has high concentrations of luteolin 7,3′-di-O-glucuronide, and other derivatives, including the 7-O-glucuronides of apigenin and luteolin as well as the 3′-O-glucuronide of luteolin (Markham and Porter 1975). Five new sesquiterpenoids, three monocyclofarnesane derivatives, and two cuparane derivatives were isolated and reported from R. natans. Apart from these (−)-limonene, cuparene, phytol, and lunularin were also reported (Figure 3.30) (Wurzel and Becker 1990b). The plant has been reported to contain cuprenolide,cuprenolidol, ricciocarpin A, ricciocarpin, ricciofuranol, and phytol (Wurzel and Becker 1990a).
Brazilian Bryophytes and Pteridophytes as Rich Sources of Medicinal Compounds
Published in Luzia Valentina Modolo, Mary Ann Foglio, Brazilian Medicinal Plants, 2019
Adaíses Simone Maciel-Silva, Lucas Vieira Lima
Marthantiophyta exhibits a wide diversity of bis-bibenzyls (Figure 7.9), mostly among Jungermannniales, Marthantiales, and Metzgeliares. Several Marchantia species are rich sources of bis-bibenzyls; dimeric bis-bibenzyls are significant components of Riccardia species; and Radula species are rich in bibenzyls and prenyl bibenzyls. Corsinia coriandrina is unique in producing nitrogen- and sulfur-containing compounds (Asakawa et al., 2013a). Plagiochila diversifolia produces three prebibenzyls: longispinone A (36), longispinone B (37), and longispinol (38) (Heinrichs et al., 2000). Prelunularin (39) has been recorded in the thallose liverworts Marchantia polymorpha and R. natans (Kunz and Becker, 1994). Lunularin (40) and lunularic acid (41) have been identified in different thallose liverworts, including Lunularia cruciata, D. hirsuta, M. polymorpha, and R. natans (Asakawa et al., 1996; Kunz and Becker, 1994; Lu et al., 2006).
R-spondin family biology and emerging linkages to cancer
Published in Annals of Medicine, 2023
Zhimin He, Jialin Zhang, Jianzhong Ma, Lei Zhao, Xiaodong Jin, Hongbin Li
A considerable amount of research demonstrated the critical role of RSPOs in cancer. The loss of regulation of the Wnt/β-catenin signaling pathway is linked to the onset and progression of a variety of tumors. Therefore, inhibitors, antagonists, and agonists are created to treat solid tumors and hematological malignancies [53]. Porcupine inhibitors [54], Wnt/FZD antagonists [55], LRP5/6 inhibitors [56], and some targeted medicaments for the β‑catenin‑destruction complex have been developed [57,58]. Seeber et al. reported that RNF43 mutation and RSPO fusion in colon cancer were caused by dysregulated Wnt/β-catenin signaling, suggesting that changes in these genes might present new therapeutic targets [23]. In addition to the above, natural agents play a crucial role in therapy, such as gigantol, a bibenzyl compound from orchid species, which could suppress Wnt/β-catenin signaling via downregulating the expressions of phosphorylated LRP6 and cytosolic β-catenin in breast cancer cells [59]. Nimbolide, a limonoid present in neem leaves, could eliminate the canonical Wnt/β-catenin signaling and simultaneously induce the endogenous apoptosis of hepatocarcinoma cells [60].
Design, synthesis, biological evaluation and molecular docking study of 2,4-diarylimidazoles and 2,4-bis(benzyloxy)-5-arylpyrimidines as novel HSP90 N-terminal inhibitors
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2022
Man Yang, Chenyao Li, Yajing Li, Chen Cheng, Meiyun Shi, Lei Yin, Hongyu Xue, Yajun Liu
We previously reported that a series of 1,3-dibenzyl-2-aryl imidazolidines 8 served as HSP90 N-terminal inhibitors27 (Figure 2). These inhibitors showed a strong affinity for the HSP90 N-terminus according to the fluorescence polarisation (FP) assay; however, they exhibited weak antiproliferative activity against cancer cells such as MCF-7 and A549. Weak anticancer efficacy may be attributed to the physicochemical instability of the imidazolidine ring because 8 is converted into the corresponding benzaldehyde and N, N’-dibenzyl ethylenediamine in an aqueous medium28–30. Therefore, we hypothesised that replacing imidazolidine with stable aromatic scaffolds would lead to the discovery of novel HSP90 N-terminal inhibitors with stronger anticancer activity. Therefore, the nonaromatic imidazolidine ring was replaced by the aromatic imidazole ring and pyrimidine ring, which are frequently used in clinical drugs31,32. As shown in Figure 2, trisubstituted imidazole 9 and pyrimidine 10 were designed to develop novel HSP90 inhibitors. Compound 9 bears a benzyl group at the N1 position and two phenyl groups at the C2 and C4 positions of the imidazole ring. In the case of 10, it has two benzyloxy groups at the C2 and C4 positions and a phenyl group at the C5 position of the pyrimidine ring.
Chitosan-coated bovine serum albumin nanoparticles for topical tetrandrine delivery in glaucoma: in vitro and in vivo assessment
Published in Drug Delivery, 2022
Salma El-Sayed Radwan, Riham M. El-Moslemany, Radwa A. Mehanna, Eman H. Thabet, Elsayeda-Zeinab A. Abdelfattah, Amal El-Kamel
In vitro release profiles of TET from TET suspension, TET-BSA-NPs and CS-TET-BSA-NPs are shown in Figure 2. TET suspension showed 35.6 ± 0.65% release after 2 h and reached 60 ± 0.23% after 6 h. By the end of the experiment, 71.63 ± 0.59% TET was released. Li et al. (2020) reported that as TET is a dibenzyl isoquinoline alkaloid, its solubility is affected by the solution’s pH. TET solubility was lower at pH 7.4 compared to pH 6. This possibly explains why TET was not 100% released in the current experiment. Nevertheless, PBS pH 7.4 was chosen for the comparative in vitro release study as it mimics the ocular pH. TET loading into BSA-NPs resulted in a sustained drug release with a highly significant decrease in drug burst (19.65 ± 0.23% at 2 h) compared to TET suspension (35.6 ± 0.65%) reaching a maximum of 57.3% after 48 h. CS coating of BSA-NPs resulted in a further significant reduction in drug release with only 12.38 ± 0.02% burst. Despite the significantly slower release (p ≤ .05) of TET from CS-coated formulation compared to the uncoated one in early time samples; up to 6 h, this difference disappeared later on probably due to the hydration and swelling of CS coat by time as previously reported (Raj et al., 2018; Piazzini et al., 2019).