Thotneosides A, B and C: Potent Antioxidants from Nepalese Crude Drug, Leaves of &lt;i&gt;Aconogonon molle&lt;/i&gt;

Joshi, Khem Raj; Devkota, Hari Prasad; Watanabe, Takashi; Yahara, Shoji

doi:10.1248/cpb.c13-00748

Cited by 8 publications

(5 citation statements)

References 10 publications

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“…70% MeOH was used for extraction due to its ability to partition a wide range of polarities and soluble phenolic compounds such as phenolic glycosides, flavonoids, phenolic acids, lignans, xanthones, coumarins, iridoids, chalcones, and terpenoids [ 9 , 10 , 14 , 20 ]. The high yield of the A. helferiana rhizome extract could be due to the high content of polar and 70% methanol-soluble components (polyphenols, flavones, and carbohydrates) in the A. helferiana rhizome.…”

Section: Discussionmentioning

confidence: 99%

Antioxidant and Antibacterial Activities Evaluation, Phytochemical Characterisation of Rhizome from Angiopteris helferiana and Barks from Saurauia fasciculata in Nepal

Yadav,

Dhakal,

Timilsina

et al. 2024

The Scientific World Journal

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Ethnomedicinally, more than 2000 plants were found to be used in Nepal. Among them, the red colored rhizome of Angiopteris helferiana and the bark of Saurauia fasciculata have been used widely to treat muscle fatigue, bone pain, fever, postpartum hemorrhage, and thirst by healers in Kaski and Tanahun districts, Nepal. However, scientific evidence towards their traditional uses is lacking till December, 2023. Therefore, we report the phytochemicals, total phenolic content (TPC), total flavonoid content (TFC), total carbohydrate content (TCC), antioxidant and antibacterial activities of A. helferiana and S. fasciculata extracts. Phytochemical analysis indicated that A. helferiana and S. fasciculata extracts were potential sources of chemicals such as phenols, flavonoids, tannins, terpenoids, saponins, and carbohydrates. The TPC, TFC, and TCC of extracts were determined by using an ultraviolet visible spectrophotometer. Among the extracts tested, A. helferiana extracts showed the highest phenolic and carbohydrate contents of 208.33 ± 12.96 mg of gallic acid equivalent/g and 564.16 ± 2.92 mg of D‐glucose equivalent/g of dry extract, respectively. Similarly, S. fasciculata revealed the highest flavonoid content of 30.35 ± 0.1 mg quercetin equivalent/g of dry extract. The extract of A. helferiana and S. fasciculata exhibited potent antioxidant activity by scavenging 2,2‐diphenyl‐1‐picrylhydrazyl radicals with an IC50 of 25.9 µg/ml and 31.07 µg/ml, respectively. The antibacterial activity of the A. helferiana and S. fasciculata extract against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli was determined using an agar‐well diffusion protocol that revealed the potential antibacterial activity of A. helferiana against E. coli. The present study will help validate the traditional uses of A. helferiana rhizomes and S. fasciculata barks as a healing medicine and inspire the researcher towards further research, development, and formulation.

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Section: Discussionmentioning

confidence: 99%

Antioxidant and Antibacterial Activities Evaluation, Phytochemical Characterisation of Rhizome from Angiopteris helferiana and Barks from Saurauia fasciculata in Nepal

Yadav,

Dhakal,

Timilsina

et al. 2024

The Scientific World Journal

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“…FeCl 3 and 10% H 2 SO 4 as spraying agent. Comparable solvent ratios and spraying agents in similar concentrations were employed in reference with various literature addressing chemical isolation and TLC profiling (Joshi et al, 2014;Sai et al, 2020). The entire assignment of the proton and carbon atoms, their location and linkage with anomeric protons were determined and compared with chemical shift values of related similar compounds on the literature (Joshi et al, 2013;Thoa et al, 2019;Wen et al, 2017).…”

Section: Structure Elucida Onmentioning

confidence: 99%

Phytochemical Analysis and Bioactivity of Nepalese Medicinal Plants, with Compound Isolation from Dischidia bengalensis Colebr.

Gurung,

Sharma,

Gurung

et al. 2024

NRFHH

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Numerous medicinal plants have been used traditionally to treat, relieve, and prevent various diseases since ancient time, yet many of them are to be scientifically investigated. The present study was carried out with the aim of phytochemical screening, determination of 1,1–diphenyl–2–picrylhydrazyl (DPPH) free radical scavenging activity and antibacterial activity of 70% methanolic extracts of six medicinal plants of Nepal used by different ethnic tribes, and to isolate chemical compounds from one of them. Agar well diffusion method was used to assess the in vitro antibacterial activity, whereas the chemical isolation was carried out using different chromatographic techniques. Then, the structure of the isolated compounds was determined by using NMR (Nuclear Magnetic Resonance) spectroscopic method, followed by spectral analysis in comparison with published data. Of the six extracts, the extracts of Angiopteris helferiana and Drynaria coronans showed moderate antibacterial activities. Moreover, the extract of Dischidia bengalensis showed the most potent antioxidant activity and was thus subjected to chromatographic separations utilizing different chromatographic principles to isolate 2"-O- rhamnosylvitexin (1) and isovitexin (2). These secondary metabolites are reported for the first time from this plant whilst, their pharmacological activity is yet to be screened.

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“…Narural glycosides such as thotneoside C (5), 39 tecomin ( 6) 40 (gram-scale synthesis), perilloside B (7) 41 , and skimmin (9) 42 were obtained from α-D-glucose and commercially available reagents in one-step under Mitsunobu conditions. β-Glucogallin (8) 43 was prepared in 67% yield in two steps from α-D-glucose.…”

Section: Table 1 Scope Of Glycosyl Donors In Sn2-type Glycosylationmentioning

confidence: 99%

SN2-Type Glycosylation with Unprotected Pyranoses

Takeuchi¹,

Fujimori²,

Shibayama³

et al. 2019

Preprint

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An SN2 mechanism was proposed for highly stereoselective glycosylation of benzoic acid with unprotected α-D-glucose under Mitsunobu conditions in dioxane, while an SN1 mechanism seems to be responsible for non-stereoselective glycosylation in DMF. The SN2-type glycosylation can be applicable to various unprotected pyranoses as glycosyl donors and a wide range of carboxylic acids, phenols, and imides as glycosyl acceptors, retaining its high stereoselectivity (34 examples). Glycosylation of a carboxylic acid with unprotected α-D-mannose proceeded also in an SN2 manner to directly afford a usually less accessible 1,2-cis-mannoside. An extremely short-step total synthesis of a middle molecule (1874 Da) natural glycoside with antitumor activity, coriariin A, was achieved via a double SN2 glycosylation strategy with two molecules of unprotected α-D-glucose.

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Thotneosides A, B and C: Potent Antioxidants from Nepalese Crude Drug, Leaves of <i>Aconogonon molle</i>

Cited by 8 publications

References 10 publications

Antioxidant and Antibacterial Activities Evaluation, Phytochemical Characterisation of Rhizome from Angiopteris helferiana and Barks from Saurauia fasciculata in Nepal

Antioxidant and Antibacterial Activities Evaluation, Phytochemical Characterisation of Rhizome from Angiopteris helferiana and Barks from Saurauia fasciculata in Nepal

Phytochemical Analysis and Bioactivity of Nepalese Medicinal Plants, with Compound Isolation from <i>Dischidia bengalensis</i> Colebr.

SN2-Type Glycosylation with Unprotected Pyranoses

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