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Venalstonine and dioxokopsan derivatives from Kopsia fruticosa

Kam TS, Choo YM

Phytochemistry, 2004 Jul;65(14):2119-22.

Two new venalstonine derivatives, viz., venacarpines A and B, and one new dioxokopsan derivative, kopsorinine, in addition to the kopsifolines A-F, and 11 other known alkaloids, were isolated from a Malayan Kopsia species. The structures of the new alkaloids were determined using NMR and MS analysis.

Matched MeSH terms: Alkaloids/isolation & purification*

New indole alkaloids from Alstonia macrophylla

Kam TS, Choo YM

J Nat Prod, 2004 Apr;67(4):547-52.

PMID: 15104482

Ten new indole alkaloids, alstomaline (1), 10,11-dimethoxynareline (2), alstohentine (3), alstomicine (4), 16-hydroxyalstonisine (5), 16-hydroxyalstonal (6), 16-hydroxy-N(4)-demethylalstophyllal oxindole (7), alstophyllal (8), 6-oxoalstophylline (9), and 6-oxoalstophyllal (10), in addition to 21 other known ones, were obtained from the leaf extract of the Malayan Alstonia macrophylla. The structures were determined using NMR and MS analysis.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Alkaloids from Alstonia angustifolia

Kam TS, Choo YM

Phytochemistry, 2004 Mar;65(5):603-8.

PMID: 15003424

Six new alkaloids, viz., alstolactone, affinisine oxindole, lagumicine, N(4)-demethylalstonerine, N(4)-demethylalstonerinal, and 10-methoxycathafoline N(4)-oxide, in addition to 36 other known alkaloids, were obtained from the leaf extract of Alstonia angustifolia var. latifolia. The structures of the new alkaloids were determined using NMR and MS analysis.

Matched MeSH terms: Alkaloids/isolation & purification

Neolamarckines A and B, new indole alkaloids from Neolamarckia cadamba

Qureshi AK, Mukhtar MR, Hirasawa Y, Hosoya T, Nugroho AE, Morita H, et al.

Chem Pharm Bull (Tokyo), 2011;59(2):291-3.

PMID: 21297315

Two new indole alkaloids, neolamarckines A and B (1, 2) were isolated from the leaves of Neolamarckia cadamba (Rubiaceae). Structural elucidation of 1 and 2 was performed by combination of 2D-NMR and circular dichroism (CD) spectra, and chemical correlations. Neolamarckine A (1) showed inhibition of inducible nitric oxide synthase (iNOS) dose dependently.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Fulltext Accelerated Solvent Extractions (ASE) of Mitragyna speciosa Korth. (Kratom) Leaves: Evaluation of Its Cytotoxicity and Antinociceptive Activity

Goh YS, Karunakaran T, Murugaiyah V, Santhanam R, Abu Bakar MH, Ramanathan S

Molecules, 2021 Jun 17;26(12).

PMID: 34204457 DOI: 10.3390/molecules26123704

Mitragyna speciosa Korth (kratom) is known for its psychoactive and analgesic properties. Mitragynine is the primary constituent present in kratom leaves. This study highlights the utilisation of the green accelerated solvent extraction technique to produce a better, non-toxic and antinociceptive active botanical extract of kratom. ASE M. speciosa extract had a dry yield (0.53-2.91 g) and showed a constant mitragynine content (6.53-7.19%) when extracted with organic solvents of different polarities. It only requires a shorter extraction time (5 min) and a reduced amount of solvents (less than 100 mL). A substantial amount of total phenolic (407.83 ± 2.50 GAE mg/g and flavonoids (194.00 ± 5.00 QE mg/g) were found in ASE kratom ethanol extract. The MTT test indicated that the ASE kratom ethanolic leaf extract is non-cytotoxic towards HEK-293 and HeLa Chang liver cells. In mice, ASE kratom ethanolic extract (200 mg/kg) demonstrated a better antinociceptive effect compared to methanol and ethyl acetate leaf extracts. The presence of bioactive indole alkaloids and flavonols such as mitragynine, paynantheine, quercetin, and rutin in ASE kratom ethanolic leaf extract was detected using UHPLC-ESI-QTOF-MS/MS analysis supports its antinociceptive properties. ASE ethanolic leaf extract offers a better, safe, and cost-effective choice of test botanical extract for further preclinical studies.

Matched MeSH terms: Secologanin Tryptamine Alkaloids/isolation & purification*

Selective dual cholinesterase inhibitors from Aconitum laeve

Ahmad H, Ahmad S, Shah SAA, Khan HU, Khan FA, Ali M, et al.

J Asian Nat Prod Res, 2018 Feb;20(2):172-181.

PMID: 28463565 DOI: 10.1080/10286020.2017.1319820

New lycoctonine-type dual cholinesterase inhibitor, swatinine-C (1), along with three known norditerpenoid alkaloids, hohenackerine (2), aconorine (5) and lappaconitine (6) and two synthetically known but phytochemically new benzene derivatives, methyl 2-acetamidobenzoate (3) and methyl 4-[2-(methoxycarbonyl)anilino]-4-oxobutanoate (4), was isolated from the roots of A. laeve. Structures of new and known compounds (1-6) were established on the basis of latest spectroscopic techniques and by close comparison with the data available in literature. In vitro, compounds (1-6) were tested against AChE and BChE inhibitory activities. Compounds 1 and 2 showed competitive inhibition against AChE (IC50 = 3.7 μM, 4.53 μM) and BChE (IC50 = 12.23 μM, 9.94 μM), respectively. Compounds 5 and 6 showed promising noncompetitive type of inhibitory profile against AChE (IC50 = 2.51 and 6.13 μM) only. Compounds 3 and 4 showed weak inhibitory profile against both AChE and BChE.

Matched MeSH terms: Alkaloids/isolation & purification

Leucophyllinines A and B, bisindole alkaloids from Leuconotis eugeniifolia

Tang Y, Nugroho AE, Hirasawa Y, Tougan T, Horii T, Hadi AHA, et al.

J Nat Med, 2019 Jun;73(3):533-540.

PMID: 30911994 DOI: 10.1007/s11418-019-01297-5

Two new bisindole alkaloids, leucophyllinines A (1) and B (2) consisting of eburnane and quebrachamine-type skeletons were isolated from the bark of Leuconotis eugeniifolia, and their structures were elucidated on the basis of spectroscopic data. Leucophyllinines A and B showed antiplasmodial activities against Plasmodium falciparum 3D7.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Biologically active ibogan and vallesamine derivatives from Tabernaemontana divaricata

Kam TS, Pang HS, Choo YM, Komiyama K

Chem Biodivers, 2004 Apr;1(4):646-56.

PMID: 17191876

Six new indole alkaloids, viz., (3S)-3-cyanocoronaridine (2), (3S)-3-cyanoisovoacangine (3), conolobine A (5), conolobine B (6), conolidine (7), and (3R/3S)-3-ethoxyvoacangine (8), in addition to 36 known ones, were obtained from the stem-bark extract of the Malayan Tabernaemontana divaricata. The structures were determined by NMR and MS analysis. The CN-substituted alkaloids showed appreciable cytotoxicity towards the KB human oral epidermoid carcinoma cell-line.

Matched MeSH terms: Indole Alkaloids/isolation & purification

Alkaloids from leaves and stem bark of Ervatamia corymbosa

Zèches M, Mesbah K, Loukaci A, Richard B, Schaller H, Sévenet T, et al.

Planta Med, 1995 Feb;61(1):97.

PMID: 7701009

Matched MeSH terms: Alkaloids/isolation & purification*

Biosynthetic Enantiodivergence in the Eburnane Alkaloids from Kopsia

Chong KW, Yeap JS, Lim SH, Weber JF, Low YY, Kam TS

J Nat Prod, 2017 11 22;80(11):3014-3024.

PMID: 29087707 DOI: 10.1021/acs.jnatprod.7b00621

Reexamination of the absolute configuration of recently isolated eburnane alkaloids from Malaysian Kopsia and Leuconotis species by X-ray diffraction analysis and ECD/TDDFT has revealed the existence of biosynthetic enantiodivergence. Three different scenarios are discerned with respect to the composition of the enantiomeric eburnane alkaloids in these plants: first, where the new eburnane congeners possess the same C-20, C-21 absolute configurations as the common eburnane alkaloids (eburnamonine, eburnamine, isoeburnamine, eburnamenine) occurring in the same plant; second, where the new eburnane congeners possess opposite or enantiomeric C-20, C-21 absolute configurations compared to the common eburnane alkaloids found in the same plant; and, third, where the four common eburnane alkaloids were isolated as racemic or scalemic mixtures, while the new eburnane congeners were isolated as pure enantiomers with a common C-20, C-21 configuration (20α, 21α). Additionally, the same Kopsia species (K. pauciflora) found in two different geographical locations (Peninsular Malaysia and Malaysian Borneo) showed different patterns in the composition of the enantiomeric eburnane alkaloids. Revision of the absolute configurations of a number of new eburnane congeners (previously assigned based on the assumption of a common biogenetic origin to that of the known eburnane alkaloids co-occurring in the same plant) is required based on the present results.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Fulltext Anticholinesterase inhibitory activity of quaternary alkaloids from Tinospora crispa

Yusoff M, Hamid H, Houghton P

Molecules, 2014 Jan 20;19(1):1201-11.

PMID: 24448061 DOI: 10.3390/molecules19011201

Quaternary alkaloids are the major alkaloids isolated from Tinospora species. A previous study pointed to the necessary presence of quaternary nitrogens for strong acetylcholinesterase (AChE) inhibitory activity in such alkaloids. Repeated column chromatography of the vine of Tinospora crispa extract led to the isolation of one new protoberberine alkaloid, 4,13-dihydroxy-2,8,9-trimethoxydibenzo[a,g]quinolizinium (1), along with six known alkaloids-dihydrodiscretamine (2), columbamine (3), magnoflorine (4), N-formylannonaine (5), N-formylnornuciferine (6), and N-trans-feruloyltyramine (7). The seven compounds were isolated and structurally elucidated by spectroscopic analysis. Two known alkaloids, namely, dihydrodiscretamine and columbamine are reported for the first time for this plant. The compounds were tested for AChE inhibitory activity using Ellman's method. In the AChE inhibition assay, only columbamine (3) showed strong activity with IC50 48.1 µM. The structure-activity relationships derived from these results suggest that the quaternary nitrogen in the skeleton has some effect, but that a high degree of methoxylation is more important for acetylcholinesterase inhibition.

Matched MeSH terms: Berberine Alkaloids/isolation & purification

Angustilobine and andranginine type indole alkaloids and an uleine-secovallesamine bisindole alkaloid from Alstonia angustiloba

Ku WF, Tan SJ, Low YY, Komiyama K, Kam TS

Phytochemistry, 2011 Dec;72(17):2212-8.

PMID: 21889176 DOI: 10.1016/j.phytochem.2011.08.001

A total of 20 alkaloids were isolated from the leaf and stem-bark extracts of Alstonia angustiloba, of which two are hitherto unknown. One is an alkaloid of the angustilobine type (angustilobine C), while the other is a bisindole alkaloid angustiphylline, derived from the union of uleine and secovallesamine moieties. The structures of these alkaloids were established using NMR and MS analysis. Angustilobine C showed moderate cytotoxicity towards KB cells.

Matched MeSH terms: Alkaloids/isolation & purification; Indole Alkaloids/isolation & purification*

Alkaloid extracts of Ficus species and palm oil-derived tocotrienols synergistically inhibit proliferation of human cancer cells

Abubakar IB, Lim KH, Loh HS

Nat Prod Res, 2015;29(22):2137-40.

PMID: 25515603 DOI: 10.1080/14786419.2014.991927

Tocotrienols have been reported to possess anticancer effects other than anti-inflammatory and antioxidant activities. This study explored the potential synergism of antiproliferative effects induced by individual alkaloid extracts of Ficus fistulosa, Ficus hispida and Ficus schwarzii combined with δ- and γ-tocotrienols against human brain glioblastoma (U87MG), lung adenocarcinoma (A549) and colorectal adenocarcinoma (HT-29) cells. Cell viability and morphological results demonstrated that extracts containing a mixture of alkaloids from the leaves and bark of F. schwarzii inhibited the proliferation of HT-29 cells, whereas the alkaloid extracts of F. fistulosa inhibited the proliferation of both U87MG and HT-29 cells and showed synergism in combined treatments with either δ- or γ-tocotrienol resulting in 2.2-34.7 fold of reduction in IC50 values of tocotrienols. The observed apoptotic cell characteristics in conjunction with the synergistic antiproliferative effects of Ficus species-derived alkaloids and tocotrienols assuredly warrant future investigations towards the development of a value-added chemotherapeutic regimen against cancers.

Matched MeSH terms: Alkaloids/isolation & purification

Fulltext Naucline, a new indole alkaloid from the bark of Nauclea officinalis

Liew SY, Mukhtar MR, Hadi AH, Awang K, Mustafa MR, Zaima K, et al.

Molecules, 2012 Apr 02;17(4):4028-36.

PMID: 22469596 DOI: 10.3390/molecules17044028

A new indole alkaloid, naucline (1) together with four known alkaloids, angustine (2), angustidine (3), nauclefine (4) and naucletine (5), were isolated from the bark of Nauclea officinalis. The structures of all isolated compounds were elucidated with various spectroscopic methods such as 1D- and 2D- NMR, IR, UV and LCMS-IT-TOF. In addition to that of alkaloid 1, the complete 13C-NMR data of naucletine (5) were also reported. Naucline (1) showed a moderate vasorelaxant activity (90% relaxation at 1 × 10(-5) M) whereas, angustine (2), nauclefine (4), and naucletine (5) showed potent vasorelaxant activity (more than 90% relaxation at 1 × 10(-5) M) on an isolated rat aorta.

Matched MeSH terms: Indole Alkaloids/isolation & purification

Grandilodines A-C, biologically active indole alkaloids from Kopsia grandifolia

Yap WS, Gan CY, Low YY, Choo YM, Etoh T, Hayashi M, et al.

J Nat Prod, 2011 May 27;74(5):1309-12.

PMID: 21428274 DOI: 10.1021/np200008g

Three new indole alkaloids (1-3), named grandilodines A-C, and five known ones were obtained from the Malayan Kopsia grandifolia. The structures were established using NMR and MS analyses and, in the case of 1 and 2, were confirmed by X-ray diffraction analyses. Alkaloids 1, 3, and lapidilectine B (8) were found to reverse multidrug resistance in vincristine-resistant KB cells.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

UAE, MAE, SFE-CO2 and classical methods for the extraction of Mitragyna speciosa leaves

Orio L, Alexandru L, Cravotto G, Mantegna S, Barge A

Ultrason Sonochem, 2012 May;19(3):591-5.

PMID: 22054912 DOI: 10.1016/j.ultsonch.2011.10.001

Mitragyna speciosa, a tropical plant indigenous to Southeast Asia, is well known for its psychoactive properties. Its leaves are traditionally chewed by Thai and Malaysian farmers and manual labourers as it causes a numbing, stimulating effect. The present study aims to evaluate alkaloid yield and composition in the leaf extracts. For this purpose we have compared several non-conventional extraction techniques with classic procedures (room temperature or under heating). Dried M. speciosa leaves belonging to three batches of different origin (from Thailand, Malaysia and Indonesia) were extracted using ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and supercritical carbon dioxide extraction SFE-CO(2), using methanol, ethanol, water and binary mixtures. The extracts were compared using an HPLC/ESI-MS analysis of mitragynine and four other related alkaloids which were present in the alkaloid fraction. The extraction technique influences both the raw product yield and the relative alkaloid content of M. speciosa leaves. Of the several methods tested, MAE in a closed vessel at 110 °C (60 W, methanol/water 1:1) gave the highest alkaloid fraction amount, while UAE with an immersion horn at 25 °C (21.4 kHz, 50 W, methanol) showed the best yield for mitragynine. This work may prove to be a useful contribution to forensic, toxicological and pharmacognosy studies. Although the potential applications of M. speciosa alkaloids clearly need further investigation, these results may facilitate the scaling-up of their extraction.

Matched MeSH terms: Alkaloids/isolation & purification*

Aspidospermatan-aspidospermatan and eburnane-sarpagine bisindole alkaloids from Leuconotis

Gan CY, Low YY, Robinson WT, Komiyama K, Kam TS

Phytochemistry, 2010 Aug;71(11-12):1365-70.

PMID: 20542302 DOI: 10.1016/j.phytochem.2010.05.015

Leucofoline and leuconoline, representing the first members of the aspidospermatan-aspidospermatan and eburnane-sarpagine subclasses of the bisindole alkaloids, respectively, were isolated from the Malayan Leuconotis griffithii. The structures of these bisindole alkaloids were established using NMR and MS analysis, and in the case of leuconoline, confirmed by X-ray diffraction analysis. Both alkaloids showed weak cytotoxicity towards human KB cells.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Strychnan and secoangustilobine A type alkaloids from Alstonia spatulata. Revision of the C-20 configuration of scholaricine

Tan SJ, Low YY, Choo YM, Abdullah Z, Etoh T, Hayashi M, et al.

J Nat Prod, 2010 Nov 29;73(11):1891-7.

PMID: 21043460 DOI: 10.1021/np100552b

A total of 25 alkaloids were isolated from the leaf and stem-bark extracts of Alstonia spatulata, of which five are new alkaloids of the strychnan type (alstolucines A-E, 1-5) and the other, a new alkaloid of the secoangustilobine A type (alstolobine A, 6). The structures of these alkaloids were established using NMR and MS analysis and, in the case of alstolucine B (2), also confirmed by X-ray diffraction analysis. A reinvestigation of the stereochemical assignment of scholaricine (13) by NMR and X-ray analyses indicated that the configuration at C-20 required revision. Alkaloids 1, 2, 6, 7, 9, 10, and 13 reversed multidrug resistance in vincristine-resistant KB cells.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

Effects of mitragynine from Mitragyna speciosa Korth leaves on working memory

Apryani E, Hidayat MT, Moklas MA, Fakurazi S, Idayu NF

J Ethnopharmacol, 2010 Jun 16;129(3):357-60.

PMID: 20371280 DOI: 10.1016/j.jep.2010.03.036

AIM OF THE STUDY: Mitragyna speciosa Korth from Rubiaceae family is a tropical plant indigenous to Southeast Asia particularly in Thailand, Peninsular of Malaysia and Indonesia. The leaves have been used by natives for their opium-like effect and cocaine-like stimulant ability to combat fatigue and enhance tolerance to hard work. However there is no scientific information about the effect of mitragynine on the cognitive performances. This study is designed to examine the working memory effects of mitragynine which is extracted from Mitragyna speciosa mature leaves.

MATERIALS AND METHODS: The cognitive effect was studied using object location task and the motor activity in open-field test. Mitragynine 5, 10 and 15 mg/kg and were administered by intraperitoneal (IP) for 28 consecutive days and evaluated on day 28 after the last dose treatment. Scopolamine was used as the control positive drug.

RESULTS: In this study there is prominent effects on horizontal locomotor activity was observed. Mitragynine significantly reduced locomotor activity in open-field test compared with vehicle. In object location task mitragynine (5, 10 and 15 mg/kg) did not showed any significances discrimination between the object that had changed position than the object that had remain in a constant position.

CONCLUSION: Our results suggest that chronic administration of mitragynine can altered the cognitive behavioral function in mice.

Matched MeSH terms: Secologanin Tryptamine Alkaloids/isolation & purification

Leucoridines A-D, cytotoxic Strychnos-Strychnos bisindole alkaloids from Leuconotis

Gan CY, Etoh T, Hayashi M, Komiyama K, Kam TS

J Nat Prod, 2010 Jun 25;73(6):1107-11.

PMID: 20515042 DOI: 10.1021/np1001187

Four new bisindole alkaloids of the Strychnos-Strychnos type, leucoridines A-D (1-4), were isolated from the stem-bark extract of Leuconotis griffithii. Alkaloids 1-4 showed moderate cytotoxicity against drug-sensitive and vincristine-resistant human KB cells.

Matched MeSH terms: Indole Alkaloids/isolation & purification*

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