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Biologically active vallesamine, strychnan, and rhazinilam alkaloids from Alstonia: Pneumatophorine, a nor-secovallesamine with unusual incorporation of a 3-ethylpyridine moiety

Lim JL, Sim KS, Yong KT, Loong BJ, Ting KN, Lim SH, et al.

Phytochemistry, 2015 Sep;117:317-24.
PMID: 26125941 DOI: 10.1016/j.phytochem.2015.06.024

Four alkaloids comprising two vallesamine, one strychnan, and one pyranopyridine alkaloid, in addition to 32 other known alkaloids were isolated from two Malayan Alstonia species, Alstonia pneumatophora and Alstonia rostrata. The structures of these alkaloids were determined using NMR and MS analyses, and in one instance, confirmed by X-ray diffraction analysis. The nor-6,7-secovallesamine alkaloid, pneumatophorine, is notable for an unusual incorporation of a 3-ethylpyridine moiety in a monoterpenoid indole. The rhazinilam-type alkaloids (rhazinicine, nor-rhazinicine, rhazinal, and rhazinilam) showed strong cytotoxicity toward human KB, HCT-116, MDA-MB-231, and MRC-5 cells, while pneumatophorine, the uleine alkaloid undulifoline, and the strychnan alkaloids, N4-demethylalstogustine and echitamidine, induced concentration dependent relaxation in phenylephrine-precontracted rat aortic rings.

Matched MeSH terms: Aldehydes/pharmacology; Aldehydes/chemistry
Fulltext Assessment of DNA strand breakage in streptozotocin-induced diabetic rats

Siti Balkis Budin, Norfadilah Rejab, Abdul Gapor Mohd Top, Wan Nazaimoon Wan Mohamud, Mokhtar Abu Bakar, Khairul Osman, et al.

Jurnal Sains Kesihatan Malaysia, 2005;3(1):2-12.
MyJurnal

This study was conducted to evaluate the oxidative damage in diabetic mellitus induced rats. The evaluation of DNA damage was carried out by the Alkaline Comet Assay using peripheral lymphocyte cells taken from streptozotocin-induced diabetic rats (50 mg/kg) and control rats. The levels of malondealdehyde (MDA), 4-hydroxynonenal (4-HNE), fasting blood glucose (FBG) and HbA1c were also measured. All the induced diabetic rats were hyperglycemic until the end of the study with significantly higher levels of FBG and HbA1c as compared to the control rats. The results showed the percentage of tail DNA and tail moment values were also significantly higher in the diabetic induced rats. The same observations were made on the levels of plasma MDA and 4-HNE. In conclusion, this study indicated that hyperglycemic condition in diabetic induced rats could generate oxidative DNA damage.

Matched MeSH terms: Aldehydes
Fulltext Anticancer Potential of Damnacanthal and Nordamnacanthal from Morinda elliptica Roots on T-lymphoblastic Leukemia Cells

Latifah SY, Gopalsamy B, Abdul Rahim R, Manaf Ali A, Haji Lajis N

Molecules, 2021 Mar 12;26(6).
PMID: 33808969 DOI: 10.3390/molecules26061554

BACKGROUND: This study reports on the cytotoxic properties of nordamnacanthal and damnacanthal, isolated from roots of Morinda elliptica on T-lymphoblastic leukaemia (CEM-SS) cell lines.
METHODS: MTT assay, DNA fragmentation, ELISA and cell cycle analysis were carried out.
RESULTS: Nordamnacanthal and damnacanthal at IC50 values of 1.7 μg/mL and10 μg/mL, respectively. At the molecular level, these compounds caused internucleosomal DNA cleavage producing multiple 180-200 bp fragments that are visible as a "ladder" on the agarose gel. This was due to the activation of the Mg2+/Ca2+-dependent endonuclease. The induction of apoptosis by nordamnacanthal was different from the one induced by damnacanthal, in a way that it occurs independently of ongoing transcription process. Nevertheless, in both cases, the process of dephosphorylation of protein phosphates 1 and 2A, the ongoing protein synthesis and the elevations of the cytosolic Ca2+ concentration were not needed for apoptosis to take place. Nordamnacanthal was found to have a cytotoxic effect by inducing apoptosis, while damnacanthal caused arrest at the G0/G1 phase of the cell cycle.
CONCLUSION: Damnacanthal and nordamnacanthal have anticancer properties, and could act as potential treatment for T-lymphoblastic leukemia.

Matched MeSH terms: Aldehydes/isolation & purification; Aldehydes/pharmacology*
Fulltext Antibacterial and Antispore Activities of Isolated Compounds from Piper cubeba L

Alqadeeri F, Rukayadi Y, Abbas F, Shaari K

Molecules, 2019 Aug 26;24(17).
PMID: 31454974 DOI: 10.3390/molecules24173095

Piper cubeba L. is the berry of a shrub that is indigenous to Java, Southern Borneo, Sumatra, and other islands in the Indian Ocean. The plant is usually used in folk traditional medicine and is an important ingredient in cooking. The purpose of this study was to isolate and purify the bioactive compounds from P. cubeba L. fractions. In addition, the isolated compounds were tested for their antibacterial and antispore activities against vegetative cells and spores of Bacilluscereus ATCC33019, B. subtilis ATCC6633, B.pumilus ATCC14884, and B.megaterium ATCC14581. The phytochemical investigation of the DCM fraction yielded two known compounds: β-asarone (1), and asaronaldehyde (2) were successfully isolated and identified from the methanol extract and its fractions of P. cubeba L. Results showed that exposing the vegetative cells of Bacillus sp. to isolated compounds resulted in an inhibition zone with a large diameter ranging between 7.21 to 9.61 mm. The range of the minimum inhibitory concentration (MIC) was between 63.0 to 125.0 µg/mL and had minimum bactericidal concentration (MBC) at 250.0 to 500.0 µg/mL against Bacillus sp. Isolated compounds at a concentration of 0.05% inactivated more than 3-Log10 (90.99%) of the spores of Bacillus sp. after an incubation period of four hours, and all the spores were killed at a concentration of 0.1%. The structures were recognizably elucidated based on 1D and 2D-NMR analyses (1H, 13C, COSY, HSQC, and HMBC) and mass spectrometry data. Compounds 1, and 2 were isolated for the first time from this plant. In conclusion, the two compounds show a promising potential of antibacterial and sporicidal activities against Bacillus sp. and thus can be developed as an anti-Bacillus agent.

Matched MeSH terms: Aldehydes/isolation & purification; Aldehydes/pharmacology*
Fulltext An efficient approach for the synthesis of novel methyl sulfones in acetic acid medium and evaluation of antimicrobial activity

Ravi Kumar G, Dasireddy CR, Varala R, Kotra V, Bollikolla HB

Turk J Chem, 2020;44(5):1386-1394.
PMID: 33488238 DOI: 10.3906/kim-2003-10

A series of nine methyl sulphones ( 3a -3 i ) starting from the aldehydes ( 1a-1i ) were synthesized in two consecutive steps. In the first step, preparation of allyl alcohols ( 2a-2i ) from their corresponding aldehydes by the reaction of sodium borohydride in methanol at room temperature is reported. Finally, methyl sulphones are synthesized by condensing sodium methyl sulfinates with allyl alcohols in the presence of BF 3 .Et 2 O in acetic acid medium at room temperature for about 2-3 h. The reaction conditions are simple, yields are high (85%-95%), and the products were obtained with good purity. All the synthesized compounds were characterized by their 1 H, 13 C NMR, and mass spectral analysis. All the title compounds were screened for antimicrobial activity. Among the compounds tested, the compound 3f has inhibited both Gram positive and Gram negative bacteria effectively and compound 3i has shown potent antifungal activity. These promising components may help to develop more potent drugs in the near future for the treatment of bacterial and fungal infections.

Matched MeSH terms: Aldehydes
A new anthraquinone from Morinda citrifolia roots

Ee GC, Wen YP, Sukari MA, Go R, Lee HL

Nat Prod Res, 2009;23(14):1322-9.
PMID: 19735047 DOI: 10.1080/14786410902753138

An investigation of Morinda citrifolia roots afforded a new anthraquinone, 2-ethoxy-1-hydroxyanthraquinone (1), along with five other known anthraquinones: 1-hydroxy-2-methylanthraquinone (2), damnacanthal (3), nordamnacanthal (4), 2-formyl-1-hydroxyanthraquinone (5) and morindone-6-methyl-ether (6). This is the first report on the isolation of morindone-6-methyl-ether (6) from this plant. The structures of these compounds were elucidated based on spectroscopic analyses such as NMR, MS and IR. Biological evaluation of five pure compounds and all the extracts against the larvae of Aedes aegypti indicated 1-hydroxy-2-methylanthraquinone (2) and damnacanthal (3) were the extracts to exhibit promising larvicidal activities.

Matched MeSH terms: Aldehydes/pharmacology; Aldehydes/chemistry
A functionally-distinct carboxylic acid reductase PcCAR4 unearthed from a repertoire of type IV CARs in the white-rot fungus Pycnoporus cinnabarinus

Ling JG, Mansor MH, Abdul Murad AM, Mohd Khalid R, Quay DHX, Winkler M, et al.

J Biotechnol, 2020 Jan 10;307:55-62.
PMID: 31545972 DOI: 10.1016/j.jbiotec.2019.09.008

Carboxylic acid reductases (CARs) are attracting burgeoning attention as biocatalysts for organic synthesis of aldehydes and their follow-up products from economic carboxylic acid precursors. The CAR enzyme class as a whole, however, is still poorly understood. To date, relatively few CAR sequences have been reported, especially from fungal sources. Here, we sought to increase the diversity of the CAR enzyme class. Six new CAR sequences from the white-rot fungus Pycnoporus cinnabarinus were identified from genome-wide mining. Genome and gene clustering analysis suggests that these PcCAR enzymes play different natural roles in Basidiomycete systems, compared to their type II Ascomycete counterparts. The cDNA sequences of all six Pccar genes were deduced and analysis of their corresponding amino acid sequence showed that they encode for proteins of similar properties that possess a conserved modular functional tri-domain arrangement. Phylogenetic analyses showed that all PcCAR enzymes cluster together with the other type IV CARs. One candidate, PcCAR4, was cloned and over-expressed recombinantly in Escherichia coli. Subsequent biotransformation-based screening with a panel of structurally-diverse carboxylic acid substrates suggest that PcCAR4 possessed a more pronounced substrate specificity compared to previously reported CARs, preferring to reduce sterically-rigid carboxylic acids such as benzoic acid. These findings thus present a new functionally-distinct member of the CAR enzyme class.

Matched MeSH terms: Aldehydes/metabolism
Fulltext A comparative analysis of the influence of human salivary enzymes on odorant concentration in three palm wines

Lasekan O

Molecules, 2013 Sep 25;18(10):11809-23.
PMID: 24071987 DOI: 10.3390/molecules181011809

The influence of human salivary enzymes on palm wines' odorant concentrations were investigated by the application of aroma extracts dilution analysis (AEDA) and by the calculation of odour activity values (OAVs), respectively. The odorants were quantified by means of stable isotope dilution assays (SIDA), and the degradation profiles of odorants by human saliva were also studied. Results revealed 46 odour-active compounds in the flavour dilution (FD) factor range of 4-256, and all were subsequently identified. Of the 46 odorants, 41 were identified in the Elaeis guineensis wine, 36 in Raphia hookeri wine and 29 in Borassus flabellifer wine. Among the odorants, the highest FD-factors were obtained from acetoin, 2-acetyl-1-pyrroline and 3-isobutyl-2-methoxypyrazine. Among the 13 potent odorants identified, five aroma compounds are reported here as important contributors to palm wine aroma, namely 3-isobutyl-2-methoxy-pyrazine, acetoin, 2-acetyl-1-pyrroline, 3-methylbutylacetate and ethyl hexanoate. Meanwhile, salivary enzymic degradation of odorants was more pronounced among the aldehydes, esters and thiols.

Matched MeSH terms: Aldehydes/chemistry
Fulltext A CONVENIENT SYNTHESIS OF 5-ARYLIDENE MELDRUM'S ACID DERIVATIVES VIA KNOEVENAGEL CONDENSATION

Adryana Izzati Adnan, noorhidayah977@uitm.edu.my, Nur Ain Nabilah Ash’ari

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2021;9(1):80-84.
MyJurnal

A series of ten 5-arylidene Meldrum’s acid derivatives had been synthesised in excellent yield via Knoevenagel condensation. This method does not require catalyst, or any further purification. Isopropylidene malonate (2,2-dimethyl-1,3-dioxane-4,6-dione), also known as Meldrum’s acid, is utilised as a core skeleton for various kind of reactions. Meldrum’s acid has features of a peculiar ring- opening sequences based on nucleophile-sensitive carbonyl functional groups at C-4 and C-6, which has made it possible for useful synthetic transformations, as well as its high acidity of methylene hydrogen at carbon position C-5. Hence, it allows the compound to be a flexible reagent for further reaction to prepare other derivatives. Therefore, Meldrum’s acid derivatives showed high potential of biological functions, such as antibacterial, antimalarial and antioxidant activities due to the olefinic linkage which played an important role in the enhancement of antimalarial activity. Furthermore, when arylidene Meldrum’s acid transformed to epoxide, the compound showed losses of antimalarial behaviour. Additionally, this compound has unique molecules due to the high acidity of methylene hydrogen at the carbon-5 position to initiate various reactions with different functional groups. In this research, Meldrum’s acid, 3 and ten its 5-arylidene derivatives (4a-e) and (5a-e) were synthesised by using two short and efficient reaction steps. The first step involved the condensation of malonic acid, 1 with acetone, 2 in acetic anhydride and acid via one-pot reaction to give Meldrum’s acid, 3 in 50% overall yield. Having Meldrum’s acid in hand, the reaction was proceeded with the Knoevenagel condensation reaction by using various functional groups, such as aryl aldehydes and aryl amines. All the synthesised compounds were characterised by using 1H and 13C spectroscopy.

Matched MeSH terms: Aldehydes