Records of Natural Products

Year: 2014 Volume: 8 Issue:3 July-September

Short Report

1) Xanthine Oxidase-Inhibitory Activity and Antioxidant Properties of the Methanol Extract and Flavonoids of Artemisia Asiatica

Rec. Nat. Prod. (2014) 8:3 ; 0 - 0
by Zsuzsanna Hajdú, Ana Martins, Orsolya Orbán-Gyapai, Peter Forgo, Nikoletta Jedlinszki, Imre Máthé, Judit Hohmann

The MeOH extract of the aerial parts of Artemisia asiatica significantly inhibited the xanthine oxidase (XO) induced uric acid production. Flavonoids were isolated from the active extract and identified as eupatilin (1), hispidulin (2), jaceosidin (3), cirsilineol (4), 5,7,4’,5’-tetrahydroxy-6,3’-dimethoxyflavone (5), 6-methoxytricin (6) and chrysosplenetin (7). With the exception of cirsilineol and chrysoplenetin, all these flavonoids exerted marked XO-inhibitory effects, with IC 50 values in the range 1.33−6.13 µM. The degree of XO inhibition by 1-3, 5 and 6 suggests the importance of the free OH group on C-7. Evaluation of the isolated compounds 1-7 for their free radical scavenging activity in DPPH tests, revealed the substantial antioxidant activity of 5,7,4’,5’-tetrahydroxy-6,3’-dimethoxy-flavone (5), which contains ortho-dihydroxy and 5-hydroxy groups. In summary, the flavonoid-containing MeOH extract of A. asiatica exhibits dual action, inhibiting XO (1-3, 5, 6) and resulting in a reduced generation of reactive oxygen species, and additionally scavenging free radicals (5).

Keywords
Artemisia asiatica Asteraceae Flavonoids Xanthine oxidase inhibitory activity Antioxidant activity. © 2014 ACG Publications. All rights reserved.
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Short Report

2) Secondary Metabolites from Jacaranda mimosifolia and Kigelia africana (Bignoniaceae) and their Anticandidal Activity

Rec. Nat. Prod. (2014) 8:3 ; 0 - 0
by Lazare Sidjui Sidjui, Elisabeth Menkem Zeuko’o, Rufin Marie Kouipou Toghueo, Olivier Placide Noté, Valérie Mahiou-Leddet, Gaëtan Herbette, Fabrice Boyom Fekam, Evelyne Ollivier and Gabriel Ngosong Folefoc

Fr om the stem barks of Jacaranda mimosifolia benzoic acid (1), 1-naphthaleneacetic acid, 5-carboxy-1,2,3,4,4a,7,8,8a-octahydro-1,2,4a-trimethyl-[1S-(1α,2β,4aβ,8aα)] (2), betulinic acid (3), lupeol (4) and ursolic acid (5) were isolated. Similarly, lapachol (6), dehydro-α-lapachone (7), 2- acetylfuro-1, 4-naphthoquinone (8), p-coumaric acid (9), caffeic acid (10), nonacosanoic acid, 2-(4-hydroxyphenyl)ethyl ester (11), β-sitosterol (12), kigelinol (13), oleanolic acid (14), β-friedelinol (15), pomolic acid (16), and kojic acid (17) were isolated from the stem barks of Kigelia africana . All the isolated compounds were characterized by using spectroscopic methods especially 1D and 2D NMR and ESI mass spectrometry and comparison with literature data. To the best of our knowledge, compounds 1, 2, 3 and 5, and compounds 11, 14, 15 and 16 were isolated for the first time from Jacaranda mimosifolia and Kigelia africana, respectively. All these compounds were screened for anticandidal activity by agar diffusion method and microbroth dilution technique on four Candida albicans strains (ATCC L26, ATCC12C, ATCCP37039, and ATCCP37037). Among them, compounds 9, 10, and 17 exhibited the highest anticandidal activity that varied between the microbial species (MIC= 0.01 ± 0.00 − 0.03 ± 0.00 mg/mL) on C. albicans ATCC L26, ATCCP37037, ATCCP37039 and ATCC12C strains. Compound 17 was likely the most active against the four Candida albicans strains (MIC= 0.01 ± 0.00 − 0.02 ± 0.00 mg/mL).

Keywords
Bignoniaceae Jacaranda mimosifolia Kigelia africana anticandidal activity.
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Short Report

3) Phytochemicals from the Bark of Garcinia hombroniana and Their Biological Activities

Rec. Nat. Prod. (2014) 8:3 ; 0 - 0
by Nargis Jamila, Melati Khairuddean, Sadiq Noor Khan , Naeem Khan and Hasnah Osman

The dichloromethane and ethyl acetate extracts from the bark of Garcinia hombroniana yielded lupeol (1), lupeol acetate (2), 3β-acetoxy- lup-12,20(29)-diene (3), β-sitosterol (4), 22-dehydroclerosterol (5), mangiferolic acid (6), ursolic acid (7), betulin (8), betulinic acid (9), 1,3,6-trihydroxy-7-methoxy-2,8-(3-methyl-2-butenyl)xanthone (10), leucodin (11), p-hydroxycinnamate (12), p-hydroxybenzoic acid (13) and stearic acid (14). Compounds 10,12 and 13 exhibited significant antioxidant activities by DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) and FRAP (ferric ion reducing antioxidant power) assays. Antibacterial studies showed strong inhibitory effects for compound 11 while other compounds (1-9and 14) were either inactive or moderately active for the bacterial strains investigated. This study presents the first report on the isolation and biological activities of the chemical constituents from the bark of G. hombroniana. The compounds 3, 5-12 and 14 are reported for the first time from this source.

Keywords
Garcinia hombroniana bark triterpenoids antioxidant activities antibacterial activities .
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Original Article

4) New Cyclolignans from Origanumglandulosum Active Against b -amyloid Aggregation

Rec. Nat. Prod. (2014) 8:3 ; 208 - 216
by Abdelkader Basli, Jean-Claude Delaunay, Eric Pedrot, Stéphane Bernillon, Khodir Madani, Jean-Pierre Monti, Jean Michel Mérillon, Mohamed Chibane, Tristan Richard

Origanum glandulosum Desf is an endemic flavoring herb widely distributed in North Africa that is commonly used in traditional medicine. This oregano species is rich in essential oils but little is known about its phenolic composition. In the present study, a crude extract of O. glandulosum was prepared in order to isolate and investigate its neuroprotective potential to inhibit β-amyloid peptide (Aβ) aggregation. The three major compounds of the extract were isolated: rosmarinic acid and two cyclolignans in Origanum genus, globoidnan A and a new derivative named globoidnan B. Rosmarinic acid and globoidnan A showed significant anti-aggregative activity against β amyloid aggregation (IC50 7.0 and 12.0 µM, respectively). In contrast, globoidnan B was found to be less active

Keywords
Origanum glandulosum oregano cyclolignans β-Amyloid aggregation NMR.
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Original Article

5) Characterization and Antioxidant Properties of the Condensed Tannins from Alaska Cedar Inner Bark

Rec. Nat. Prod. (2014) 8:3 ; 217 - 227
by Martha Rosales-Castro, Rubén F. González-Laredo, Young-Soo Bae, Jin Kgu Kim, Jeff Morre, and Joseph J. Karchesy

The structure and antioxidant activity of condensed tannins isolated from Alaska Cedar inner bark have been investigated. Oligomers of flavan-3-ol were purified by column chromatography (Sephadex LH-20) and analyzed by 13CNMR and MALDI-TOF MS spectrometries. Their antioxidant activities were measured using 1,1’-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) free radicals scavenging, ferric reducing/antioxidant power (FRAP), and β-carotene-linoleic acid model system (β-CLAMS) assays. Results showed that the condensed tannins consents of both homogeneous and heterogeneous oligomers of procyanidins (catechin/epicatechin) and prodelphinidins (gallocatechin/ epigallocatechin) flavan-3-ol units; and oligomers from trimmers to heptamers with dominant interflavan linkages B-type as it is most common in proanthocyanidins. Condensed tannins showed significant ntioxidant activity as the median inhibition capacity IC 50 is comparable to the catechin control response. Alaska Cedar inner bark oligomers show high antioxidant capacity, evaluated by both methods based on electron transfer mechanisms and hydrogen atom transfer reactions. This bark may be considered as a new source of natural antioxidants for nutraceutical ingredients

Keywords
Chamaecyparis nootkatensis MALDI-TOF Proanthocyanidins ABTS DPPH FRAP.
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Original Article

6) Saponins from Cephalaria aristata C. Koch

Rec. Nat. Prod. (2014) 8:3 ; 228 - 233
by Derya Gülcemal, Milena Masullo, Serdar Gökhan Şenol, Özgen Alankuş-Çalışkan, and Sonia Piacente

One new oleanane-type saponin, 3-O-β-D-glucopyranosyl-(1→4)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester (1) was isolated from the MeOH extract of whole plant parts of Cephalaria aristataC. Koch along with three known oleanane-type saponins (2-4), 3-O- α -L-rhamnopyranosyl-(1→2)- α -L-arabinopyranosyl hederagenin 28-O-( β -D-glucopyranosyl-(1→6)- β -D-glucopyranosyl) ester, 3-O- β -D-glucopyranosyl-(1→4)- β -D-xylopyranosyl-(1→3)- α -L-rhamnopyranosyl-(1→2)- α -L-arabinopyranosyl hederagenin and 3-O- α -L-rhamnopyranosyl-(1→2)- α -L-arabinopyranosyl hederagenin respectively, (5-7), oleanolic acid (5), β -amyrin (6) and 20 β -hydroxyursolic acid (7) and one sterol glucoside (8), 29-hydroxystigmast-5-en-3-O- β -D-glucopyranosyde. Their structures were established by the extensive use of 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis.

Keywords
Cephalaria aristata Dipsacaceae Oleanane-type saponins. © 2014 ACG Publications. All rights reserved.
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Original Article

7) Lignan Glycosides from Gentianella acuta (Michx.) Hulten. and Their Protective Effects Against H 2O 2-Induced Apoptosis in H9c2 Cardiomyoblasts

Rec. Nat. Prod. (2014) 8:3 ; 234 - 241
by Ying Yu , Zhi-Bin Wang , Ya-Dong Zhai, Pu-Yuan Song, Qiu-Hong Wang, Bing-You Yang and Hai-Xue Kuang

 T wo new lignan glycosides named acutosides A (1) and B (2) have been isolated from the whole plant of Gentianella acute (Michx) Hulten. and t heir structures were determined as (-)-(7 R ,8S,7'E)-4-hydroxy-3, 3 '-dimethoxy-7,4'-epoxy-8, 5 '-neolign-7'-ene-9,9'-diol 9'-ethyl ether -4-O-β-D- glucopyranosid e and (-)-(7 R ,8S,7'E)-4-hydroxy-3, 3 '-dimethoxy-7,4'-epoxy-8, 5 '-neolign-7'-ene-9,9'-diol 9-ethyl ether -9 ' -O-β-D- glucopyranosid e by means of 1D-, 2D-NMR , HR -ESI -MS , CD techniques and chemical reactions. Along with the above two new compounds we got six known ones: (7R,8S)-dehydrodiconiferyl alcohol-4,9 ' -di-O-β-D- glucopyranosid e (3 ), alaschanisoside A (4 ), citrusin A (5 ) , 8,4',9'-trihydroxy-3,3'-dimethoxy-9,7'-epoxylignan 4-O- β -D- glucopyranosid e (6 ), l eptolepisol D (7 ) and acanthoside D (8 ). The cardioprotective effects of compounds 1-8 were evaluated by measuring the viability of the compounds 1-8 pretreated H9c2 cardiomyoblasts after exposure to H 2O 2-induced apoptosis, the results showed that compounds 1,3,6,8which could increase cell viability >15% at 200 μM had remarkably protective influence against H 2O 2-induced apoptosis. All the compounds were tested for cytotoxicity against two human tumor cell lines: gastric cancer SGC-7901 and breast cancer MCF-7. But they were inactive (IC 50>40 μM).

Keywords
Lignan glycosides Gentianella acute (Michx.) Hulten. H9c2 Cardiomyoblasts cardioprotective activity.
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Original Article

8) Chemical Diversity and Biological Activity of the Volatiles of Five Artemisia Species from Far East Russia

Rec. Nat. Prod. (2014) 8:3 ; 242 - 261
by Gulmira Özek, Yerlan Suleimen, Nurhayat Tabanca, Roman Doudkin, Petr G. Gorovoy, Fatih Göger, David E. Wedge, Abbas Ali, Ikhlas A. Khan and Kemal Hüsnü C. Başer

Artemisia argyiA. feddeiA. gmeliniiA. manshurica, and A. olgensis (Asteraceae) were collected in Far East Russia. Oils were hydrodistilled and simultaneously analyzed by GC-FID and GC/MS. Main constituents were found as follows in Artemisia oils: selin-11-en-4 a -ol (18.0%), 1,8-cineole (14.2.0%), artemisia alcohol (12.9%), borneol (9.7%) in A. argyi; camphor (31.2%), 1,8-cineole (17.6%), a -thujone (5.7%) in A. feddei; longiverbenone (12.0%), isopinocamphone (8.9%), 1,8-cineole (6.7%), camphor (5.8%), trans-p-menth-2-en-1-ol (5.3%) in A. gmelinii; germacrene D (11.2%), rosifoliol (10.1%), caryophyllene oxide (6.8%), eudesma-4(15),7-dien-1 b -ol (5.6%) in A. manshurica; eudesma-4(15),7-dien-1 b -ol (6.9%), caryophyllene oxide (5.6%), guaia-6,10(14)-dien-4 b -ol (5.1%) and hexadecanoic acid (5.0%) in A. olgensis. Oils were subsequently submitted for antifungal and antimosquito evaluations. Artemisia species oils showed biting deterrent effects in Aedes aegypti and Artemisia gmelinii oil with the most active biting deterrence index values of 0.82 ± 0.1 at 10 m g/mL. Larval bioassay of A. gmelinii and A. olgensis oils showed higher larvicidal activity against Ae. aegypti larvae with LD50 values of 83.8 (72.6 – 95.7) ppm and 91.0 (73.8 – 114.5) ppm, respectively. Antifungal activity was evaluated against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatumC. fragariae and C. gloeosporioides using direct overlay bioautography assay and all showed non-selective weak antifungal activity. Antioxidant evaluations of the oils were performed by using b -carotene bleaching, Trolox equivalent and DPPH tests. The tested Artemisia oils demonstrated moderate antioxidant activity.

Keywords
Artemisia essential oil antifungal botanical insecticidal mosquito control antioxidant activity.
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Original Article

9) Combination of Quercetin and Kaempferol Enhances in Vitro Cytotoxicity on Human Colon Cancer (HCT-116) Cells

Rec. Nat. Prod. (2014) 8:3 ; 262 - 271
by Sara Jaramillo-Carmona1, Sergio Lopez, Rocio Abia, Rocio Rodriguez-Arcos, Ana Jimenez, Rafael Guillen and Francisco J.G. Muriana

Colon cancer is one of the most common types of cancer malignancy. Although flavonoids naturally occur as mixtures, little information is available regarding the additive or synergistic biochemical interactions between flavonoids. The objectives of this study were to examine the feasibility of combining two major structurally related flavonoids, quercetin and kaempferol, to affect the cell viability, cell cycle, and proliferation of the human colon cancer HCT-116 cell line. The combination of quercetin and kaempferol exhibited a greater cytotoxic efficacy than did either quercetin or kaempferol alone. This effect was highest and acted in a synergistic fashion in a 2-fold quercetin and 1-fold kaempferol IC50 combination, which also arrested cell growth in the G2/M phase and suppressed proliferation. Our observations support a structure-activity relationship based on the presence of 3’–OH moiety and/or 4’–OH moiety on the B-ring of flavonoids. 

DOI
Keywords
Quercetin; kaempferol; colon cancer; cytotoxicity; synergy
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Short Report

10) Hylotelephium Spectabile (Boreau) H. Ohba x Telephium (L.) H.Ohba Leaf and Flower Extracts: Composition, Antioxidant and Antibacterial Activity

Rec. Nat. Prod. (2014) 8:3 ; 272 - 276
by Gordana Stojanović, Snežana Jovanović, Bojan Zlatković, Aleksandra Đorđević, Goran Petrović, Olga Jovanović, Vesna Stankov-Jovanović and Violeta Mitić

Composition, antioxidant and antibacterial activities for methanol extracts, and their hexane, ethyl acetate and butanol fractions of the fresh leaf and flower of Hylotelephium spectabile x telephium were studied for the first time. The extracts contain mostly quercetin and kaempferol glycosides, as confirmed by the composition of hydrolysates whose main components were quercetin and kaempferol. Evaluations of antioxidant activity were done by the following assays: DPPH, ABTS and total reducing power assay (Fe 3+ to Fe 2+). Additionally, total flavonoid content and total phenols were determined. The antioxidant capacity of ethyl acetate flower fraction was very close or even higher than capacity of used standard antioxidants. Presented results qualify this species as a potential new source of antioxidant substances. Ethyl acetate fraction of leaf showed moderate bactericidal activity against P. aeruginosa, S. typhimurium, S. aureus, and B. subtilis.

Keywords
Hylotelephium spectabile flavonoids antioxidant and antibacterial activity.
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Short Report

11) Complete Isolation and Characterization of Polar Portion of Mentha dumetorum Water Extract

Rec. Nat. Prod. (2014) 8:3 ; 277 - 280
by Hüseyin Akşit, Süleyman M. Çelik, Özkan Şen, Ramazan Erenler, İbrahim Demirtaş, İsa Telci and Mahfuz Elmastaş

 Four flavon glycosides, eriocitrin (1), luteolin-7-O-rutinoside (2), hesperidin (3), apigenin-7-O-rutinoside (4) and rosmarinic acid (5) were isolated from the aerial parts of Mentha dumetorum (Lamiaceae) for the first time. The structural elucidations of isolated compounds were achieved using spectral methods (1D- and 2D-NMR, and LC-TOF-HRMS).

Keywords
Mentha dumetorum flavon glycosides rosmarinic acid.
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Short Report

12) Seasonal Variation in Essential oil Composition of Artemisianilagirica var. septentrionalis from Foot Hills of Western Himalaya

Rec. Nat. Prod. (2014) 8:3 ; 281 - 285
by Rajendra Chandra Padalia, Ram Swaroop Verma, Amit Chauhan and Chandan Singh Chanotiya

Essential oils composition of the aerial parts of Artemisia nilagirica (Clarke) Pamp. var. septentrionalis Pamp. in different seasons viz. spring, summer, rainy, autumn and winter seasons under foot hills agroclimatic conditions of western Himalaya were analyzed and compared by GC–FID and GC–MS. Essential oils were mainly composed of monoterpenoids (59.0%-77.3%) and sesquiterpenoids (15.7%-31.6%). The major constituents identified were artemisia ketone (38.3%-61.2%), chrysanthenone (1.5%-7.7%), germacrene D (3.1%-6.8%), β-caryophyllene (1.9%-6.8%), germacra-4,5,10-trien-1-α-ol (1.9%-4.9%) and artemisia alcohol (1.4%-3.6%). Compositional analysis showed significant variations in the terpenoid compositions due to seasonal variations. Further, this is for the first time the seasonal variations in essential oil compositions of artemisia ketone rich chemotype of A. nilagirica var. septentrionalis is being reported from India.

Keywords
Artemisia nilagirica essential oils artemisia ketone β-caryophyllene germacrene D
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Short Report

13) New Inhibitors of the DENV-NS5 RdRp from Carpolepis laurifolia as Potential Antiviral Drugs for Dengue Treatment

Rec. Nat. Prod. (2014) 8:3 ; 286 - 289
by Paul Coulerie, Alexandre Maciuk, Cécilia Eydoux, Edouard Hnawia, Nicolas Lebouvier, Bruno Figadère, Jean-Claude Guillemot and Mohammed Nour

Since a few decades the dengue virus became a major public health concern and no treatment is available yet. In order to propose potential antidengue compounds for chemotherapy we focused on DENV RNA polymerase (DENV-NS5 RdRp) which is specific and essential for the virus replication. Carpolepis laurifolia belongs to the Myrtaceae and is used as febrifuge in traditional kanak medicine. Leaf extract of this plant has been identified as a hit against the DENV-NS5 RdRp. Here we present a bioguided fractionation of the leaf extract of C. laurifolia which is also the first phytochemical evaluation of this plantFive flavonoids, namely quercetin (1), 6-methyl-7-methoxyapigenin (2), avicularin (3), quercitrin (4) and hyperoside (5), together with betulinic acid (6), were isolated from the leaf extract of C. laurifolia. All isolated compounds were tested individually against the DENV-NS5 RdRp and compared with four other commercial flavonoids: isoquercitrin (7), spiraeoside (8), quercetin-3,4’-di-O-glucoside (9) and rutine (10). Compounds 3, 4, 6, 8 and 10 displayed IC 50 ranging from 1.7 to 2.1 µM, and were the most active against the DENV-NS5 RdRp.

Keywords
Carpolepis laurifolia Dengue Virus Flavonoids Triterpenes.
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Short Report

14) Mexicanolide- and Andirobine-type Limonoids from the Fruits of Guarea kunthiana

Rec. Nat. Prod. (2014) 8:3 ; 290 - 293
by Carlos Henrique Miguita, Ulana Chaves Sarmento, Lidilhone Hamerski, Walmir Silva Garcez and Fernanda Rodrigues Garcez

Four limonoids, humilinolide E (1) , methyl 2-hydroxy-3 b -tigloyloxy-1-oxomeliac-8(30)-enate (2), swietenine acetate (3) and methyl angolensate (4) were isolated from the fruits of Guarea kunthiana. Compounds 1-3 are being reported for the first time in the genus Guarea, while 4 has been previously described in only one species of this genus. The isolated compounds were identified by spectral methods (1D-, 2D-NMR and EIMS).

Keywords
Limonoids Meliaceae Guarea kunthiana
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Short Report

15) A Trimeric Proanthocyanidin from the Bark of Acacia leucophloea Willd.

Rec. Nat. Prod. (2014) 8:3 ; 294 - 298
by Sarfaraz Ahmed, Hsiao-Ching Lin, Iram Nizam, Nadeem Ahmad Khan, Shoei-Sheng Lee and Nizam Uddin Khan

 (–)-Fisetinidol-(4α,8)-[(–)-fisetinidol-(4α,6) ]-(+)-catechin ( 1 ), a proanthocyanidin, was isolated from the bark of Acacia leucophloea . Its structure including absolute configuration was elucidated on the basis of spectroscopic analysis and chemical correlation . The 1H NMR spectrum of this compound, exhibiting exceptional complex signals attributable to rotational isomerism, and the reported data were obtained at elevated temperature in methyl ether acetate form. This work provided the 1H and 13C NMR assignments for 1 and its rotational isomer as the free phenolic form at ambient temperature for the first time. Compound 1 showed inhibitory activity against α-glucosidase type IV from Bacillus stearothermophilus with the IC 50 value of 102.3 μM.

Keywords
Acacia leucophloea Mimosaceae α-Glucosidase inhibitor proanthocyanidin.
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Short Report

16) Tyrosinase Inhibitory Chemical Constituents from Cleyera japonica Thunberg Branches

Rec. Nat. Prod. (2014) 8:3 ; 303 - 306
by Jung Eun Kim, Tae-Heon Oh, Chang-Gu Hyun and Nam Ho Lee

Bioassay-guided investigation of the branches of Cleyera japonica led to the isolation of four phenolic constituents: 3,3’-di-O-methylellagic acid (1), 3,3’-di-O-methylellagic acid 4’-O-β-D-xylofuranoside (2),  3,5,7-trihydroxychromone 3-O-α-L-arabinofuranoside (3) and aviculin (4). Their structures were elucidated on the basis of spectral studies, as well as by comparison with literature data. Tyrosinase inhibition activities were carried out for the isolated compounds using arbutin as a positive control. Among them, compound 2 was identified as a potent tyrosinase inhibitor. It inhibited mushroom tyrosinase with an IC50 value of 0.078 mM, which is about three times more active than arbutin (IC50 =0.25 mM). All of the compounds 1-4 were isolated for the first time from this plant. 

Keywords
Cleyera japonica isolation phenolic compounds tyrosinase inhibition
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