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Nishino C, Enoki N, Tawata S, Mori A, Kobayashi K, Fukushima M. Antibacterial Activity of Flavonoids againstStaphylococcus epidermidis, a Skin Bacterium. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/00021369.1987.10867965] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Zhu J, Majikina M, Tawata S. Syntheses and Biological Activities of Pyranyl-substituted Cinnamates. Biosci Biotechnol Biochem 2014; 65:161-3. [PMID: 11272821 DOI: 10.1271/bbb.65.161] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Twenty-two kinds of pyranyl-substituted cinnamates were synthesized by the reaction of 4-hydroxy-6-(2-phenylethyl)-2H-pyran-2-one or 4-hydroxy-6-methyl-2H-pyran-2-one (HMP) with a variety of substituted cinnamic acids, and their antifungal and plant growth inhibitory activities were investigated. Among the compounds prepared, 6-methyl-2-oxo-2H-pyran-4-yl 3-(4-isopropylphenyl)propenoate (H5) showed the strongest antifungal activity against Rhizoctonia solani and Sclerotium dellfinii, and 6-methyl-2-oxo-2H-pyran-4-yl 3-(2-methylphenyl)propenoate (H2) had the highest plant growth inhibitory activity toward Brassica rapa.
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Nguyen BCQ, Taira N, Tawata S. Several herbal compounds in Okinawa plants directly inhibit the oncogenic/aging kinase PAK1. Drug Discov Ther 2014; 8:238-44. [DOI: 10.5582/ddt.2014.01045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
Waste utilization in fruits and vegetable processing industries is one of the important and challengeable jobs around the world. It is anticipated that the discarded fruits as well as its waste materials could be utilized for further industrial purposes viz. fermentation, extraction of bioactive components, extraction of functional ingredients etc. Researchers have focused on the utilization of pineapple waste primarily for extraction of bromelain enzyme and secondarily as low-cost raw material for the production of ethanol, phenolic anti-oxidants, organic acids, biogas and fiber production. Pertinent scientific and technological implications would produce better and more profitable markets for pineapple wastes. This review is the collection of previous reports along with our ongoing work on utilization of pineapple wastes J. Food Sci. Technol. Nepal, Vol. 6 (10-18), 2010 DOI: http://dx.doi.org/10.3126/jfstn.v6i0.8255
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Chompoo J, Upadhyay A, Fukuta M, Tawata S. Effect of Alpinia zerumbet components on antioxidant and skin diseases-related enzymes. Altern Ther Health Med 2012; 12:106. [PMID: 22827920 PMCID: PMC3419607 DOI: 10.1186/1472-6882-12-106] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 07/24/2012] [Indexed: 11/22/2022]
Abstract
Background The skin is chronically exposed to endogenous and environmental pro-oxidant agents, leading to the harmful generation of reactive oxygen species. Antioxidant is vital substances which possess the ability to protect the body from damage cause by free radicals induce oxidative stress. Alpinia zerumbet, a traditionally important economic plant in Okinawa, contains several interesting bioactive constituents and possesses health promoting properties. In this regard, we carried out to test the inhibitory effect of crude extracts and isolated compounds from A. zerumbet on antioxidant and skin diseases-related enzymes. Methods The antioxidant activities were examined by DPPH, ABTS and PMS-NADH radical scavenging. Collagenase, elastase, hyaluronidase and tyrosinase were designed for enzymatic activities to investigate the inhibitory properties of test samples using a continuous spectrophotometric assay. The inhibitory capacity of test samples was presented at half maximal inhibitory concentration (IC50). Results The results showed that aqueous extract of the rhizome was found to have greater inhibitory effects than the others on both of antioxidant and skin diseases-related enzymes. Furthermore, 5,6-dehydrokawain (DK), dihydro-5,6-dehydrokawain (DDK) and 8(17),12-labdadiene-15,16-dial (labdadiene), isolated from rhizome, were tested for antioxidant and enzyme inhibitions. We found that DK showed higher inhibitory activities on DPPH, ABTS and PMS-NADH scavenging (IC50 = 122.14 ± 1.40, 110.08 ± 3.34 and 127.78 ± 4.75 μg/ml, respectively). It also had stronger inhibitory activities against collagenase, elastase, hyaluronidase and tyrosinase (IC50 = 24.93 ± 0.97, 19.41 ± 0.61, 19.48 ± 0.24 and 76.67 ± 0.50 μg/ml, respectively) than DDK and labdadiene. Conclusion Our results indicate that the rhizome aqueous extract proved to be the source of bioactive compounds against enzymes responsible for causing skin diseases. Moreover, DK could be used as a potent inhibitor and be further exploited to be used in anti-skin disease formulations.
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Chompoo J, Upadhyay A, Gima S, Fukuta M, Tawata S. Antiatherogenic properties of acetone extract of Alpinia zerumbet seeds. Molecules 2012; 17:6237-48. [PMID: 22634836 PMCID: PMC6268935 DOI: 10.3390/molecules17066237] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 11/23/2022] Open
Abstract
Oxidation of low-density lipoprotein (LDL) is the principal risk factor for the development of atherosclerosis. In this study, we used several methods to investigate the ability of the acetone extract from rhizomes, stems, leaves, flowers, pericarps and seeds of Alpinia zerumbet to inhibit atherosclerosis in vitro. The seed extract had the strongest activity against tyrosinase, pancreatic lipase (PL), 15-lipoxygenase (15-LO) and LDL oxidation activities (IC50 = 2.30 ± 0.02, 5.00 ± 0.07, 1.29 ± 0.07 and 15.40 ± 0.86 µg/mL, respectively), amongst all different parts. It also had similar effects to the positive controls. Most of the extracts showed partial agonistic properties towards estrogenic activity. Cholest-4-ene-3,6-dione, a steroid present only in the seed extract seems to be the compound responsible for these activities. The results showed that cholest-4-ene-3,6-dione had similar ability to curcumin and quercetin against PL and LDL oxidation (IC50 = 19.50 ± 1.17 and 16.12 ± 1.43 µg/mL, respectively). Furthermore, cholest-4-ene-3,6-dione (IC50 = 34.21 ± 1.31 µg/mL) had higher inhibition against 15-LO than quercetin (IC50 = 54.79 ± 1.12 µg/mL).
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Elzaawely AA, Tawata S. Antioxidant capacity and phenolic content of Rumex dentatus L. Grown in Egypt. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s12892-011-0063-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Upadhyay A, Chompoo J, Taira N, Fukuta M, Gima S, Tawata S. Solid-phase synthesis of mimosine tetrapeptides and their inhibitory activities on neuraminidase and tyrosinase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:12858-12863. [PMID: 22047208 DOI: 10.1021/jf203494t] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Neuraminidase is a rational target for influenza inhibition, and the search for neuraminidase inhibitors has been intensified. Mimosine, a nonprotein amino acid, was for the first time identified as a neuraminidase inhibitor with an IC(50) of 9.8 ± 0.2 μM. It was found that mimosine had slow, time-dependent competitive inhibition against the neuraminidase. Furthermore, a small library of mimosine tetrapeptides (M-A(1)-A(2)-A(3)) was synthesized by solid-phase synthesis and was assayed to evaluate their neuraminidase and tyrosinase inhibitory properties. Most of the tetrapeptides showed better activities than mimosine. Mimosine-FFY was the best compound, and it exhibited 50% neuraminidase inhibition at a low micromolar range of 1.8 ± 0.2 μM, whereas for tyrosinase inhibition, it had an IC(50) of 18.3 ± 0.5 μM. The kinetic studies showed that all of the synthesized peptides inhibited neuraminidase noncompetitively with K(i) values ranging from 1.9 -to 7.2 μM. These results suggest that mimosine could be used as a source of bioactive compounds and may have possibilities in the design of drugs as neuraminidase and tyrosinase inhibitors.
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Elzaawely A, Tawata S. Antioxidant Activity of Phenolic Rich Fraction Obtained from Convolvulus arvensis L. Leaves Grown in Egypt. ACTA ACUST UNITED AC 2011. [DOI: 10.3923/ajcs.2012.32.40] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Upadhyay A, Chompoo J, Araki N, Tawata S. Antioxidant, Antimicrobial, 15-LOX, and AGEs Inhibitions by Pineapple Stem Waste. J Food Sci 2011; 77:H9-15. [DOI: 10.1111/j.1750-3841.2011.02437.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ao C, Higa T, Khanh TD, Upadhyay A, Tawata S. Antioxidant phenolic compounds from Smilax sebeana Miq. Lebensm Wiss Technol 2011. [DOI: 10.1016/j.lwt.2011.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chompoo J, Upadhyay A, Kishimoto W, Makise T, Tawata S. Advanced glycation end products inhibitors from Alpinia zerumbet rhizomes. Food Chem 2011; 129:709-15. [PMID: 25212289 DOI: 10.1016/j.foodchem.2011.04.034] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 04/07/2011] [Accepted: 04/12/2011] [Indexed: 10/18/2022]
Abstract
Advanced glycation end products (AGEs) are major factors responsible for the complication of diabetes. The present study was carried out to investigate the inhibitory activities on fructosamine adduct and α-dicarbonyl formations by hexane extracts of various parts of Alpinia zerumbet. Furthermore, we isolated two previously known compounds, namely 5,6-dehydrokawain (DK) and dihydro-5,6-dehydrokawain (DDK). 8(17),12-Labdadiene-15,16-dial (labdadiene) was isolated for the first time from the rhizome of A. zerumbet. The results showed that labdadiene (IC50=51.06μg/mL) had similar activity to rutin and quercetin against fructosamine adduct. The inhibition of α-dicarbonyl compounds formation by labdadiene was significantly higher than that of DK and DDK. Our results indicate that labdadiene is a potent antiglycation agent which was found to inhibit AGEs formation in three different steps in the pathway. These data indicate that labdadiene could be used to prevent glycation-associated complications in diabetes.
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Upadhyay A, Chompoo J, Kishimoto W, Makise T, Tawata S. HIV-1 integrase and neuraminidase inhibitors from Alpinia zerumbet. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:2857-2862. [PMID: 21306110 DOI: 10.1021/jf104813k] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
AIDS and influenza are viral pandemics and remain one of the leading causes of human deaths worldwide. The increasing resistance of these diseases to synthetic drugs demands the search for novel compounds from plant-based sources. In this regard, the leaves and rhizomes of Alpinia zerumbet, a traditionally important economic plant in Okinawa, were investigated for activity against HIV-1 integrase (IN) and neuraminidase (NA). The aqueous extracts of leaves and rhizomes had IN inhibitory activity with IC(50) values of 30 and 188 μg/mL, whereas against NA they showed 50% inhibition at concentrations of 43 and 57 μg/mL, respectively. 5,6-Dehydrokawain (DK), dihydro-5,6-dehydrokawain (DDK), and 8(17),12-labdadiene-15,16-dial (labdadiene) were isolated from the rhizomes and were tested for enzyme inhibitions. DK and DDK strongly inhibited IN with IC(50) of 4.4 and 3.6 μg/mL, respectively. Against NA, DK, DDK, and labdadiene exhibited mixed type of inhibition with respective IC(50) values of 25.5, 24.6, and 36.6 μM and K(i) values ranging from 0.3 to 2.8 μM. It was found that DDK is a slow and time-dependent reversible inhibitor of NA, probably with a methoxy group as its functionally active site. These results suggest that alpinia could be used as a source of bioactive compounds against IN and NA and that DK and DDK may have possibilities in the design of drugs against these viral diseases.
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Ao C, Higa T, Ming H, Ding YT, Tawata S. Isolation and identification of antioxidant and hyaluronidase inhibitory compounds from Ficus microcarpa L. fil. bark. J Enzyme Inhib Med Chem 2010; 25:406-13. [DOI: 10.3109/14756360903213473] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Xuan TD, Toyama T, Fukuta M, Khanh TD, Tawata S. Chemical interaction in the invasiveness of cogongrass (Imperata cylindrica (L.) Beauv.). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:9448-53. [PMID: 19810700 DOI: 10.1021/jf902310j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
From gas chromatography-mass spectrometry (GC-MS), numerous plant growth inhibitors were found in the rhizome and root exudates of cogongrass, one of the most problematic weeds in the world. iso-Eugenol, iso-ferulic acid, linoleic acid, ferulic acid, and vanillin were the major chemicals in the rhizome (88.1-392.2 microg/g of fresh root), while 4-acetyl-2-methoxyphenol was the principle substance (872.6 microg/plant) in the root exudates. In fields, the use of cutting and plowing reduced weed biomass and weed density of cogongrass >70%. However, the alternative invasion of beggar tick might be a problem, because its density and biomass increased 33.3 and 62.5%, respectively. Chemicals from cogongrass showed selective effects against tested invasive species. Of them, 2,4-di-tert-butylphenol was the most potent (78.3-100% of inhibition), followed by iso-eugenol and 4-acetyl-2-methoxyphenol. These compounds may play important roles in the invasiveness of cogongrass and might be promising parent constituents of synthesis to develop novel herbicides for control of invasive plants.
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Ao C, Deba F, Tako M, Tawata S. Biological activity and composition of extract from aerial root ofFicus microcarpaL. fil. Int J Food Sci Technol 2009. [DOI: 10.1111/j.1365-2621.2008.01732.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ao C, Li A, A. Elzaawe A, Tawata S. MMP-13 Inhibitory Activity of Thirteen Selected Plant Species from Okinawa. INT J PHARMACOL 2008. [DOI: 10.3923/ijp.2008.202.207] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Deba F, Xuan TD, Yasuda M, Tawata S. Chemical composition and antioxidant, antibacterial and antifungal activities of the essential oils from Bidens pilosa Linn. var. Radiata. Food Control 2008. [DOI: 10.1016/j.foodcont.2007.04.011] [Citation(s) in RCA: 232] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Xuan TD, Fukuta M, Wei AC, Elzaawely AA, Khanh TD, Tawata S. Efficacy of extracting solvents to chemical components of kava (Piper methysticum) roots. J Nat Med 2007; 62:188-94. [PMID: 18404321 DOI: 10.1007/s11418-007-0203-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Accepted: 08/20/2007] [Indexed: 11/29/2022]
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Shiroma R, Uechi S, Tawata S, Tako M. Isolation and Characterization of Alginate from Hizikia fusiformis and Preparation of its Oligosaccharides. J Appl Glycosci (1999) 2007. [DOI: 10.5458/jag.54.85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Elzaawely AA, Xuan TD, Tawata S. Essential oils, kava pyrones and phenolic compounds from leaves and rhizomes of Alpinia zerumbet (Pers.) B.L. Burtt. & R.M. Sm. and their antioxidant activity. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.08.025] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Ishihara M, Shiroma T, Taira T, Tawata S. Purification and characterization of extracellular cysteine protease inhibitor, ECPI-2, from Chlorella sp. J Biosci Bioeng 2006; 101:166-71. [PMID: 16569614 DOI: 10.1263/jbb.101.166] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Accepted: 11/09/2005] [Indexed: 11/17/2022]
Abstract
An extracellular cysteine protease inhibitor (ECPI-2) was purified to homogeneity from the culture filtrate of Chlorella sp. 4533 by the combination of various column chromatographies. The molecular mass of the inhibitor was estimated to be 340 kDa by SDS-PAGE. The inhibitor was extremely heat-stable under acidic or neutral condition. ECPI-2 exhibited an inhibitory activity against the proteolytic activity of papain, ficin, or chymopapain, but not against stem bromelain or cathepsin B. The inhibitor showed no inhibitory activity against trypsin, alpha-chymotrypsin or thermolysin. ECPI-2 contains 33.6% carbohydrate residues by weight and inhibits papain at a molar ratio of 1:2. The proteolysis of the inhibitor by trypsin or alpha-chymotrypsin was apparent, but the inhibitory activity of ECPI-2 was unaffected by these enzymes. The alpha-chymotrypsin hydrolysis product from ECPI-2 was further separated into six fractions by gel filtration. From these results, it is suggested that ECPI-2 has several reactive sites for papain.
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Xuan TD, Chung IM, Khanh TD, Tawata S. Identification of phytotoxic substances from early growth of barnyard grass (Echinochloa crusgalli) root exudates. J Chem Ecol 2006; 32:895-906. [PMID: 16718576 DOI: 10.1007/s10886-006-9035-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 11/28/2005] [Accepted: 12/26/2005] [Indexed: 11/30/2022]
Abstract
Barnyard grass is a problematic weed worldwide. It competes with crops and causes reduction in crop yields. In this study, barnyard grass suppressed rice emergence, and the degree of rice inhibition was proportional to the density of barnyard grass. Root exudates of barnyard grass reduced germination and growth of lettuce, rice, and monochoria. Fifteen compounds potentially involved in the phytotoxic activities of barnyard grass were isolated and identified, including phenolics, long-chain fatty acids, lactones, diethyl phthalate, acenaphthene, and derivatives of phthalic acids, benzoic acid, and decane. Quantities of diethyl phthalate, decanoic acid, myristic acid, stearic acid, 7,8-dihydro-5,6-dehydrokavain, and 7,8-dihydrokavain were 2.7, 11.1, 19.6, 35.5, 10.3, and 15.5 microg/ml of barnyard grass root exudates, respectively. The two lactones exhibited the greatest inhibition, followed by the phenolics and the derivatives of phthalic acids. Fatty acids had stronger suppression than diethyl phthalate and ethyl ester-4-ethoxy-benzoic acid. The acenaphthene and decane derivatives were the least phytotoxic. The phytotoxins released by barnyard grass roots showed strong inhibition on growth of broadleaf indicator plants and paddy weeds, but were less effective on barnyard grass itself and rice. Our study revealed that in addition to competition, barnyard grass also interferes with rice and other plants in its surroundings by chemical means.
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Elzaawely AA, Xuan TD, Tawata S. Antioxidant and antibacterial activities of Rumex japonicus HOUTT. Aerial parts. Biol Pharm Bull 2006; 28:2225-30. [PMID: 16327154 DOI: 10.1248/bpb.28.2225] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We evaluated total phenolic content, antioxidant activity, reducing power and antibacterial activity of ethanol, hexane, chloroform, ethyl acetate and aqueous extracts of aerial parts of Rumex japonicus HOUTT. The ethyl acetate extract had the highest amount of phenolic compounds. It also exhibited the highest reducing power and antioxidant activity when assayed by the 1,1-diphenyl-2-picrylhydrazyl (DPPH), beta-carotene bleaching and superoxide radical methods. The ethyl acetate extract possessed the strongest antibacterial activity against Bacillus subtilis, B. cereus and E. coli. GC-MS analysis indicated that ethyl acetate extract contained a variety of phenolic compounds. HPLC analysis showed that pyrogallol was the predominant phenolic compound in this extract. Thus, our study verified that the ethyl acetate extract has strong antioxidant and antibacterial activities which are correlated with its high level of phenolic compounds, particularly pyrogallol and pyrocatechin. This extract of R. japonicus aerial parts can be utilized as an effective and safe source of antioxidants.
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Xuan TD, Elzaawely AA, Fukuta M, Tawata S. Herbicidal and Fungicidal Activities of Lactones in Kava (Piper methysticum). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:720-5. [PMID: 16448174 DOI: 10.1021/jf0519461] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
This is the first report showing that kava lactones are plant and plant fungus growth inhibitors. Aqueous extract of kava roots showed high allelopathic potential and strongly suppressed germination and growth of lettuce, radish, barnyardgrass, and monochoria. Nine kava lactones were detected using GC-MS including desmethoxyyagonin, kavain, 7,8-dihydrokavain, hydroxykavain, yagonin, 5,6,7,8-tetrahydroxyyagonin, methysticin, dihydromethysticin, and 11-hydroxy-12-methoxydihydrokavain. Quantities of desmethoxyyagonin, kavain, 7,8-dihydrokavain, yagonin, methysticin, and dihydromethysticin detected were 4.3, 6.9, 18.6, 5.7, 1.4, and 5.4 mg/g of dry weight, respectively. These six major lactones in kava roots showed great herbicidal and antifungal activities. Growth of lettuce and barnyardgrass were significantly inhibited at 1-10 ppm, and four plant fungi including Colletotrichum gloeosporides, Fusarium solani, Fusarium oxysporum, and Trichoderma viride were significantly inhibited at 10-50 ppm. The biological activities of kava lactones were characterized by different double-bond linkage patterns in positions 5,6 and 7,8. The findings of this study suggest that kava lactones may be useful for the development of bioactive herbicides and fungicides.
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