Several natural compounds deriving from plants are known to be efficient anti-amyloid aggregation agents. In this study, anti-aggregation activity of grapefruit seed extract was investigated using trypsin as a model protein in aqueous ethanol at pH 7.0. Using turbidity measurement, Congo red (CR) binding assay, electronic circular dichroism (ECD) and transmission electron microscopy (TEM), we found that grapefruit seed extract has ability to inhibit trypsin amyloidlike fibril formation in vitro, and effectiveness increases with growing concentration of grapefruit seed extract. The total phenolic content of it was determined. The results showed that in addition to the polyphenolic compounds some other compounds are also responsible for the fibril formation inhibitory effect. We indicated it for the first time that limonin has anti-fibrillation effect.
YiuC.P.B., ChenY.W. (2017) From disorder to mis-order: Structural aspects of pathogenic oligomerization in conformational diseases. Protein & Peptide Letters, 24, 307–314.
2.
KhanE., MishraS.K., KumarA. (2017) Emerging methods for structural analysis of protein aggregation. Protein & Peptide Letters, 24, 331–339.
3.
NieR.Z., ZhuW., PengJ.M., GeZ.Z., LiC.M. (2016) A-type dimeric epigallocatechin-3-gallate (EGCG) is a more potent inhibitor against the formation of insulin amyloid fibril than EGCG monomer. Biochimie, 125, 204–212.
4.
PoratY., AbramowitzA., GazitE. (2006) Inhibition of amyloid fibril formation by polyphenols: structural similarity and aromatic interactions as a common inhibition mechanism. Chemical Biology & Drug Design, 67, 27–37.
5.
BuX.L., RaoP.P.N., WangY.J. (2016) Anti-amyloid aggregation activity of natural compounds: Implications for Alzheimer's drug discovery. Molecular Neurobiology, 53, 3565–3575.
6.
GanzeraM., AberhamA., StuppnerH. (2006) Development and validation of an HPLC/UV/MS method for simultaneous determination of 18 preservatives in grapefruit seed extract. Journal of Agricultural and Food Chemistry, 54, 3768–3772.
7.
BrzozowskiT., KonturekP.C., DrozdowiczD., KonturekS.J., ZayachivskaO., PajdoR., KwiecienS., PawlikW.W., HahnE.G. (2005) Grapefruit-seed extract attenuates ethanol-and stress-induced gastric lesions via activation of prostaglandin, nitric oxide and sensory nerve pathways. World Journal of Gastroenterology, 11, 6450–6458.
8.
XuW.T., QuW., HuangK.L., GuoF., YangJ.J., ZhaoH., LuoY.B. (2007) Antibacterial effect of Grapefruit Seed Extract on food-borne pathogens and its application in the preservation of minimally processed vegetables. Postharvest Biology and Technology, 45, 126–133.
9.
KimS.Y., ShinK.S. (2012) Antimicrobial activity of trifoliate orange (Poncirus trifoliate) seed extracts on gram-negative food-borne pathogens. Preventive Nutrition and Food Science, 17, 228–233.
10.
BrorsonO., BrorsonS.H. (2007) Grapefruit seed extract is a powerful in vitro agent against motile and cystic forms of Borrelia burgdorferi sensu lato. Infection, 35, 206–208.
11.
OzakiY., FongC.H., HermanZ., MaedaH., MiyakeM., IfukuY., HasegawaS. (1991) Limonoid glucosides in citrus seeds. Agricultural and Biological Chemistry, 55, 137–141.
12.
GualdaniR., CavalluzziM.M., LentiniG., HabtemariamS. (2016) The chemistry and pharmacology of citrus limonoids. Molecules, 21, 1530.
13.
FanY., ChenY., ChenJ., ZhangF., OndiekiG., LiY., HeX. (2017) Inhibition of Cytochrome P450 by Nomilin and Obacunone and Potential Mechanism in Human Liver Microsomes. Chinese Herbal Medicines, 9, 295–298.
14.
HeoH.J., KimD.O., ShinS.C., KimM.J., KimB.G., ShinD.H. (2004) Effect of antioxidant flavanone, naringenin, from Citrus junos on neuroprotection. Journal of Agricultural and Food Chemistry, 52, 1520–1525.
15.
RegitzC., FitzenbergerE., MahnF.L., DusslingL.M., WenzelU. (2016) Resveratrol reduces amyloid-beta (Aβ1-42)-induced paralysis through targeting proteostasis in an Alzheimer model of Caenorhabditis elegans.European Journal of Nutrition, 55, 741–747.
16.
SinghS.K., SrivastavS., YadavA.K., SrikrishnaS., PerryG. (2016) Overview of Alzheimer's disease and some therapeutic approaches targeting Aβ by using several synthetic and herbal compounds. Oxidative Medicine and Cellular Longevity, 2016, 7361613.
17.
TuL.H., YoungL.M., WongA.G., AshcroftA.E., RadfordS.E., RaleighD.P. (2015) Mutational analysis of the ability of resveratrol to inhibit amyloid formation by islet amyloid polypeptide: critical evaluation of the importance of aromatic-inhibitor and histidine-inhibitor interactions. Biochemistry, 54, 666–676.
18.
ShariatiziS., MeratanA.A., GhasemiA., Nemat-GorganiM. (2015) Inhibition of amyloid fibrillation and cytotoxicity of lysozyme fibrillation products by polyphenols. International Journal of Biological Macromolecules, 80, 95–106.
19.
MaB., ZhangF., LiuY., XieJ., WangX. (2017) Resveratrol induces the conversion from amyloid to amorphous aggregation of β-lactoglobulin. Protein & Peptide Letters, 24, 1113–1119.
20.
CoxC.J., ChoudhryF., PeaceyE., PerkintonM.S., RichardsonJ.C., HowlettD.R., LichtenthalerS.F., FrancisP.T., WilliamsR.J. (2015) Dietary (-)-epicatechin as a potent inhibitor of βγ-secretase amyloid precursor protein processing. Neurobiolology of Aging, 36, 178–187.
21.
CarbonaroM., Di VenereA., FilabozziA., MaselliP., MinicozziV., MoranteS., NicolaiE., NucaraA., PlacidiE., StellatoF. (2016) Role of dietary antioxidant (-)-epicatechin in the development of β-lactoglobulin fibrils. Biochimica et Biophysica Acta, 1864, 766–772.
22.
KotormánM., SimonL.M., BoricsA., SzabóM.R., SzabóK., SzögiT., FülöpL. (2015) Amyloid-like fibril formation by trypsin in aqueous ethanol. Inhibition of fibrillation by PEG. Protein & Peptide Letters, 22, 1104–1110.
23.
ZhaoR., SoM., MaatH., RayN.J., ArisakaF., GotoY., CarverJ.A., HallD. (2016) Measurement of amyloid formation by turbidity assay-seeing through the cloud. Biophysical Reviews, 8, 445–471.
24.
KotormánM., KasiP.B., HalászL., BoricsA. (2017) Inhibition of amyloid-like fibril formation of trypsin by red wines. Protein & Peptide Letters, 24, 466–470.
25.
CvetnićZ., Vladimir-KnezevićS. (2004) Antimicrobial activity of grapefruit seed and pulp ethanolic extract. Acta Pharmaceutica, 54, 243–250.
26.
VenkatesanR., JiE., KimS.Y. (2015) Phytochemicals that regulate neurodegenerative disease by targeting neurotrophins: a comprehensive review. BioMed Research International, 2015, 814068.
27.
YoonJ.S., YangH., KimS.H., SungS.H., KimY.C. (2010) Limonoids from Dictamnus dasycarpus protect against glutamate-induced toxicity in primary cultured rat cortical cells. Journal of Molecular Neuroscience, 42, 9–16.
28.
GirychM., GorbenkoG., MaliyovI., TrusovaV., MizuguchiC., SaitoH., KinnunenP. (2016) Combined thioflavin T-Congo red fluorescence assay for amyloid fibril detection. Methods and Applications in Fluorescence, 4, 034010.
29.
GodaS., TakanoK., YamagataY., NagataR., AkutsuH., MakiS., NambaK., YutaniK. (2000) Amyloid protofilament formation of hen egg lysozyme in highly concentrated ethanol solution. Protein Science, 9, 369–375.
30.
BhatS.A., BanoB. (2014) Conformational behaviour and aggregation of chickpea cystatin in trifluoroethanol: Effects of epicatechin and tannic acid. Archives of Biochemistry and Biophysics, 562, 51–61.
31.
FaziliN.A., NaeemA. (2015) Anti-fibrillation potency of caffeic acid against an antidepressant induced fibrillogenesis of human α-synuclein: Implications for Parkinson's disease. Biochimie, 108, 178–185.
32.
WaterhouseA.L. (2002) Determination of Total Phenolics. In: Current Protocols in Food Analytical Chemistry; John Wiley and Sons, I1.1.1–I1.1.8.
33.
ChaturvediS.K., AlamP., KhanJ.M., SiddiquiM.K., KalaiarasanP., SubbaraoN., AhmadZ., KhanR.H. (2015) Biophysical insight into the anti-amyloidogenic behavior of taurine. International Journal of Biological Macromolecules, 80, 375–384.
