Ken Kusakari

Dr. Ken Kusakari


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 November 2020 in Molecules
Verified
Journal Article
Open access
PDF file
Doaa AlsaadiDoaa Alsaadi
Doaa Alsaadi
Raju AedlaRaju Aedla
Raju Aedla
KKKen Kusakari
Ken Kusakari
FKFARUK KARAHAN
FARUK KARAHAN
Nazim SekerogluNazim Sekeroglu
Nazim Sekeroglu
TAKASHI WATANABETAKASHI WATANABE
TAKASHI WATANABE
The growth and quality of licorice depend on various environmental factors, including the local climate and soil properties; therefore, its cultivation is often unsuccessful. The current study investigated the key factors that affect the contents of bioactive compounds of Glycyrrhiza glabra L. root and estimated suitable growth zones from collection sites in the Hatay region of Turkey. The contents of three bioactive compounds (glycyrrhizic acid, glabridin, and liquiritin), soil factors (pH, soil bearing capacity, and moisture content), and geographical information (slope, aspect, curvature, elevation, and hillshade) were measured. Meteorological data (temperature and precipitation) were also obtained. An analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA) were performed on the data. The soil bearing capacity, moisture content, slope, aspect, curvature, and elevation of the study area showed statistically significant effects on the glycyrrhizic acid and liquiritin contents. A habitat suitability zone map was generated using a GIS-based frequency ratio (FR) model with spatial correlations to the soil, topographical, and meteorological data. The final map categorized the study area into four zones: very high (15.14%), high (31.50%), moderate (40.25%), and low suitability (13.11%). High suitability zones are recommended for further investigation and future cultivation of G. glabra.

28 May 2019 in Natural Product Research
Verified
Journal Article
Closed access
KMKhine Zar Wynn Myint
Khine Zar Wynn Myint
TKTakumi Kido
Takumi Kido
KKKen Kusakari
Ken Kusakari
HDHari Prasad Devkota
Hari Prasad Devkota
TKTeppei Kawahara
Teppei Kawahara
TWTakashi Watanabe
Takashi Watanabe
Chemical isolation and bioactivity studies were conducted on the stamens of Mesua ferrea L., which are being used in a traditional skincare formulation in Myanmar. Rhusflavanone and mesuaferrone B were obtained as the main biflavonoids together with lupeol, five common flavonoids, and five phenolic compounds. After being identified by NMR and other spectroscopic analyses, these compounds were evaluated for their 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging, human leukocyte elastase inhibitory, and mushroom tyrosinase inhibitory activities. The two biflavonoids exhibited strong inhibitory activities against elastase and tyrosinase, but low DPPH-radical scavenging activities. The contents of rhusflavanone and mesuaferrone B in the stamens were 0.35 ± 0.04% and 0.55 ± 0.06%, respectively. Moreover, lupeol was considered to be a cosmetically important component of the stamens because of its high content and strong elastase inhibitory activity. Rhusflavanone was reported to be isolated from M. ferrea for the first time.

20 February 2024 in Molecules
Verified
Journal Article
Open access
PDF file
RURei Uranishi
Rei Uranishi
Raju AedlaRaju Aedla
Raju Aedla
Doaa AlsaadiDoaa Alsaadi
Doaa Alsaadi
DWDongxing Wang
Dongxing Wang
KKKen Kusakari
Ken Kusakari
TAKASHI WATANABETAKASHI WATANABE
TAKASHI WATANABE
The leaves of Chrysanthemum indicum L. are known to have various bioactive compounds; however, industrial use is extremely limited. To overcome this situation by producing high-quality leaves with high bioactive content, this study examined the environmental factors affecting the phytochemical content and antioxidant activity using C. indicum leaves collected from 22 sites in Kochi Prefecture, Japan. Total phenolic and flavonoid content in the dry leaves ranged between 15.0 and 64.1 (mg gallic acid g−1) and 2.3 and 11.4 (mg quercetin g−1), while the antioxidant activity (EC50) of the 50% ethanol extracts ranged between 28.0 and 123.2 (µg mL−1) in 1,1-Diphenyl-2-picrylhydrazyl radical scavenging assay. Among the identified compounds, chlorogenic acid and 1,5-dicaffeoylquinic acid were the main constituents in C. indicum leaves. The antioxidant activity demonstrated a positive correlation with 1,5-dicaffeoylquinic acid (R2 = 0.62) and 3,5-dicaffeoylquinic acid (R2 = 0.77). The content of chlorogenic acid and dicaffeoylquinic acid isomers varied significantly according to the effects of exchangeable magnesium, cation exchange capacity, annual temperature, and precipitation, based on analysis of variance. The habitat suitability map using the geographical information system and the MaxEnt model predicted very high and high regions, comprising 3.2% and 10.1% of the total area, respectively. These findings could be used in future cultivation to produce high-quality leaves of C. indicum.