Optimizing the ultrasound-assisted deep eutectic solvent extraction of flavonoids in common buckwheat sprouts.

In this study, deep eutectic solvents (DESs) coupled with ultrasound-assisted extraction (UAE) were evaluated and optimized for the extraction of major flavonoids from common buckwheat sprouts. Initially, 18 different choline chloride (CC)-based DESs were evaluated as potential extraction solvents, and 80% CCTG (CC-based DES composed of triethylene glycol and 20 vol% water) extracted significantly higher (p < 0.05) amounts of flavonoids than other DESs studied. The extraction efficiency of 80% CCTG was even higher (p < 0.05) than that of methanol for the extraction of vitexin and quercetin-3-O-robinobioside. Procedure using 80% CCTG and UAE were optimized; an extraction temperature of 56 °C and extraction time of 40 min were considered optimal. The optimized extraction procedure was reliable and efficient for the extraction of major flavonoids from common buckwheat sprouts. In addition, flavonoids could be efficiently recovered from DES extracts with high recovery yields (>97%) by using a C18 solid-phase extraction.

Leaf extracts from Dendropanax morbifera Léveille mitigate mercury-induced reduction of spatial memory, as well as cell proliferation, and neuroblast differentiation in rat dentate gyrus.

BACKGROUND: The brain is susceptible to methylmercury toxicity, which causes irreversible damage to neurons and glia and the leaf extract Dendropanax morbifera Léveille (DML) has various biological functions in the nervous system. In this study, we examined the effects of DML on mercury-induced proliferating cells and differentiated neuroblasts. METHODS: Dimethylmercury (5 µg/kg) and galantamine (5 mg/kg) was administered intraperitoneally and/or DML (100 mg/kg) was orally to 7-week-old rats every day for 36 days. One hour after the treatment, novel object recognition test was examined. In addition, spatial probe tests were conducted on the 6th day after 5 days of continuous training in the Morris swim maze. Thereafter, the rats were euthanized for immunohistochemical staining analysis with Ki67 and doublecortin and measurement for acetylcholinesterase (AChE) activity. RESULTS: Dimethylmercury-treated rats showed reduced discrimination index in novel object recognition test and took longer to find the platform than did control group. Compared with dimethylmercury treatment alone, supplementation with DML or galatamine significantly ameliorated the reduction of discrimination index and reduced the time spent to find the platform. In addition, the number of platform crossings was lower in the dimethylmercury-treated group than in controls, while the administration of DML or galantamine significantly increased the number of crossings than did dimethylmercury treatment alone. Proliferating cells and differentiated neuroblasts, assessed by Ki67 and doublecortin immunohistochemical staining was significantly decreased in the dimethylmercury treated group versus controls. Supplementation with DML or galantamine significantly increased the number of proliferating cells and differentiated neuroblasts in the dentate gyrus. In addition, treatment with dimethylmercury significantly increased AChE activity in hippocampal homogenates, while treatment with dimethylmercury+DML or dimethylmercury+galantamine significantly ameliorated this increase. CONCLUSIONS: These results suggest that DML may be a functional food that improves dimethylmercury-induced memory impairment and ameliorates dimethylmercury-induced reduction in proliferating cells and differentiated neuroblasts, and demonstrates corresponding activation of AChE activity in the dentate gyrus.

Metabolomics Analysis of the Lipid-Regulating Effect of Allium hookeri in a Hamster Model of High-Fat Diet-Induced Hyperlipidemia by UPLC/ESI-Q-TOF Mass Spectrometry.

Hyperlipidemia is a risk factor for atherosclerotic cardiovascular disease and is a major public health concern. Allium hookeri (AH) is an Allium species containing high levels of bioactive organosulfur compounds such as methiin and cycloalliin. AH exerts hypolipidemic effects in animals fed a high-fat diet. However, there exists little information on the mechanisms underlying these effects. To address this issue, we used a metabolomic approach based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry to identify factors mediating the lipid-lowering effects of AH. Principal component and partial least-squares discriminant analyses of serum metabolome profiles revealed 25 metabolites as potential biomarkers for the effects of AH on lipid levels. These compounds were predominantly phospholipids, including phosphatidylcholines (PCs), lysoPCs, and lysophosphatidylethanolamines. Glycerophospholipid metabolism was identified as a significantly enriched pathway. These results provide mechanistic insight into the antihyperlipidemic effects of AH and evidence for its efficacy as a therapeutic agent.

Comparative studies of bioactive organosulphur compounds and antioxidant activities in garlic (Allium sativum L.), elephant garlic (Allium ampeloprasum L.) and onion (Allium cepa L.).

We evaluated organosulphur compounds in Allium vegetables, including garlic, elephant garlic and onion, using high-performance liquid chromatography. Among organosulphur compounds, elephant garlic had considerable γ-glutamyl peptides, and garlic had the highest alliin content. Onion had low level of organosulphur compounds than did elephant garlic and garlic. In addition, antioxidant capacities were evaluated by oxygen radical absorbance capacity (ORAC) values and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay. The results showed that garlic had the highest antioxidant capacity, followed by elephant garlic and onion. Furthermore, a positive correlation was observed between antioxidant activities and organosulphur compounds (R > 0.77). Therefore, our results indicate that there was a close relationship between antioxidant capacity and organosulphur compounds in Allium vegetables.

Development and Method Validation of Analysis of Urushiol in Sumac and Food Ingredients in Korea.

This study developed an analytical method to determine the urushiol content in sap and several foods. The full process for urushiol analysis consists of extraction, trimethylsilyl silylation, analysis, and identification via GC-MS, with each step optimized to attain the required accuracy and precision. Urushiol was separated from sap via liquid-liquid extraction and was derivatized via silylation. The components were analyzed using a polar capillary column and identified using GC-MS. The deviations of relative retention times and retention time windows were within 0.001 and 0.02 min, which satisfied the criteria of 0.06 and 0.03 min, respectively. The response of the urushiol standards tested was found to be linear in the investigated concentration range, with a correlation coefficient of 0.998. The LODs were between 1.74 and 2.67 µg/mL.

Comparison of Anti-Inflammatory Effects of Flavonoid-Rich Common and Tartary Buckwheat Sprout Extracts in Lipopolysaccharide-Stimulated RAW 264.7 and Peritoneal Macrophages.

Buckwheat sprouts have been widely consumed all around world due to their great abundance of bioactive compounds. In this study, the anti-inflammatory effects of flavonoid-rich common buckwheat sprout (CBS) and tartary buckwheat sprout (TBS) extracts were evaluated in lipopolysaccharide- (LPS-) stimulated RAW 264.7 murine macrophages and primary peritoneal macrophages from male BALB/c mice. Based on the reversed-phase HPLC analysis, the major flavonoids in CBS were determined to be C-glycosylflavones (orientin, isoorientin, vitexin, and isovitexin), quercetin-3-O-robinobioside, and rutin, whereas TBS contained only high amounts of rutin. The TBS extract exhibited higher inhibitory activity as assessed by the production of proinflammatory mediators such as nitric oxide and cytokines including tumor necrosis factor-α, interleukin- (IL-) 6, and IL-12 in LPS-stimulated RAW 264.7 macrophages than CBS extract. In addition, TBS extract suppressed nuclear factor-kappa B activation by preventing inhibitor kappa B-alpha degradation and mitogen-activated protein kinase phosphorylation in LPS-stimulated RAW 264.7 macrophages. Moreover, the TBS extract markedly reduced LPS-induced cytokine production in peritoneal macrophages. Taken together, these findings suggest that TBS extract can be a potential source of anti-inflammatory agents that may influence macrophage-mediated inflammatory disorders.

Essential oils from two Allium species exert effects on cell proliferation and neuroblast differentiation in the mouse dentate gyrus by modulating brain-derived neurotrophic factor and acetylcholinesterase.

BACKGROUND: In the present study, we investigated the effects of oil products from two Allium species: Allium sativum (garlic) and Allium hookeri (Chinese chives) on cell proliferation and neuroblast differentiation in the mouse dentate gyrus. METHODS: Using corn oil as a vehicle, the essential oil from garlic (10 ml/kg), or Chinese chives (10 ml/kg) was administered orally to 9-week-old mice once a day for 3 weeks. One hour following the last treatment, a novel object recognition test was conducted and the animals were killed 2 h after the test. RESULTS: In comparison to the vehicle-treated group, garlic essential oil (GO) treatment resulted in significantly increased exploration time and discrimination index during the novel object recognition test, while Chinese chives essential oil (CO) reduced the exploration time and discrimination index in the same test. In addition, the number of Ki67-immunoreactive proliferating cells and doublecortin-immunoreactive neuroblasts significantly increased in the dentate gyrus of GO-treated animals. However, administration of CO significantly decreased cell proliferation and neuroblast differentiation. Administration of GO significantly increased brain-derived neurotrophic factor (BDNF) levels and decreased acetylcholinesterase (AChE) activity in the hippocampal homogenates. In contrast, administration of CO decreased BDNF protein levels and had no significant effect on AChE activity, compared to that in the vehicle-treated group. CONCLUSIONS: These results suggest that GO significantly improves novel object recognition as well as increases cell proliferation and neuroblast differentiation, by modulating hippocampal BDNF protein levels and AChE activity, while CO impairs novel object recognition and decreases cell proliferation and neuroblast differentiation, by reducing BDNF protein levels in the hippocampus.

UPLC/ESI-MS/MS analysis of compositional changes for organosulfur compounds in garlic (Allium sativum L.) during fermentation.

In this study, we used liquid chromatography coupled to ion trap mass spectrometry (MS) for the quantification of 11 organosulfur compounds and analysis of their compositional changes in garlic during fermentation using 3 different microbe strains. The calibration curves of all 11 analytes exhibited good linearity (R⩾0.995), and the mean recoveries measured at three concentrations were greater than 81.63% with relative standard deviations of less than 12.79%. Investigation of the compositional changes revealed that the γ-glutamyl peptides content in fermented blanched garlic reduced, whereas the content of the compounds in biosynthesis of S-allyl-l-cysteines from γ-glutamyl peptides increased significantly. Our results also indicated that starter cultures can be used selectively in the production of fermented garlic to increase the amounts of the desired organosulfur compounds.

Valerenic Acid Protects Against Physical and Psychological Stress by Reducing the Turnover of Serotonin and Norepinephrine in Mouse Hippocampus-Amygdala Region.

In a previous study, we demonstrated that a Valeriana officinalis extract could attenuate increases in serum corticosterone levels in a mouse model of physical and psychological stress. In addition, our results showed that the extract could modulate serotonin (5-HT) and norepinephrine (NE) turnover in the hippocampus and amygdala region. In this study, we intended to investigate the effects of valerenic acid (VA), the main component of V. officinalis extract, on corticosterone levels in serum in normal mice and monoamine turnover in hippocampus-amygdala homogenates in a mouse model of physical and psychological stress. To determine the minimum dose of VA for antianxiety effect, eight-week-old ICR mice were orally administered VA (0.2, 0.5, and 1.0 mg/kg/0.3 mL) once daily for 3 weeks to probe for immobility time and serum corticosterone levels. At a VA dose of 0.5 and 1.0 mg/kg, animals showed a decrease in the duration of immobility time and serum corticosterone levels. To confirm the antianxiety effect of VA, eight-week-old ICR mice received VA at a dose of 0.5 mg/kg, orally, once daily for 3 weeks, before being subjected to physical or psychological stress for 3 days, in a specially designed communication box, followed by estimation of levels of monoamines and their metabolites in the hippocampus-amygdala region. In conclusion, VA administration at 0.5 mg/kg can mitigate the physical and psychological stress response by decreasing the turnover of 5-HT to 5-hydroxyindoleacetic acid and NE to 3-methoxy-4-hydroxyphenylethyleneglycol sulfate in the hippocampus and amygdala.

Valeriana officinalis Extracts Ameliorate Neuronal Damage by Suppressing Lipid Peroxidation in the Gerbil Hippocampus Following Transient Cerebral Ischemia.

As a medicinal plant, the roots of Valeriana officinalis have been used as a sedative and tranquilizer. In the present study, we evaluated the neuroprotective effects of valerian root extracts (VE) on the hippocampal CA1 region of gerbils after 5 min of transient cerebral ischemia. Gerbils were administered VE orally once a day for 3 weeks, subjected to ischemia/reperfusion injury, and continued on VE for 3 weeks. The administration of 100 mg/kg VE (VE100 group) significantly reduced the ischemia-induced spontaneous motor hyperactivity 1 day after ischemia/reperfusion. Four days after ischemia/reperfusion, animals treated with VE showed abundant cresyl violet-positive neurons in the hippocampal CA1 region when compared to the vehicle or 25 mg/kg VE-treated groups. In addition, the VE treatment markedly decreased microglial activation in the hippocampal CA1 region 4 days after ischemia. Compared to the other groups, the VE100 group showed the lowest level of lipid peroxidation during the first 24 h after ischemia/reperfusion. In summary, the findings in this study suggest that pretreatment with VE has protective effects against ischemic injury in the hippocampal pyramidal neurons by decreasing microglial activation and lipid peroxidation.

Neuroprotective effects of Z-ajoene, an organosulfur compound derived from oil-macerated garlic, in the gerbil hippocampal CA1 region after transient forebrain ischemia.

The neuroprotective effects of two isomers (Z- and E-) of ajoene, a major compound in oil-macerated garlic products, against ischemic damage were investigated in the gerbil hippocampus. Vehicle (corn oil), Z- or E-ajoenes (25 mg/kg) was orally administered 30 min prior to the induction of transient forebrain ischemia by occlusion of the common carotid arteries for 5 min. One day after ischemia/reperfusion (I/R), I/R-induced hyperactivity significantly reduced in the E- and Z-ajoene-treated groups, compared to that in the vehicle-treated group 5 days after I/R, the number of cresyl violet-positive neurons in the E- and Z-ajoene-treated groups increased, compared to that in the vehicle-treated group. Reactive gliosis in the CA1 region of E- and Z-ajoene-treated groups reduced, compared to that in the vehicle-treated group. These neuroprotective effects were more prominent in animals treated with Z-ajoene, than in those treated with E-ajoene. In addition, Z-ajoene significantly decreased lipid peroxidation, as indicated by 4-hydroxy-2-nonenal levels in hippocampal homogenates, compared to that observed in the vehicle-treated group at a range of time points after I/R. These results suggested that Z-ajoene protected against I/R-induced delayed neuronal death and gliosis by reducing lipid peroxidation in the gerbil hippocampal CA1 region.

Effects of curcumin (Curcuma longa) on learning and spatial memory as well as cell proliferation and neuroblast differentiation in adult and aged mice by upregulating brain-derived neurotrophic factor and CREB signaling.

Aging is a progressive process, and it may lead to the initiation of neurological diseases. In this study, we investigated the effects of wild Indian Curcuma longa using a Morris water maze paradigm on learning and spatial memory in adult and D-galactose-induced aged mice. In addition, the effects on cell proliferation and neuroblast differentiation were assessed by immunohistochemistry for Ki67 and doublecortin (DCX) respectively. The aging model in mice was induced through the subcutaneous administration of D-galactose (100 mg/kg) for 10 weeks. C. longa (300 mg/kg) or its vehicle (physiological saline) was administered orally to adult and D-galactose-treated mice for the last three weeks before sacrifice. The administration of C. longa significantly shortened the escape latency in both adult and D-galactose-induced aged mice and significantly ameliorated D-galactose-induced reduction of cell proliferation and neuroblast differentiation in the subgranular zone of hippocampal dentate gyrus. In addition, the administration of C. longa significantly increased the levels of phosphorylated CREB and brain-derived neurotrophic factor in the subgranular zone of dentate gyrus. These results indicate that C. longa mitigates D-galactose-induced cognitive impairment, associated with decreased cell proliferation and neuroblast differentiation, by activating CREB signaling in the hippocampal dentate gyrus.

Validated HPLC method and temperature stabilities for oil-soluble organosulfur compounds in garlic macerated oil.

To enhance the utilization of garlic macerated oil as functional foods, oil-soluble organosulfur compounds were investigated using normal-phase high-performance liquid chromatography method. For analysis of compounds, it was simply extracted with 98% n-hexane in 2-propanol followed by sensitive and selective determination of all compounds. These method exhibited excellent linearity for oil-soluble organosulfur compounds with good coefficient (r > 0.999). Average recoveries were in the range of 80.23-106.18%. The limits of quantitation of oil-soluble organosulfur compounds ranged from 0.32 to 9.56 µg mL(-1) and the limits of detection were from 0.11 to 3.16 µg mL(-1). Overall, the precision of the results, expressed as relative standard deviation, ranged from 0.55 to 11.67%. The proposed method was applied to determining the contents of oil-soluble organosulfur compounds in commercial garlic macerated oils. Also, the stability of oil-soluble organosulfur compounds in garlic macerated oil were evaluated during 3 months of storage at four difference temperatures (4, 10, 25 and 35°C). The results showed the studied oil-soluble compounds in garlic macerated oil were stable at 4°C and relatively unstable at 35°C with varied extents degradation. Therefore, these validation data and temperature stability may be useful for quality evaluation of garlic macerated oils.