Antiallergic activities of shallot (Allium ascalonicum L.) and its therapeutic effects in allergic rhinitis.

BACKGROUND: Onion has antiallergic activity but lack of evidence for shallot. OBJECTIVE: To determine whether shallot owns similar antiallergic activity to onion and its therapeutic effects in allergic rhinitis when added to standard treatment. METHODS: In-vitro ß-hexosaminidase inhibitory activities of shallot was compared with onion on RBL-2H3 cells. In clinical study, a randomized, double-blind, placebo-controlled trial was performed. Sixteen AR patients were randomized equally into the controls who received cetirizine 10 mg once daily and placebo capsules for 4 weeks, and the treatment who received 3g of oral shallot per day (equivalent to 1 ½ bulbs) and cetirizine. Visual analog scores of overall symptoms (VAS), total nasal and ocular symptom scores (TNSS and TOSS), nasal airway resistance (NAR), and adverse events were assessed. RESULTS: Shallot extract at 200 µg/mL had an average ß-hexosaminidase inhibition rate of 97% while onion extract had 73%. HPLC chromatograms (λ = 290nm) of both plants showed nearly identical patterns of quercetin compounds, such as quercetin 3,4'-diglucoside, quercetin 4'-glucoside, and quercetin. After 4-week of treatment, 62.5% of patients in shallot group and 37.5% of patients in control group showed improvement of post-treatment VAS. TNSS were significantly reduced in both groups, however no difference between groups (P = 0.18). TOSS were significantly improved only in the shallot group (P = 0.01). Adverse events from shallot were not different from placebo. CONCLUSIONS: Shallot had antiallergic activity and similar quercetin compounds to onion. The shallot oral supplement and cetirizine was shown to improve the overall AR symptoms more than cetirizine alone.

A method for gaining a deeper insight into the aroma profile of olive oil.

Volatile compounds in food play a crucial role in affecting food quality and consumer preference, but the volatile compounds in olive oil are not fully understood due to the matrix effect of oil. The oiling-out assisted liquid-liquid extraction (OA-LLE), which we previously reported, is an effective method for isolating volatile compounds from edible oils with a strong matrix effect. However, when we apply OA-LLE to extra virgin olive oil (EVOO), the aromatic extracts contain non-volatile compounds such as pigments because of solvent-based extraction. Solvent-assisted flavor evaporation (SAFE) can remove such non-volatiles from extracts, but SAFE is affected by a matrix effect during distillation, resulting in a decrease in performance. By combining the advantages of OA-LLE and SAFE, we propose an effective approach, OA-LLE followed by SAFE (OA-LLE + SAFE), for extracting aroma compounds from EVOO. The "two assists" should help to better understand the native aroma profile of EVOO.

Oiling-out effect improves the efficiency of extracting aroma compounds from edible oil.

Volatile compounds in foods are a significant factor that affects food intake and preference. However, volatile components in edible oils are poorly understood due to a strong matrix effect. In this study, we developed a method of extracting volatile compounds from extra virgin coconut oil (EVCO) by means of oiling-out assisted liquid-liquid extraction (OA-LLE). Consequently, 44 aroma compounds were isolated and identified from only 5 g of EVCO. Various aroma compounds were detected in addition to δ-lactones. The ratio of the natural abundance of the enantiomers of δ-lactones in EVCO was also revealed. Compared with the conventional methods of solvent assisted flavor evaporation (SAFE) and head-space solid-phase micro extraction (HS-SPME), OA-LLE was able to isolate a wide range and large number of volatile compounds from EVCO without leaving oil residues. Therefore, isolating aroma compounds from edible oil based on the oiling-out effect should provide an innovative extraction method.

Rosmarinic acid and its ester derivatives for enhancing antibacterial, α-glucosidase inhibitory, and lipid accumulation suppression activities.

Rosmarinic acid (RA), commonly found in Nepetoidae subfamily of Lamiaceae family, possesses various biological activities. To expand its application, RA was modified by esterification with methyl (me), propyl (pro), and hexyl (hex) alcohols and then tested antibacterial, α-glucosidase inhibitory, and lipid accumulation suppression activities. Consequently, RA derivatives enhanced antibacterial activity, especially the RA-pro and RA-hex, which effectively inhibited the growth of Bacillus cereus rather than tannic acid, a natural antibacterial agent. RA-hex also inhibited α-glucosidase inhibitory activity greater than luteolin. By computational molecular docking, dihydroxyphenyl group and hexyl group were selected as essential groups for interaction with the active site of α-glucosidase through hydrogen bonding and hydrophobic interaction, contributing to the great inhibitory activity. Furthermore, RA-pro and RA-hex effectively suppressed lipid accumulation of 3T3-L1 cells, superior to EGCG, a well-known anti-obesity phytochemical. These biological effects of RA derivatives commonly attributed to hydrophobicity, hydrogen bonding, and steric bulkiness of the side chain. PRACTICAL APPLICATIONS: Rosmarinic acid (RA), a fundamental compound in the family Lamiaceae, is one of powerful naturally occurring antioxidants as well as other biological activities. Furthermore, its abundance in nature was also high in amount in the plant kingdom. So, natural RA can be one of possible natural resources for creating potent natural drugs and biologically useful substances after chemical modification. Studies on various biological activities may intensively expand usage and application of RA. In this study, RA was derivatized to corresponding ester such as methyl, propyl, and hexyl alcohols with higher hydrophobicity, and found great antibacterial, α-glucosidase inhibitory, and lipid accumulation suppression activities. RA-pro and RA-hex significantly suppressed lipid accumulation and cell differentiation. Therefore, RA derivatives with multiple biological activities have the potential to be applied in the food and pharmaceutical industries as food ingredients and supplements.

A fast and sensitive isocratic high performance liquid chromatography method for determination of guaraná (Paullinia cupana) flavan-3-ols.

Most methods for quantification of catechins in guaraná and other food matrices rely on lengthy gradients to resolve all peaks, and the analysis time for one sample is around 45-135 min. The present method is a fast, sensitive and simple HPLC-UV method, with a 16-minute isocratic run that deliver the high throughput needed to process a large number of samples without compromising the analyte stability. This method is suitable for the determination of catechins, procyanidins (up to degree of polymerisation 2) and caffeine in guaraná extracts, in vitro digesta, and Caco-2 cell permeates. The higher sensitivity was achieved by detection at 210 nm, after checking for the absence of interfering substances in the matrices. The method was validated and LODs of 0.019, 0.030, 0.028, 0.030, and 0.043 nmol/mL were achieved for catechin, epicatechin, procyanidin B1, procyanidin B2 and caffeine, respectively. Standard recovery at three different concentrations were within 97-109%. Intra- and inter-day variabilities (RSD) were both under 4%. •This is an isocratic HPLC-UV method for the quantification of flavan-3-ols from guaraná (Paullinia cupana), which is 3-8 times faster and >80 times sensitive than previously published methods using UV or diode array detectors.•It is cost-effective as it uses the widely available and affordable UV detector and consumes less solvent due the short analysis time.•With low LODs, fast sample preparation and the short analytical run, this method can be used for the quantification of flavan-3-ols and caffeine in guaraná extracts as well as guaraná in vitro digesta and its Caco-2 permeates.

Induction of G2/M arrest and apoptosis through mitochondria pathway by a dimer sesquiterpene lactone from Smallanthus sonchifolius in HeLa cells.

Dimer sesquiterpene lactones (SLs), uvedafolin and enhydrofolin, against four monomer SLs isolated from yacon, Smallanthus sonchifolius, leaf were the most cytotoxic substances on HeLa cells (IC50 values 2.96-3.17 µM at 24 hours). However, the cytotoxic mechanism of dimer SL has not been elucidated yet. Therefore, in this study, we clarified the in vitro cytotoxic mechanism of uvedafolin on the HeLa cells, and evaluated the cytotoxicity against NIH/3T3 cells which were used as normal cells. In consequence, the dimer SLs had low toxicity for the NIH/3T3 cells (IC50 4.81-4.98 µM at 24 hours) and then the uvedafolin mediated cell cycle arrest at the G2/M phase and induced apoptosis on the HeLa cells evidenced by appearance of a subG1 peak. Uvedafolin induced apoptosis was attributed to caspase-9 and caspase-3/7 activities. An effectively induced apoptosis pathway was demonstrated from mitochondria membrane potential change and cytochrome c release to cytosol. These results reveal that uvedafolin induced apoptosis via the mitochondria pathway. The present results indicate the potential of uvedafolin as a leading compound of new anticancer agents.

Survey of Thai Commercial Food Products That Have Been Reported to Contain No Wheat, Rye, Barley, or Gluten According to Their Labels.

Celiac disease (CD) and gluten-related disorders are significant health and social issues in Western countries, and CD individuals need to exclude gluten from their diets. The adverse health impacts of CD have extended to Asian countries in which CD was not a problem previously. Thai commercial food products that do not contain wheat, rye, barley, or gluten on their labels were surveyed as to whether they were suitable for CD individuals by examining the absence of gluten or the presence of gluten <20 ppm. In Thailand, ELISA tested for gluten content in 129 commercial food products that contained neither wheat, rye, barley, nor gluten on their labels. One hundred nineteen of these 129 products included <20 ppm gluten, and 10 products contained >20 ppm gluten. Surprisingly, four products showed gluten levels >1%. In these 10 products, wheat presence was confirmed by PCR analysis. Our survey suggests that CD individuals can consume most of the examined Thai food products, and the survey showed the potential of these Thai products as new diets for CD patients so as to expand the limited food choices from different food cultures, and ultimately to improve the quality of life for all CD individuals globally. The appropriate gluten management strategies need to be implemented by Thai food manufacturers to ensure accurate labeling and to protect the safety of consumers with CD.

Absorption, Metabolism, and Excretion by Freely Moving Rats of 3,4-DHPEA-EDA and Related Polyphenols from Olive Fruits (Olea europaea).

Absorption, metabolism, and excretion of 3,4-DHPEA-EDA, oleuropein, and hydroxytyrosol isolated from olive fruits were newly evaluated after oral and intravenous administration in freely moving rats cannulated in the portal vein, jugular vein, and bile duct. Orally administered 3,4-DHPEA-EDA, an important bioactive compound in olive pomace, was readily absorbed and metabolized to hydroxytyrosol, homovanillic acid, and homovanillyl alcohol, as shown by dose-normalized 4 h area under the curve (AUC0→4 h/Dose) values of 27.7, 4.5, and 4.2 µM·min·kg/µmol, respectively, in portal plasma after oral administration. The parent compound 3,4-DHPEA-EDA was not observed in the portal plasma, urine, and bile after oral and intravenous administration. Additionally, hydroxytyrosol, homovanillic acid, and homovanillyl alcohol in the portal plasma after oral administration of hydroxytyrosol showed 51.1, 22.8, and 7.1 µM·min·kg/µmol AUC0→4 h/Dose, respectively. When oleuropein, a polar glucoside, was injected orally, oleuropein in the portal plasma showed 0.9 µM·min·kg/µmol AUC0→4 h/Dose. However, homovanillic acid was detected from oleuropein in only a small amount in the portal plasma. Moreover, the bioavailability of hydroxytyrosol and oleuropein for 4 hours was 13.1% and 0.5%, respectively. Because the amount of 3,4-DHPEA-EDA in olive fruits is about 2-3 times greater than that of hydroxytyrosol, the metabolites of 3,4-DHPEA-EDA will influence biological activities.

New Sesquiterpene Lactone Dimer, Uvedafolin, Extracted from Eight Yacon Leaf Varieties (Smallanthus sonchifolius): Cytotoxicity in HeLa, HL-60, and Murine B16-F10 Melanoma Cell Lines.

Uvedafolin, 1, a new sesquiterpene lactone dimer, was isolated from the leaves of Smallanthus sonchifolius with five related compounds, 2-6, and their cytotoxicity was assessed against three tumor cell lines (HeLa, HL-60, B16-F10 melanoma). The stereostructure of 1 was newly elucidated by ESI-TOF-MS, 1D/2D NMR, and single-crystal X-ray diffraction. Dimers 1 and 2 had the most effective IC50 values, 0.2-1.9 µM, against the three tumor cell lines when compared with monomers 3-6 (IC50 values 0.7-9.9 µM) and etoposide (IC50 values 0.8-114 µM). The ester linkages of two sets of monomers, uvedalin, 5, and sonchifolin, 6, for 1, and enhydrin, 4, and sonchifolin, 6, for 2, as well as the acetyl group at the C-9 position, were essential for the high cytotoxicity. Dimers 1 and 2 would have potential as anticancer agents.

Analysis of the reaction products from micro-vial pyrolysis of the mixture glucose/proline and of a tobacco leaf extract:Search for Amadori intermediates.

Micro-vial pyrolysis (PyroVial) was used to study the production of compounds important for the aroma of heat-treated natural products such as tobacco. Firstly, a mixture of glucose and proline was pyrolyzed as model, as this sugar and amino acid are also abundant in tobacco leaf (Nicotiana tobacum L.). The pyrolysate was analyzed using headspace-GC­MS, liquid injection GC­MS and LC­MS. Next, micro-vial pyrolysis in combination with LC­MS was applied to tobacco leaf extract. Using MS deconvolution, molecular feature extraction and differential analysis it was possible to identify Amadori intermediates of the Maillard reaction in the tobacco leaf extract. The intermediate disappeared as was the case for 1-deoxy-1-prolino-ß-d-fructose or the concentration decreased in the pyrolysate compared to the original extract such as for the 1-deoxy-1-[2-(3-pyridyl)-1-pyrrolidinyl]-ß-d-fructose isomers indicating that Amadori intermediates are important precursors for aroma compound formation.

High antiallergic activity of 5,6,4'-trihydroxy-7,8,3'-trimethoxyflavone and 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone from eau de cologne mint (Mentha×piperita citrata).

The following compounds with higher antiallergic activities were isolated from eau de cologne mint leaves: 5,6,4'-trihydroxy-7,8-dimethoxyflavone (6), 5,6,4'-trihydroxy-7,8,3'-trimethoxyflavone (7), 5,6-dihydroxy-7,3',4'-trimethoxyflavone (8), 5,6-dihydroxy-7,8,3',4'-tetramethoxyflavone (9), and 5,6-dihydroxy-7,8,4'-trimethoxyflavone (10). The IC50 values of compounds 6-10 against RBL-2H3 cells were 6.7, 2.4, 5.6, 3.0, and 6.1µM. Compounds 7 and 9 (IC50 2.4µM and 3.0µM) had the highest antiallergic activities among the flavonoids previously reported. The amounts of 7, 9, and 10 isolated were fairly high, at 177.7mg/kg, 278.0mg/kg, and 179.7mg/kg in the mint, respectively. LD5 value (index of toxicity) and LD5/IC50 ratio of 7 and 9 indicate that the safety is greater than that of luteolin, a typical antiallergic substance. The extract containing powerful antiallergic flavones, 6-10 with higher hydrophobicity could be selectively separated from the extract containing luteolin and other flavonoid glycosides by partition with dichloromethane and water. Therefore, compounds 7 and 9 in mint, and the dichloromethane extract would be the most potent and preventive resources against type I allergy.

Antiallergic activity of rosmarinic acid esters is modulated by hydrophobicity, and bulkiness of alkyl side chain.

Methyl, propyl and hexyl esters of rosmarinic, caffeic and p-coumaric acids were tested for antiallergic activity, and rosmarinic acid propyl ester exhibited the greatest ß-hexosaminidase release suppression (IC50, 23.7 µM). Quadratic correlations between pIC50 and cLogP (r(2) = 0.94, 0.98, and 1.00, respectively) were observed in each acid ester series. The antiallergic activity is modulated by hydrophobicity, and alkyl chain bulkiness.

New technique to isolate anthocyanins from Delaware grapes by forming an aluminium complex using a Discovery DPA-6S.

An aluminium complex of crude Delaware grape anthocyanins, bearing an ortho-dihydroxyl group on the B ring and/or a p-coumaroyl group as an ester with flavocommelin, was formed and isolated by ethanol precipitation. Using a Discovery DPA-6S short column, selected anthocyanins were isolated to give cyanidin 3-glucoside (Cy3G, 48.2% yield with 95.2% purity) and cyanidin 3-(6-O-p-coumaroylglucoside) (Cy3-pC·G, 44.9% yield with 91.4% purity) from natural Delaware grape skin extracts without ODS-HPLC column chromatography. DPPH radical scavenging activity of the complex pigment was 3.4 ± 0.10 µmol TE/mg. Moreover, isolated pure anthocyanins from the complex pigment showed significantly higher DPPH radical scavenging activity [4.5 ± 0.08 µmol TE/mg (Cy3G) and 4.5 ± 0.04 µmol TE/mg (Cy3-pC·G), (p<0.05)].

Stimulation of phosphorylation of ERK and CREB by phellopterin and auraptene isolated from Citrusjunos.

Bioactive compounds from citrus fruits contribute many benefits to human health. Extracellular signal-regulated kinase (ERK) signaling plays an important role in the regulation of multiple cellular processes. Activation of the ERK-cAMP response element binding protein (CREB) signaling is required for long- term memory formation. In this study, auraptene, phellopterin, thymol, coniferyl alcohol 9-methyl ether and methyl ferulate were isolated from Citrus junos. Among the five compounds isolated, auraptene and phellopterin increased the phosphorylation of ERK and CREB. This study provides, to our knowledge, the first evidence that phellopterin potently stimulates the phosphorylation of ERK and CREB. Phellopterin could be a novel neuroprotective agent.

Secoiridoid type of antiallergic substances in olive waste materials of three Japanese varieties of Olea europaea.

2-Hydroxy-3-ethylidene-5-(methoxycarbonyl)-3,4-dihydro-2H-pyran-4-acetic acid 2-(3,4-dihydroxyphenyl)ethyl ester (3,4-DHPEA-EA) is a kind of secoiridoid first found in three Japanese olive pomaces: Mission, Lucca, and Manzanillo. These varieties showed high activity of 3,4-DHPEA-EA as an antiallergic active substance with IC50 at 33.5 ± 0.6 µg/mL. Because 3,4-DHPEA-EA was the most abundant among the active substances in the pomaces and the activity of 3,4-DHPEA-EA was greater than that of hydroxytyrosol and elenolic acid, 3,4-DHPEA-EA, which has the ester linkage of hydroxytyrosol and elenolic acid, should be essential for antiallergic activity. Although a trace amount (1.04 mg/kg) of luteolin in the pomace showed the highest antiallergic activity with IC50 at 0.752 ± 0.1 µg/mL, we concluded that the entire antiallergic effect derives from the abundance of 3,4-DHPEA-EA, especially in the green olive pomace of the Mission variety in October, which showed the highest level of 3,4-DHPEA-EA (5033 ± 118 mg/kg). Therefore, the Mission variety had the most effective antiallergy property.

Isolation techniques for anthocyanidin 3,5-diglucosides and their related chemicals using supramolecules technique, and two solid-phase extraction cartridges.

Isolation techniques for anthocyanidin 3,5-diglucosides and their derivatives from three types of supramolecular pigments were newly developed using two SPE (Discovery DPA-6S and DSC-SCX) cartridges. Initially, malonylawobanin from commelinin supramolecular complex yielded 79.5% with 85.7% purity using DPA-6S, while DSC-SCX gave a rather lower yield (62.5%) of malonylawobanin with high purity (90.8%). Delphinidin 3,5-diglucoside and awobanin from acidic hydrolysis of commelinin were easily separated using DPA-6S. Secondary, artificial Perilla supramolecules (reconstructed from Perilla crude pigment, flavocommelin and Mg(2+)) result in a high purity of a malonylshisonin and shisonin mixture (96.1%) with DSC-SCX. Finally, succinylcyanin, which is a component of protocyanin, yielded 64.3% with 86.1% purity using DPA-6S and 51.8% with 74.1% purity using DSC-SCX. Moreover, cyanidin 3,5-diglucoside yielded 43.4% with 97.0% purity using DPA-6S after partial acidic hydrolysis of protocyanin.

A new diterpene from Litsea cubeba fruits: structure elucidation and capability to induce apoptosis in HeLa cells.

A new diterpene, identified as (+)-6-(4-hydroxy-4-methyl-2-pentenoyl)-4,6-dimethyl-5-(3-methyl-2-butenyl)-1,3-cyclohexadienecarbaldehyde (1, cubelin), was isolated from a methanol extract of Litsea cubeba fruits by normal phase column chromatography and purified by preparative HPLC. The structure elucidation was conducted by spectroscopic methods (UV, IR, ESI-TOF-MS, 1-D and 2-D NMR). Cubelin exhibited activity against HeLa cell viability and proliferation. The cells also exhibited changes in nuclear morphology which are hallmarks of apoptotic cell death. The presence of cleaved caspase-3/-7, caspase-8 and caspase-9 in the cubelin treated population indicated the potential of the compound to induce apoptosis in HeLa cells via both intrinsic and extrinsic pathways.

Rosmarinic acid extract for antioxidant, antiallergic, and α-glucosidase inhibitory activities, isolated by supramolecular technique and solvent extraction from Perilla leaves.

Rosmarinic acid extract with potent biological activities was successfully isolated by supramolecular technique and solvent extraction from Perilla leaves. By the supramolecular complex which was formed from flavocommelin and Perilla leaf extract as initial materials, the supernatant containing rosmarinic acid was isolated. Rosmarinic acid extract (62.9 ± 4.5% purity) was partly purified by partitioning ethyl acetate and water. Rosmarinic acid extract exhibited high total phenolic content of 433.9 ± 58.6 µg/mg of gallic acid equivalent, effective DPPH radical scavenging activity (SC50 of 5.5 ± 0.2 µg/mL), antiallergic activity (IC50 of 52.9 ± 6.7 µg/mL), and α-glucosidase inhibitory activity (IC50 of 0.23 ± 0.01 mg/mL). Rosmarinic acid extract shows high potential for diabetes mellitus and allergy treatments by inhibiting α-glucosidase activity and measuring ß-hexosaminidase, related to life-style disease.

Isolation of bilberry anthocyanidin 3-glycosides bearing ortho-dihydroxyl groups on the B ring by forming an aluminum complex and their antioxidant activity.

Bilberry anthocyanin bearing an ortho-dihydroxyl group on the B ring was selectively isolated by complex formation with flavocommelin and aluminum ions (Al(3+)). The interaction between the anthocyanins, flavocommelin, and Al(3+) might have happened in a manner similar to rigid supramolecules, such as commelinin, protocyanin, and other complex pigments. Complex blue pigment (CP, 8.85 ± 0.26 mg) with Al(3+) was formed from 18.6 mg (15 µmol) of bilberry pigment, 18.2 mg (30 µmol, 2.0 equiv) of flavocommelin, and 0.03 mL of 0.5 M aluminum chloride aqueous solution (15 µmol, 1.0 equiv), yielding 36.5 ± 0.7% recovery of anthocyanins in the complex after precipitation by ethanol. Consequently, anthocyanins bearing ortho-dihydroxyl groups on the B rings (delphinidin 3-glycosides, cyanidin 3-glycosides, and petunidin 3-glycosides) predominating (98.0 ± 0.2%) in the complex were selectively isolated in a dose-dependent manner by the addition of Al(3+), increasing the antioxidative activity of the mixture of anthocyanins.

Effect of epoxides and α-methylene-γ-lactone skeleton of sesquiterpenes from yacon (Smallanthus sonchifolius) leaves on caspase-dependent apoptosis and NF-κB inhibition in human cercival cancer cells.

The present study investigated the cytotoxicity of enhydrin (1), uvedalin (2) and sonchifolin (3) in cervical cancer cells. We have found that SLs 1-3 in doses in range of 0.22-10 µM inhibited cell proliferation and induced apoptosis in both a dose- and time-dependent fashion. A significant cell death induction was supported by morphological studies. The apoptotic effect is associated with caspase-3/7 activation and NF-кB inhibition. Interestingly, enhydrin possessing two epoxide units was found to be the most cytotoxic compound. Therefore it can be assumed that number of epoxides and existence of α-methylene-γ-lactone moiety are essential for the acceleration of apoptosis.