Profiling of Flavonols in Seeds and Sprouts of Luffa cylindrica

Seeds of Luffa cylindrica (Luffa) have been considered as agricultural wastes. However, we hypothesized that the seeds and its sprouts may provide bioactive components that could provide health benefits for humans. The current study profiled the bioactive components in both seeds and sprouts of Luffa by using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MSn). Apigenin was identified as a major component in the seeds of Luffa, with a concentration of 2.89 mg from 1 g fresh weight. The bioactive components in the sprouts were myricetin, luteolin, and quercetin, with concentrations of 32.4, 12.5, and 32.5 μg from 1 g fresh weight, respectively. Apigenin metabolites, such as apigenin-glucuronic acid and apigenin-acetyl glucuronic acid, were also identified in the sprouts. This implied that apigenin in the seeds, when sprouting, was changed to other flavonols having a flavone backbone. Results from the current study suggest that both seeds and sprouts of Luffa could be a bio-resource for health-promoting food materials.

Profiling of flavonols in seeds and sprouts of Luffa cylindrical

Seeds of Luffa cylindrica (Luffa) have been considered as agricultural wastes. However, we hypothesized that the seeds and its sprouts may provide bioactive components that could provide health benefits for humans. The current study profiled the bioactive components in both seeds and sprouts of Luffa by using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MSn). Apigenin was identified as a major component in the seeds of Luffa, with a concentration of 2.89 mg from 1 g fresh weight. The bioactive components in the sprouts were myricetin, luteolin, and quercetin, with concentrations of 32.4, 12.5, and 32.5 μg from 1 g fresh weight, respectively. Apigenin metabolites, such as apigenin-glucuronic acid and apigenin-acetyl glucuronic acid, were also identified in the sprouts. This implied that apigenin in the seeds, when sprouting, was changed to other flavonols having a flavone backbone. Results from the current study suggest that both seeds and sprouts of Luffa could be a bio-resource for health-promoting food materials.

Smilax China root extract detoxifies nicotine by reducing reactive oxygen species and inducing CYP2A6

Resveratrol has a beneficial effect of lowering reactive oxygen species (ROS) and reduces cellular oxidative stress. We hypothesized that ethanol extract of Smilax china root (EESC) rich in resveratrol (RES) and oxyresveratrol (OXY) could reduce ROS caused by nicotine and promoting nicotine turnover by induction of CYP2A6. The amount of cotinine converted from nicotine was quantified by the direct barbiturate assay method. Expression of CYP2A6 was unregulated by RES, OXY, or EESC, respectively. Pretreatment of RES (50, 100, and 250 μM), OXY (50, 100, and 250 μM), and RES+OXY (50 and 100 μM) inhibited cytotoxicity and ROS production caused by nicotine in a dose-dependent manner. EESC pretreatment (1.8 mg/mL) increased cell viability by 1.5-fold higher than the control (nicotine only), and lowered cellular ROS levels. A significant amount of the conversion of nicotine to cotinine was observed in EESC pretreatment by CYP2A6 induction in HepG2 cells. These results suggested that hepatic induction of CYP2A6 and ROS reduction by EESC activate nicotine metabolism and reduce cellular oxidative stress.

PRACTICAL APPLICATION

Nicotine exposure due to smoking is very concerning because it is the major factor for lung diseases and cardiovascular disorders. It is necessary to examine natural ingredients that can detoxify from nicotine to cotinine as well as neutralize free radicals induced from nicotine. Results from the current study suggest potential applications of Smilax china root for detoxification of nicotine in the food industry.

Fermentation of Smilax china root by Aspergillus usami and Saccharomyces cerevisiae promoted concentration of resveratrol and oxyresveratrol and the free-radical scavenging activity

BACKGROUND

Smilax china root, which is rich in resveratrol and oxyresveratrol, has been used as emergency foods as well as folk medicine. This study investigated changes in concentration of bioactive components and the free-radical scavenging capacity of Smilax china root during fermentation by Aspergillus usami and Saccharomyces cerevisiae.

RESULTS

Resveratrol, oxyresveratrol and piceid were quantified as major constituents in Smilax china root by using UPLC-ESI-MS. The concentration of oxyresveratrol and resveratrol remarkably increased through fermentation and the transformation of piceid to resveratrol. Its concentration in 4% Smilax china root was 1.16-2.95 times higher than that of a 2% preparation throughout fermentation. The vitamin C equivalent antioxidant capacity of 2% Smilax china root was 1.51-1.91 times higher than that of 4% Smilax china root during fermentation. Meanwhile, ABTS free-radical scavenging capacity was enhanced up to 95.07 and 99.35% for 2% and 4% Smilax china root, respectively.

CONCLUSION

Results from our study propose that bioactive components in Smilax China root were highly extracted by fermentation followed by saccharification and ethanol production, resulting in enhanced free-radical scavenging capacity. © 2013 Society of Chemical Industry.

Digestive recovery of sulfur-methyl-L-methionine and its bioaccessibility in Kimchi cabbages using a simulated in vitro digestion model system

BACKGROUND

Sulfur-methyl-L-methionine (SMM) has been known to provide various biological functions such as radical scavenging effect, inhibition of adipocyte differentiation, and prevention of gastric mucosal damage. Kimchi cabbages are known to be a major food source providing SMM but its bioaccessibility has not been studied. The objective of current study was to determine both the digestive stability of SMM and the amount released from Kimchi cabbages under a simulated in vitro digestion model system.

RESULTS

The in vitro digestion model system simulating a human gastrointestinal tract was carried out for measuring digestive recovery and bioaccessibility of SMM. SMM was quantified by using high-performance liquid chromatography with a fluorescence detector. Recovery of an SMM standard after digestion was 0.68 and 0.65% for fasted and fed conditions, respectively, indicating that the digestive stability of the SMM standard was not affected by dietary energy or co-ingested food matrix. The SMM standard was also significantly stable in acidic pH (P < 0.05). The bioaccessibility of SMM from Kimchi cabbages was measured under a fasted condition, resulted in 8.83, 14.71 and 10.88%, for salivary, gastric and small intestinal phases, respectively.

CONCLUSION

Results from our study suggest that SMM from Kimchi cabbages, a component of food sources, is more bioavailable than SMM by itself.

Effect of hydroxypropyl methyl cellulose phthalate coating on digestive stability and intestinal transport of green tea catechins

BACKGROUND

The purpose of this study was to investigate the effect of hydroxypropyl methyl cellulose phthalate (HPMCP) coating on the digestive stability and intestinal transport of green tea catechins (GTCs).

METHODS

Two types of HPMCP coating were prepared: one type with size smaller than 500 μm (S-HPMCP) and the other with size larger than 500 μm (L-HPMCP). An in vitro gastrointestinal model system coupled with Caco-2 cells was used for estimating the bioavailability of GTCs. Ultraperformance liquid chromatography with a photodiode array detector was performed to analyze GTCs.

RESULTS

The digestive stability of GTCs was enhanced up to 33.73% and 35.28% for S-HPMCP and L-HPMCP, respectively. Intestinal transport of the GTCs was increased to 22.98% and 23.23% for S-HPMCP and L-HPMCP, respectively. Overall, the bioavailability of GTCs increased by 4.08 and 11.71 times for S-HPMCP and L-HPMCP, respectively.

CONCLUSION

The results of this study confirm that coating with HPMCP could be a way to improve the digestive stability and intestinal transport of GTCs.

Determination of cyanogenic compounds in edible plants by ion chromatography

Cyanogenic glycosides are HCN-producing phytotoxins; HCN is a powerful and a rapidly acting poison. It is not difficult to find plants containing these compounds in the food supply and/or in medicinal herb collections. The objective of this study was to investigate the distribution of total cyanide in nine genera (Dolichos, Ginkgo, Hordeum, Linum, Phaseolus, Prunus, Phyllostachys, Phytolacca, and Portulaca) of edible plants and the effect of the processing on cyanide concentration. Total cyanide content was measured by ion chromatography following acid hydrolysis and distillation. Kernels of Prunus genus are used medicinally, but they possess the highest level of total cyanide of up to 2259.81 CN⁻/g dry weight. Trace amounts of cyanogenic compounds were detected in foodstuffs such as mungbeans and bamboo shoots. Currently, except for the WHO guideline for cassava, there is no global standard for the allowed amount of cyanogenic compounds in foodstuffs. However, our data emphasize the need for the guidelines if plants containing cyanogenic glycosidesare to be developed as dietary supplements.

Inhibitory Effects of Ethyl Acetate-Soluble Fraction from Morus alba on Lipid Accumulation in 3T3-L1 Cells

Fruits of mulberry ( Morus alba) have been widely used for therapeutic purposes in Asian countries for centuries. Treatment of 3T3-L1 cells with ethanolic extracts of M. alba decreased adipocyte differentiation at 100 μg/mL by 18.6%. Treatment suppressed mRNA levels of PPARγ and C/EBPα expression in 3T3-L1 cells. However, the extract did not change free glycerol release from mature adipocytes. Thus, M. alba inhibited lipid accumulation by regulating transcription factors in 3T3-L1 adipocytes without a lipolytic effect. Among the soluble- fractions, the ethyl acetate-soluble fraction had the highest anti-adipogenic effects on 3T3-L1 cells. This fraction decreasing intracellular lipid accumulation by 38.5% in response to treatment with 100 μg/mL. In addition, HPLC analysis of the ethyl acetate-soluble fraction of M. alba contained 167.7 μM of protocatechulic acid in 1 mg/mL of fraction, which inhibited lipid accumulation by 44.8% in response to treatment with 100 μM. From these results, M. alba is a possible candidate for regulating lipid accumulation in obesity.

Inhibitory effects of ethyl acetate-soluble fraction from morus alba on lipid accumulation in 3T3-L1 cells

Fruits of mulberry (Morus alba) have been widely used for therapeutic purposes in Asian countries for centuries. Treatment of 3T3-L1 cells with ethanolic extracts of M. alba decreased adipocyte differentiation at 100 microg/mL by 18.6%. Treatment suppressed mRNA levels of PPARgamma and C/EBPalpha expression in 3T3-L1 cells. However, the extract did not change free glycerol release from mature adipocytes. Thus, M. alba inhibited lipid accumulation by regulating transcription factors in 3T3-L1 adipocytes without a lipolytic effect. Among the soluble- fractions, the ethyl acetate-soluble fraction had the highest antiadipogenic effects on 3T3-L1 cells. This fraction decreasing intracellular lipid accumulation by 38.5% in response to treatment with 100 microg/mL. In addition, HPLC analysis of the ethyl acetate-soluble fraction of M. alba contained 167.7 microM of protocatechulic acid in 1 mg/mL of fraction, which inhibited lipid accumulation by 44.8% in response to treatment with 100 microM. From these results, M. alba is a possible candidate for regulating lipid accumulation in obesity.

Green tea formulations with vitamin C and xylitol on enhanced intestinal transport of green tea catechins

The effect of green tea formulated with vitamin C and xylitol on intestinal cell transport of gallated and nongallated catechin was studied. The transport of catechins from both apical to basolateral and basolateral to apical directions was measured. The effect of vitamin C (4, 10, 20 ppm), xylitol (11, 27.5, 55 ppm), and combinations of both on the intestinal transport rate of catechins was examined. The efflux value (Pb→a/Pa→b) of (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), (-)-epicatechin (EC), and (-)-epicatechin gallate (ECG) was 0.26, 0.22, 1.22, and 0.17, respectively, indicating that EC appeared to be less absorbed compared with other catechins. The addition of xylitol (11, 27.5, 55 ppm) and vitamin C (4, 10, 20 ppm) and in combination enhanced transport rate of nongallated catechins such as EC and EGC. For EC, vitamin C was revealed to be the most effective on intestinal transport, implying the inhibition of the efflux transport mechanism of EC. Intestinal transport of gallated catechins significantly increased from catechins formulated with vitamin C and xylitol in a dose-dependent manner compared to the catechin-only formulation. Results provide a potential strategy to enhance the delivery and bioavailability of catechins in humans by modulating green tea formulation with vitamin C and xylitol.

Protective effect of chlorophyllin and lycopene from water spinach extract on cytotoxicity and oxidative stress induced by heavy metals in human hepatoma cells

The purpose of this study was to examine the inhibitory effects of ethanol extract of water spinach (EEWS) containing chlorophyll and lycopene on cytotoxicity and oxidative stress in liver induced by heavy metals. The (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT assay and dichlorofluorescein (DCF) assay were conducted to measure cytotoxicity and inhibition of reactive oxygen species (ROS), respectively. Cytotoxicity was prevented at a concentration of 11.7 mg/L of EEWS. Both sodium copper chlorophyllin (SCC) and lycopene in EEWS were identified by ultraperformance liquid chromatography-photodiode array-electrospray ionization-mass spectroscopy (UPLC-PDA-ESI-MS/MSn) as major components at m/z 722.64 and 535.45, respectively. The concentrations of SCC and lycopene were 0.12 and 0.04 mg from 100 g of dried powder, respectively. Approximately 99% cytotoxicity induced by Cd was inhibited by EEWS. However, the inhibitory effect attributed to generation of ROS was similar with SCC, lycopene, and EEWS. Our results indicated that EEWS was effective in reducing cytotoxicity and oxidative stress produced by heavy metals in a HepG2 cell. Data suggest that the possible mechanism underlying the preventive action of SCC might be associated with diminished absorption of metal ions by chelating and blocking metal-mediated generation of ROS, while lycopene effects may be attributed to its high number of conjugated dienes that act as most potent singlet oxygen quenchers.

Metabolite profiling of Cheonggukjang, a fermented soybean paste, inoculated with various Bacillus strains during fermentation

Metabolite profiling of Cheonggukjang inoculated with different Bacillus strains including Bacillus amyloliqueciens CH86-1, Bacillus licheniformis 58, and Bacillus licheniformis 67 during fermentation, was performed using gas chromatography-time of flight-mass spectrometry after derivatization, combined with multivariate statistical analysis. A total of 20 amino acids, 10 sugars, five sugar alcohols, and seven organic acids were identified in three Cheonggukjang samples. With fermentation time, most of the amino acids showed increasing amounts. On the other hand, most of the sugars including sucrose, fructose, and glucose decreasing patterns, and the amounts of organic acids varied. In order to observe differences in metabolites with fermentation time and inoculated Bacillus strains, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were carried out, respectively. On PCA plots, some sugars and organic acids including sucrose, fructose, glucose, mannose, succinic acid, and malonic acid, as well as most of the amino acids, contributed mainly to differentiation of the Cheonggukjang samples fermentation time. On the other hand, on PLS-DA, mannose, xylose, glutamic acid, and proline were mainly responsible for differentiating the Cheonggukjang among into various inoculated strains.

Metabolite profiling of doenjang, fermented soybean paste, during fermentation

BACKGROUND

A fermented soybean paste known as doenjang is a traditional fermented food that is widely consumed in Korea. The quality of doenjang varies considerably by its basic ingredients, species of microflora, and fermentation process. The classification of predefined metabolites (e.g. amino acids, organic acids, sugars and sugar derivatives, and fatty acids) in doenjang samples according to fermentation was performed by using GC-FID and GC-MS data sets with the application of a multivariate statistical method.

RESULTS

The predominantly produced amino acids included alanine, valine, leucine, isoleucine, proline, glutamine, phenylalanine and lysine, showing remarkable increases in amounts during the later stages of fermentation. Carbonic acid, citric acid, lactic acid and pyrogultamic acid were identified as the major organic acids. Significant amounts of erythrose, xylitol, inositol and mannitol were detected during fermentation. Regarding fatty acids, relatively higher amounts of palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were found in the doenjang at each fermentation time point. Principal component analysis (PCA) successfully demonstrated changes in composition patterns as well as differences in non-volatile metabolites according to fermentation period.

CONCLUSION

A set of metabolites could be determined representing the quality of doenjang during fermentation, and which might also be correlated with taste ingredients, flavour, nutrition, and physiology activities that are claimed to be dependent on the quality control of commercial doenjang.

Effect of Evodiae fructus extracts on gene expressions related with alcohol metabolism and antioxidation in ethanol-loaded mice

The effects of Evodiae fructus on alcohol concentration in blood plasma and the relative expression of alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), Cu-Zn superoxide dismutase (Cu-Zn SOD), glutathione peroxidase type 5 (GPX5), and catalase (CAT) in mice were assessed 1, 2, 3, and 4h after acute alcohol consumption. Evodiae fructus extracts (2.5, 5, and 10 mL/kg-bw), a commercial hangover removal drug (2.5, 5, and 10 mL/kg-bw), and saline solution, referred to as treatment, positive control, and negative control group, respectively, were orally given at the same time as alcohol administered to mice (20% and 40% concentration). Alcohol concentrations were the lowest in all of the Evodiae fructus treatment groups, as well as one (10 mL/kg-bw) of the positive control groups, 4h after ethanol exposure (0-5mg/dL and 60-110 mg/dL for 20% and 40% ethanol-loaded mice, respectively). Overall, the relative expression of ADH and Zn-Cu SOD were higher in treatment groups than in positive controls; whereas, the relative expression of GPX5 was higher in positive control groups than in treatment groups. The relative expression of ALDH and CAT was unchanged between treatments and positive controls. This study suggests that Evodiae fructus extracts can be used as a possible therapy for alcohol-induced hangover symptoms by stimulating the expression of hepatic alcohol metabolizing and antioxidant enzymes.

Analysis of mercury in sportfish tissue by thermal decomposition, amalgamation/atomic absorption spectrophotometry

Sportfish samples (n = 133) that originated from Indiana waters were analyzed for total mercury using inductively coupled plasma/mass spectrometry (ICP/MS) and thermal decomposition, amalgamation/atomic absorption spectrophotometry (TDA/ AAS). Total mercury concentrations obtained by the two methods were not significantly different (P > 0.05). The correlation coefficient for total mercury obtained for the two methods was 0.94. The limit of detection using TDA/AAS was 0.1 ppm. TDA/AAS is a preferred technique for the analysis of total mercury in fish tissue because it is rapid (6 min per sample) and easy to use and requires little sample preparation.

Mercury and omega-3 fatty acids in retail fish sandwiches

Mercury and fatty acids were measured in fish sandwiches from six retail restaurant chains. Average mercury concentrations ranged from 5 to 132 ppb and were well below the Food and Drug Administration action level (1,000 ppb). The average concentrations of eicosapentaenoic acid plus docosahexaenoic acid ranged from 91 to 620 mg per sandwich. Consuming one or two fish sandwiches per week could result in the consumption of 2 to 40% of the reference dose for mercury for a 60-kg individual and would provide 18 to 126% of the adequate intake for eicosapentaenoic acid plus docosahexaenoic acid as recommended for a pregnant or lactating woman.

Prediction of PCB content in sportfish using semipermeable membrane devices (SPMDs)

Triolein-filled semipermeable membrane devices (SPMDs) were immersed at three locations along the St. Joseph River in northern Indiana for 30 days to see if the PCB content of fish from the same location could be predicted with this model device. Triolein from the SPMD's was analyzed for PCB using enzyme-linked immunosorbent assay (ELISA) and compared to residues detected in fish collected from the same locations. There was a significant difference (p < 0.05) in total PCB concentrations between SPMD samples. However, due to variability in PCB residues between species and low PCB residues in SPMDs, a direct correlation between PCBs in sportfish and SPMDs could not be determined.