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Cumulative light exposure, including electronic device radiation, may induce retinal pigment epithelium (RPE)-related retinal diseases, potentially mitigated by lutein. However, there is limited 3D RPE monolayer model to study the effect of phytochemicals on their activity and action mechanisms in vitro. Here, we present a method using a monolayer RPE tissue model on a 3D-printed polycaprolactone scaffold. Six-hour of phone screen light increased reactive oxygen species (ROS) in RPE cells, leading to oxidative stress, cytotoxicity, and inhibited metabolism. Pre-treating RPE cells (24 h) with 0.5 µM lutein reduced ROS levels and maintained viability under the same light exposure. Additionally, lutein demonstrated protective effects on crucial RPE functions, including phagocytosis and the retinal-blood barrier. This study underscores the importance of optimal lutein content in shielding RPE from phone screen light damage, and our model holds promise for evaluating the efficacy of antioxidants against light radiation.

Edible mushroom Antrodia cinnamomea is distinctive for its use in many health supplement products in relieving of diverse health-related conditions. A. cinnamomea is known for its rich array of bioactive secondary metabolites, predominantly terpenoids, that possess anti-inflammatory properties. Despite the abundance of these compounds, only some compounds have demonstrated notable anti-inflammatory activity. Moreover, there is a lack of established quality control methods specifically tailored to the active constituents of these products. Consequently, there is a great need for the development of precise and effective quality control methods for A. cinnamomea-based products, targeting their active components to ensure the consistency and reliability of these products in harnessing their anti-inflammatory potential. Herein we report a quantitative HPLC method for better evaluating the quality of A. cinnamomea based dietary supplements. Based on their bioactivities, we selected ten benchmark compounds, i. e. antcin K, (25S)-antcin H, (25R)-antcin H, (25R)-antcin C, (25S)-antcin C, (25R)-antcin A, 15α-acetyl-dehydrosulphurenic acid, versisponic acid D, dehydroeburicoic acid, and eburicoic acid and developed and validated a HPLC-UV method for quantification of these compounds simultaneously with high sensitivity, linearity and range, precision, and accuracy. Furthermore, we applied our method to quantify the commercially available A. cinnamomea containing supplements and found that the quality of these supplements varies greatly with only one product containing good amount of the active compounds. Our method provides a needed solution to quality control problem of the highly priced A. cinnamomea food and nutraceutical products that show great variety and inconsistency.

This study investigates freeze-dried okra seed flour (OSF) as a functional ingredient to attenuate postprandial blood glucose rise by creating lower glycemic index (GI) rice noodles. Secondary objectives are postprandial gut hormone responses, noodle satiety, and sensory evaluation. Twenty healthy individuals consumed control rice noodle (CON), 10 % okra seed fortified noodle (OKN), 20 % OKN and glucose reference drinks on separate visits. 20 % OKN significantly lowered the postprandial glucose and insulin peaks compared to CON. Compared to CON, there was a 20-point reduction of GI value for 20 % OKN to 64. All noodles produced similar responses in postprandial ghrelin and glucagon-like peptide-1 (GLP-1). OKN were found to be more satiating than control noodles given the same amount of available carbohydrates. Sensory evaluation revealed that OSF can be added to noodle to create sensorially acceptable products, though ratings for sensory characteristics decreased with increased fortification.

The purpose of this study is to prepare Maillard reaction products (MRPs) with both good emulsification and antioxidant activity, and the relationship between the Maillard reaction degree and structural changes of whey protein isolate (WPI) conjugated with xylose through wet-heating was explored. Browning intensity didn’t change while the free amino groups reduced significantly at the initial stage of Maillard reaction (MR). Amino acid analysis indicated that the lysine and arginine reduced significantly. The antioxidant property of the MRPs was significantly improved. The best emulsifying properties could be obtained in the middle degree of MR. The sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis illustrated that WPI and xylose formed high molecular weight conjugates. The circular dichroism spectra suggested that α-helix and random coil were increased while the β-sheet and β-turns were decreased after the MR. All of the MRPs exhibited a marked red shift in the maximum fluorescence intensity, indicating that the hydrophilicity of MRPs was enhanced.

Cardamine violifolia is a selenium (Se)-enriched plant in China. In this study, we prepared Se-enriched peptides (SPE) from C. violifolia by enzymatic hydrolysis. The peptides were then separated by ultrafiltration. The fraction with the highest in vitro antioxidant activity, SPE4, was obtained. Mice treated with SPE4 in D-galactose induced oxidative stress model showed significantly increased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and glutathione (GSH) content and reduced malondialdehyde (MDA) and protein carbonyl content in plasma and tissues. Furthermore, the in vivo anti-fatigue activities of SPE4 were evaluated by exhaustive swimming experiments. The weight-loaded swimming time of mice was prolonged by taking SPE4. The blood lactic acid (BLA) and urea nitrogen (BUN) content was decreased, and the level of hepatic glycogen (HG) was increased. Therefore, Se-enriched peptides form C. violifolia may be a beneficial ingredient to use in functional foods.

Necrosis is a form of cell death, which is related to various serious diseases such as cardiovascular disease, cancer, and neurodegeneration. Necrosis-avid agents (NAAs) selectively accumulated in the necrotic tissues can be used for imaging and/or therapy of related diseases. The aim of this study was to preliminarily investigate necrosis avidity of 131I-evans blue (131I-EB) and its mechanism. The biodistribution of 131I-EB at 24 h after intravenous administration showed that the radioactivity ratio of necrotic to viable tissue was 3.41 in the liver and 11.82 in the muscle as determined by γ counting in model rats. Autoradiography and histological staining displayed preferential uptake of 131I-EB in necrotic tissues. In vitro nuclear extracts from necrotic cells exhibited 82.3% of the uptake in nuclei at 15 min, as well as 79.2% of the uptake at 2 h after 131I-EB incubation. The DNA binding study demonstrated that evans blue (EB) has strong binding affinity with calf-thymus DNA (CT-DNA) (Ksv=5.08×105 L/(mol/L)). Furthermore, the accumulation of 131I-EB in necrotic muscle was efficiently blocked by an excess amount of unlabeled EB. In conclusion, 131I-EB can not only detect necrosis by binding the DNA released from necrotic cells, but also image necrotic tissues generated from the disease clinically. KEY WORDS: 131I-Evans blue, Necrosis avidity, Radioactivity, DNA binding, Necrosis imaging

Abstracts: The slow hydrogen sulphide (H2S) releasing compound S-allyl glutathione disulfide (GSSA) from garlic, which can release H2S via α carbon substitution, showed anti-aging effects on the chronological lifespan (CLS) of yeast Saccharomyces cerevisiae. Hormesis was observed, showing lifespan extension at nanomolar concentrations (100–200 nM), whereas at high concentration (1 mM) toxicity were observed. A possible explanation therefore might be the beneficial properties of the recently discovered gasotransmitter hydrogen sulfide (H2S). Yet, 2-vinyl-4H-1,3-dithiin (2-VDT) and 3-vinyl-4H-1,2-dithiin (3-VDT) from garlic appeared both inactive in terms of prolonging the lifespan of yeast. While for 2-VDT these findings seem reasonable since it cannot release H2S, for 3-VDT the contrary was expected as H2S releasing properties were observed. The underlying mechanism of H2S release of 3-VDT was proposed to be a similar α carbon substitution-like observed for GSSA.

Hydrogen sulphide (H2S) is a gasotransmitter with multiple cellular signaling functions, and substantial number of H2S donors has been reported for research and therapeutic applications. However, most of the H2S donors are synthetic compounds. Naturally occurring slow H2S releasing agents are rare, especially those found in fruits and vegetables. We report herein that 1,2,4-trithiolane (TTL), the major cyclic polysulphide from stinky bean, is a potent, slow releasing H2S donor. TTL is 6.35 times more effective than diallyl trisulphide (DATS) in terms of increasing the cellular H2S concentration in cultured cells. Moreover, TTL could release H2S in cultured cells for up to two days. HPLC and LC–MS study reveal that TTL releases H2S through a sluggish reaction with glutathione (GSH), during which the thiolate attacks the carbon to open the trithiolane ring, resulting in H2S and several glutathione-methylene-sulphide conjugates. The apparent rate constant was estimated to be (2.02 ± 0.38) × 10−5 s−1. Our results suggest that stinky bean, may be of potential as functional food with H2S donation property.

Blanched and unblanched garlic were fermented using L. plantarum for investigation of organosulphide profiles, hydrogen sulphide-releasing activity, pH, titratable activity and microbial growth. Both raw and blanched garlic preparations allowed growth of L. plantarum with corresponding lowering of pH below 4.0 and an increase in titratable acidity from an initial value of less 0.05% to 0.3 and 0.5%, respectively. Fermentation, alone, decreased allicin and vinyl dithiins, but increased the concentration of DATS. The H2S-releasing activity, expressed as DATS-E (mmol DATS/g oil), of raw-fermented (2.91) garlic was not significantly different to that of raw (4.74) garlic, but values in blanched (0.41) and blanched-fermented (0.71) samples significantly decreased. Reductions in DATS-E values in blanched and blanched-fermented garlic corresponded well with the negative effect of blanching on the organosulphide concentrations of the products. Fermentation with L. plantarum retains H2S-releasing activity by increasing DATS, despite notable losses in allicin and allicin transformation products.

This article contains experimental data on the identification and quantification of the organosulfides on boiled garlic extracts. Data included are related to the research article “Boiling enriches the linear polysulfides and the hydrogen sulfide-releasing activity of garlic” (R. Tocmo, Y. Wu, D. Liang, V. Fogliano, D. Huang, 2016) [1]. Characterization was carried out by GC–MS and HPLC. Dose-response curves obtained from the cell-based H2S-releasing capacity assay of allicin transformation products, namely vinyl dithiins and ajoene are also included. DATS-E values were calculated from these dose-response curves to quantify the contribution of the individual polysulfides to the H2S-releasing capacity of boiled extracts.

Type-II diabetes has become a health threat globally. One major challenge for diabetes patients is to control their post-prandial hyperglycaemia, which could be achieved through the inhibition of α-amylase and α-glucosidase. Lepisanthes alata (Malay cherry) was discovered as a promising edible plant with high starch hydrolase inhibition activities for corn starch hydrolysis with IC50 of its aqueous extracts at 0.77 ± 0.09 µg/mL (for porcine α-amylase) and 10.83 ± 0.67 µg/mL (for rat intestinal α-glucosidase). Proanthocyanidins were identified to be responsible as active compounds. The proanthocyanidin exhibited high degree (mDP at 27) of polymerization and was composed of (epi)catechins and (epi)gallocatechins linked through B-type 4–8 interflavanyl bonds. Inhibition kinetic study revealed that the proanthocyanidins were a mixed noncompetitive inhibitor against α-amylase but competitive inhibitor against α-glucosidase. Our discovery highlighted the potential of the leaves of L. alata for use in prevention of post prandial hyperglycaemia.

We found that Abelmoschus esculentus Moench (okra, or lady's finger) exhibits significant α-amylase and α-glucosidase inhibitory activity. Assay-guided fractionation of the okra extracts resulted in identification of oligomeric proanthocyanidins in unripe okra seeds as the compounds responsible to the activity. High-performance liquid chromatography (HPLC) analysis using a diol column revealed oligomers are a dominant composition with higher degree (>20) of polymerisation appearing as one large peak in the chromatogram. Thiolysis treatment of the proanthocyanidins using methyl thioglycolate produced thioether derivatives of (epi)gallocatechins and (epi)catechins as major products. Based on the ratio of terminal and extension units, the mean degree of polymerisation was estimated to be 21.97. B-type gallocatechin oligomers up to pentadecamer could be detected using matrix-assisted laser desorption/ionisation time of flight (MALDI-TOF) mass spectra.

Dietary organosulfur compounds commonly found in garlic and cruciferous vegetables are potent hypochlorite scavengers as measured using a novel fluorescence assay based on quantum dots (QDs) as the nanoprobe. By using hydrogen sulfide as a standard, we quantified the HClO scavenging capacity of organosulfides in the following order: cysteine > methionine > phenethylisothiocyanate > diallyldisulfide ~ dially trisulfide. The reaction products of these sulfides with hypochlorite were characterized by LC–MS spectra, which revealed that the sulfur atoms are the acceptor of oxygen from hypochlorite. Finally, the hypochlorite scavenging activity of garlic upon heat treatment reduced the ClO− scavenging activity significantly.

Hydrogen sulphide (H2S), viewed as a deadly environmental pollutant, is now intensively researched as the third gaseous signalling molecule, ubiquitously present and with a myriad of physiological functions. We studied garlic (Allium sativum L.) scapes, the underexplored yet widely consumed “flower stalks” of garlic, for their organosulphide constituents and H2S-releasing activity. Oils obtained from pH-adjusted (pH 3.0–9.0) puree contained 15 organosulphides that showed sensitivity to the pH values of the processing media. Disulphides are significantly higher in the oil obtained at basic pH while trisulphides and cyclic organosulphides were much higher in the oils isolated at the acidic to weakly acidic pH values. A cell-based fluorescent method was used to quantify the H2S-releasing capacity, expressed as diallyl trisulphide equivalents (DATS-E in mmol DATS/g). DATS-E values significantly increased with increasing concentrations of trisulphides and tetrasulphides but showed inverse relationship with the increase in disulphides concentration. Common cooking method of stir-frying resulted in loss of more than 96% of the organosulphides and the oil obtained had an 85-fold lower DATS-E value.

Hydrogen sulphide (H2S) is a gaseous signalling molecule with multiple biological functions in the human body. Previous research demonstrates that diallyl trisulphide (DATS) and diallyl disulphide (the two major compounds of garlic oil) can be metabolized to generate H2S in biological conditions and modulate cell signalling. In this paper, a fluorescent method for quantification of H2S releasing capacity in cell lines was developed. MCF-7 cells in 96 well plate were incubated with a H2S probe BCu for 3 h, then treated with H2S donors for 2 h, which would be metabolized by the cells and produce H2S. The resulting H2S was captured by the probe and turn on its fluorescence, which was measured with a microplate reader. Linear dose response could be established between organosulphur concentration and fluorescence intensity, and the H2S releasing capacity of a sample was determined by comparing the slope of the regression curve with that of a DATS standard obtained in parallel. With this method, the H2S releasing capacity of ten organosulphur rich fruits and vegetables (garlic, red onion, yellow onion, scallion, shallot, leek, spring onion, Chinese chives, durian, and stinky beans) were evaluated and ranked. Stinky beans (a vegetable from Southeast Asia) topped the ranking with very high H2S releasing capacity, followed by garlic and yellow onion. Our work provides new thinking on the health benefits of organosulphur-rich foods.