Comparative analysis of phytochemicals and polar metabolites from colored sweet potato (Ipomoea batatas L.) tubers

Food Science and Biotechnology - We determined the phytochemical diversity, including carotenoids, flavonoids, anthocyanins, and phenolic acids, in sweet potatoes (Ipomoea batatas L.) with...     

Inhibitory effects of natural plants of Jeju Island on elastase and MMP-1 expression

In order to search for new active cosmetic ingredients of natural origin, we screened about 60 plants collected from Jeju Island, which is located in the southernmost part of the Republic of Korea. We investigated their free radical scavenging activity, elastase inhibition activity, and reduction of MMP-1 mRNA expression for the development of anti-aging ingredients as raw materials for use in cosmetics. In the free radical scavenging capacity assay, 12 extracts, including Typha orientalis (seed) and Torreya nucifera (leaf), showed significant free radical scavenging activity (up to SC50 < 30 μg/ml). Among these extracts, Nymphaea tetragona (rhizome) extract showed the highest free radical scavenging activity (SC50 = 4.7 μg/ml). In the anti-elastase inhibition assay, seven extracts, including T. orientalis (seed) and Persicaria hydropiper (whole plant), showed high inhibitory activity (>50% at 100 μg/ml). Among these extracts, P. hydropiper (whole plant) extract showed the highest elastase inhibition activity (IC50 = 46.7 μg/ml). In the MMP-1 expression assay using RT-PCR, T. orientalis (seed), Pyrrosia hastata (root), and Capsicum annum (whole plant) showed slightly lower inhibition activity than EGCG, which was used as a control. Furthermore, four extracts, including P. hydropiper (whole plant), Filipendula glaberrima (root), N. tetragona (root), and Camellia japonica (leaf), completely inhibited the expression of MMP-1 in human fibroblast cells. The results showed that four of the 60 plant extracts may hold potential for use as natural active ingredients for anti-aging cosmetics.     

Effects of rendering and α-tocopherol addition on the oxidative stability of horse fat

Food Science and Biotechnology - Oxidative stability of horse fat rendered at 70&nbsp;°C, − 0.1&nbsp;MPa under vacuum and 110&nbsp;°C, 0.1&nbsp;MPa from horse...     

Slowly digestible sweetpotato flour: Preparation by heat-moisture treatment and characterization of physicochemical properties

The preparation and physicochemical characteristics of sweetpotato flour with increased slowly digestible starch (SDS) fraction were investigated under various heat-moisture treatment (HMT) conditions. The optimum conditions for preparing slowly digestible sweetpotato flour established using response surface methodology were moisture content of 22%, temperature of 103°C, and treatment time of 5.8 h. The highest SDS content in heat-moisture treated sweetpotato flour was 57.6%. The relative crystallinity of heat-moisture treated sweetpotato flour decreased, but the X-ray diffraction pattern maintained the A-type. The DSC of the heatmoisture treated flour showed a decreased gelatinization temperature range and gelatinization enthalpy compared with native one. The viscosity profiles and values changed significantly with HMT, resulting in a higher pasting temperature, decrease of the viscosity values, and no breakdown. It indicates that heat-moisture treated sweetpotato flour is more stable at high temperatures and shear rates than native one.     

Cyanidin-3-O-(2″-xylosyl)-glucoside, an anthocyanin from Siberian ginseng (Acanthopanax senticosus) fruits, inhibits UVB-induced COX-2 expression and AP-1 transactivation

Cyanidin-3-O-(2″-xylosyl)-glucoside (C-3-O-(2″-xylosyl)-G) was analyzed as an active constituent from the fruit of Siberian ginseng (Acanthopanax senticosus) using a HPLC diode array detection-electrospray ionization/mass spectrometry analysis system and the effect of C-3-O-(2″-xylosyl)-G on UVB-induced inflammatory signaling in JB6 P+ cells was investigated. C-3-O-(2″-xylosyl)-G inhibited UVB-induced cyclooxygenase (COX)-2 expression and promoter binding activity in JB6 P+ cells and JB6 P+ cells stably transfected with the COX-2 luciferase reporter plasmid. It inhibited both the UVB-induced activator protein-1 (AP-1) and nuclear factor (NF)-κB transactivation in JB6 P+ cells stably transfected with the AP-1 and NF-κB luciferase reporter plasmids. Additionally, C-3-O-(2″-xylosyl)-G significantly suppressed UVB-induced upregulated phosphorylation of c-Jun N terminal kinase, MEK/extracellular signaling kinase, and mitogen activated protein kinase kinase (MAPKK) 3/6 in JB6 P+ cells. These results indicate that C-3-O-(2″-xylosyl)-G may be a promising chemopreventive material that acts by suppressing COX-2 expression and AP-1 and NF-κB transactivation and JNK, MAPKK3/6, and MEK/ERK1/2 phosphorylation.     

Effects of lipophilic and hydrophilic antioxidants in oil-in-water emulsions under chlorophyll photosensitization

Antioxidative or prooxidative properties of α-tocopherol, Trolox, ascorbic acid, and ascorbyl-palmitate at the concentration of 0.1 and 1.0 mM were determined in oil-in-water (O/W) emulsions under chlorophyll photosensitization. Headspace oxygen depletion, lipid hydroperoxides, and headspace volatile analyses were conducted to determine the oxidative stability of O/W emulsions. For 32 h visible light irradiation, depleted headspace oxygen content in O/W emulsions were in the order of samples containing Trolox, ascorbic acid, ascorbyl palmitate, α-tocopherol, without antioxidants under light, and samples in the dark, which implies that all the added compounds acted prooxidant. These prooxidative properties of added compounds can be observed in the results of lipid hydroperoxides and headspace volatiles. Samples containing ascorbic acid and ascorbyl palmitate retained higher chlorophyll content than those containing Trolox up to 16 h. Increases of concentration of Trolox, ascorbic acid, and ascorbyl palmitate from 0.1 to 1.0 mM increased the lipid oxidation products whereas α-tocopherol decreased the degree of lipid oxidation implying α-tocopherol may not share the same prooxidant mechanisms compared to other compounds in chlorophyll sensitized O/W emulsions.     

SB365, Pulsatilla saponin D suppresses the proliferation of human colon cancer cells and induces apoptosis by modulating the AKT/mTOR signalling pathway

Pulsatilla koreana has been used as a traditional medicine for the treatment of several diseases. The purpose of this study was to determine if SB365, Pulsatilla saponin D isolated from the root of P. koreana inhibits the progression of colon cancer. We found that SB365 strongly suppressed the growth and proliferation of colon cancer cells and induced their apoptosis. Also, SB365 showed anti-angiogenic activity by decreasing the expression of HIF-1α and VEGF. These results were confirmed by an in vivo study showing that SB365 significantly inhibited tumor growth by the induction of apoptosis and inhibition of angiogenesis with stronger anticancer activity than 5-FU. When further examined for its anticancer mechanism, SB365 effectively suppressed the AKT/mTOR pathway both in vitro and in vivo. Taken together, our study demonstrated that SB365 inhibits the AKT/mTOR pathway, leading to the suppression of tumor growth and angiogenesis together with induction of apoptosis. Therefore, SB365 is a good candidate as a natural product for use in the treatment of colon cancer.     

Effect of phosvitin on lipid and protein oxidation in ground beef treated with high hydrostatic pressure

In this study, we aimed to examine the effect of phosvitin on lipid and protein oxidation of raw and cooked ground beef treated with high hydrostatic pressure (HHP). Ground beef patty with 0, 500, or 1000 mg phosvitin/kg meat was treated with HHP at 0.1, 300, or 600 MPa. Half of the patties were used in a raw meat analysis, and the other half were used in a cooked meat analysis. Phosvitin and HHP treatment at 300 MPa synergistically reduced microbial growth, and HHP treatment at 600 MPa reduced microbial counts to undetectable levels (< 1 log CFU/g) throughout the length of the study in all samples. Phosvitin delayed lipid and protein oxidation in HHP-treated cooked and raw ground beef, respectively. However, phosvitin had no effect on the color changes of raw ground beef attributable to HHP. The results indicated that phosvitin could enhance the stability of lipids and proteins but not color changes of raw ground beef caused by HHP.     

Effects of pectinolytic yeast on the microbial composition and spoilage of olive fermentations

This study resulted in the identification of pectinolytic yeasts in directly brined Sicilian-style green olive fermentations and examination of the influence of those yeasts on the microbial composition and quality of fermented olives. Firstly, defective olives processed in Northern California from 2007 to 2008 and characterized by high levels of mesocarp tissue degradation were found to contain distinct yeast and bacterial populations according to DNA sequence-based analyses. Strains of (pectinolytic) Saccharomyces cerevisiae, Pichia manshurica, Pichia kudriavzevii, and Candida boidinii isolated from directly brined olives were then inoculated into laboratory-scale olive fermentations to quantify the effects of individual yeast strains on the olives. The pH, titratable acidity, and numbers of lactic acid bacteria (LAB) and yeasts varied between the fermentations and fermentations inoculated with P. kudriavzevii and C. boidinii promoted the development of LAB populations. Olive tissue structural integrity declined significantly within 30, 74, and 192 days after the inoculation of pectinolytic S. cerevisiae, P. manshurica and C. boidinii, respectively. In comparison, tissue integrity of olives in control fermentations remained intact although pectinolytic yeasts were present. Notably, pectinolytic yeasts were not found in fermentations inoculated with (non-pectinolytic) P. kudriavzevii and olives exposed to a 1:1 ratio of P. kudriavzevii and P. manshurica exhibited no significant tissue defects. This study showed that pectinolytic yeast are important components of directly brined green olive fermentations and damage caused by pectinolytic yeasts might be prevented by other microbial colonists of the olives.     

Comparison of constituents, antioxidant potency, and acetylcholinesterase inhibition in Lentinus edodes, Sparassis crispa, and Mycoleptodonoides aitchisonii

This study evaluates three edible mushrooms: Lentinus edodes, Sparassis crispa, and Mycoleptodonoides aitchisonii, in terms of acetylcholinesterase (AChE) inhibition, antioxidant potency and constituents free amino acids and mineral. The concentration of essential amino acids was found to be 34.10 mg/g in M. aitchisonii, 26.25 mg/g in S. crispa, 25.99 mg/g in L. edodes. S. crispa displayed the highest DPPH scavenging activity and phenolic contents. The best results for AChE inhibition were obtained from M. aitchisonii. These results suggest that M. aitchisonii has high potential for cognitive improvement by AChE inhibition and antioxidant potency.