Tory L. Parker

Synergistic and Antagonistic Interactions of Phenolic Compounds Found in Navel Oranges

Phenolic compounds are known to have antioxidant and antimicrobial properties. These properties may be useful in the preservation of foods or beverages. The interactive antioxidant capacity of phenolic compounds within foods has not been well explored. Interactions of individual phenolic compounds (chlorogenic acid, hesperidin, luteolin, myricetin, naringenin, p-coumaric acid, and quercetin) at the concentrations found in navel oranges (Citrus sinensis) were analyzed for their antioxidant capacity to observe potential antagonistic, additive, or synergistic interactions. Mixtures of 2, 3, and 4 phenolic compounds were prepared. The Oxygen Radical Absorbance Capacity (ORAC) assay was used to quantify the antioxidant capacities of these combinations. Three different combinations of 2 compounds and 5 combinations of 3 compounds were found to be synergistic. One antagonistic combination of 2 was also found. No additional synergism occurred with the addition of a 4th compound. A model was developed to explain our results. Reduction potentials, relative concentration, and the presence or absence of catechol (o-dihydroxy benzene) groups were factors in the model. Practical Application: Understanding how combinations of fruit antioxidants work together will support their future use in preservation of foods and/or beverages.

Evaluation of synergistic antioxidant potential of complex mixtures using oxygen radical absorbance capacity (ORAC) and electron paramagnetic resonance (EPR)

Previous research has demonstrated that certain combinations of compounds result in a decrease in toxic or pro-oxidative effects, previously noted when compounds were administered singly. Thus, there is a need to study many complex interactions further. Two in vitro techniques [electron paramagnetic resonance (EPR) and oxygen radical absorbance capacity (ORAC) assays] were used in this study to assess pro- and antioxidant capacity and synergistic potential of various compounds. Rutin, p-coumaric acid, abscisic acid, ascorbic acid, and a sugar solution were evaluated individually at various concentrations and in all 26 possible combinations at concentrations found in certain foods (honey or papaya), both before and after simulated digestion. EPR results indicated sugar-containing combinations provided significantly higher antioxidant capacity; those combinations containing sugars and ascorbic acid demonstrated synergistic potential. The ORAC assay suggested additive effects, with some combinations having synergistic potential, although fewer combinations were significantly synergistic after digestion. Finally, ascorbic acid, caffeic acid, quercetin, and urate were evaluated at serum-achievable levels. EPR analysis did not demonstrate additive or synergistic potential, although ORAC analysis did, principally in combinations containing ascorbic acid.

Antioxidant capacity interactions and a chemical/structural model of phenolic compounds found in strawberries

The interactive antioxidant capacity of phenolic compounds from specific foods has not been well explored. The antioxidant capacity of a whole fruit exceeds the sum of the antioxidant capacities of individual antioxidants within that fruit, suggesting synergism among compounds. The interactions of seven phenolic compounds (p-coumaric acid, cyanidin, catechin, quercetin-3-glucoside, kaempferol, pelargonidin and ellagic acid) at relative concentrations found in strawberries were tested using the oxygen radical absorbance capacity assay. Statistically significant synergism was found for three combinations of two phenolic compounds, and among five combinations of three phenolic compounds. Statistically significant antagonism was observed among two combinations of two phenolic compounds and among one combination of three compounds. A chemical/structural model that best explained the results included reduction potentials, relative concentration, and the presence or absence of catechol (o-dihydroxy benzene) groups. This work demonstrates unique interactions that occur in a complex environment within the framework of strawberries. The synergism discovered at food-based antioxidant ratios could be applied to food preservation.

Controlling for sugar and ascorbic acid, a mixture of flavonoids matching navel oranges significantly increases human postprandial serum antioxidant capacity

Fruit and vegetable consumption reduces the risk for cardiovascular disease development. The postprandial state is an important contributor to chronic disease development. Orange flavonoids may reduce postprandial oxidation. It was hypothesized that a mixture of orange flavonoids would reduce postprandial oxidation better than a single orange flavonoid or orange sugar and ascorbic acid, but not as well as orange juice, when consumed with a typical breakfast. A placebo-controlled crossover trial (16 male and female participants, 4 treatments, 4 visits) was carried out. Treatments were placebo (ascorbic acid and sugar equivalent to orange juice); placebo plus hesperidin; placebo plus hesperidin, luteolin, and naringenin (mixture; found to have synergistic antioxidant properties in vitro in previous work); and orange juice (positive control). Serum oxygen radical absorbance capacity (ORAC), total plasma phenolics (TP), and serum lipoprotein oxidation (LO) were measured after a 12-hour baseline fast and at 1, 2, and 3 hours after sample consumption. The placebo plus mixture and orange juice groups were significantly increased in ORAC and LO lag time. Data for TP were inconsistent with ORAC and LO. Contrary to previous studies attributing the protective postprandial effect to fructose and ascorbate in other fruit trials, orange phenolic compounds contribute directly to the postprandial oxidative protection of serum, despite an inconsistent change in serum TP.

Consumption of blueberries with a high-carbohydrate, low-fat breakfast decreases postprandial serum markers of oxidation.

We sought to determine whether consumption of blueberries could reduce postprandial oxidation when consumed with a typical high-carbohydrate, low-fat breakfast. Participants (n 14) received each of the three treatments over 3 weeks in a cross-over design. Treatments consisted of a high blueberry dose (75 g), a low blueberry dose (35 g) and a control (ascorbic acid and sugar content matching that of the high blueberry dose). Serum oxygen radical absorbance capacity (ORAC), serum lipoprotein oxidation (LO) and serum ascorbate, urate and glucose were measured at fasting, and at 1, 2 and 3 h after sample consumption. The mean serum ORAC was significantly higher in the 75 g group than in the control group during the first 2 h postprandially, while serum LO lag time showed a significant trend over the 3 h for both blueberry doses. Changes in serum ascorbate, urate and glucose were not significantly different among the groups. To our knowledge, this is the first report that has demonstrated that increased serum antioxidant capacity is not attributable to the fructose or ascorbate content of blueberries. In summary, a practically consumable quantity of blueberries (75 g) can provide statistically significant oxidative protection in vivo after a high-carbohydrate, low-fat breakfast. Though not tested directly, it is likely that the effects are due to phenolic compounds, either directly or indirectly, as they are a major family of compounds in blueberries with potential bioactive activity.

The Effect of Seat Location and Movement or Permanence on Student-Initiated Participation

There is conflicting evidence on the effect of seat location on student performance and participation in the classroom. The two major hypotheses are (1) that seat location influences student behavior and (2) that seat preference and selection is associated with personality traits of students. This study evaluated both hypotheses within a 55 student senior nutritional biochemistry class. Alternating every other seat, half of the class was randomly assigned a permanent seat while the other half was randomly reassigned a different seat each class period. Students sitting in the front of the classroom in the stay group made significantly more comments per student per day than stay group students in the back, in agreement with other studies. The move group, however, showed increased overall participation with no significant difference between the front and back of the classroom. Findings suggest a more flexible explanation—that students may adopt or reject an implied social role in which seat location and personality traits are influential factors.

Antiinflammatory Activity of Cinnamon (Cinnamomum zeylanicum) Bark Essential Oil in a Human Skin Disease Model

The effect of cinnamon (Cinnamomum zeylanicum) bark essential oil (CBEO) on human skin cells has not been elucidated. Therefore, we investigated the activity of a commercially available CBEO in a validated human dermal fibroblast system, a model of chronic inflammation and fibrosis. We first evaluated the impact of CBEO on 17 protein biomarkers that play critical roles in inflammation and tissue remodeling. The impact of CBEO on genome‐wide gene expression was also evaluated. CBEO showed strong anti‐proliferative effects on skin cells and significantly inhibited the production of several inflammatory biomarkers, including vascular cell adhesion molecule‐1, intercellular cell adhesion molecule‐1, monocyte chemoattractant protein‐1, interferon gamma‐induced protein 10, interferon‐inducible T‐cell alpha chemoattractant, and monokine induced by gamma interferon. In addition, CBEO significantly inhibited the production of several tissue remodeling molecules, including epidermal growth factor receptor, matrix metalloproteinase‐1, and plasminogen activator inhibitor‐1. Macrophage colony‐stimulating factor, which is an immunomodulatory protein molecule, was also significantly inhibited by CBEO. Furthermore, CBEO significantly modulated global gene expression and altered signaling pathways, many of which are important in inflammation, tissue remodeling, and cancer biology. The study shows that CBEO is a promising antiinflammatory agent; however, further research is required to clarify its clinical efficacy.

Biological activity of vetiver (Vetiveria zizanioides) essential oil in human dermal fibroblasts

Abstract Vetiver (Vetiveria zizanioides) essential oil (VEO) has a long history of use. However, research on its biological activity in human skin cells is scarce. In this study, we investigated the biological activity of VEO in a pre-inflamed human dermal fibroblast model, which was designed to mimic the disease biology of chronic inflammation and fibrosis. We analyzed the impact of VEO on the levels of 17 important protein biomarkers pertinent to immune response and tissue remodeling. VEO exhibited strong antiproliferative activity in these cells and significantly inhibited the production of collagen III, an important molecule for skin and tissue remodeling processes. We also studied the effect of VEO on regulating genome-wide gene expression. VEO robustly impacted many genes and signaling pathways that are closely related to tissue remodeling and metabolism, among others. Specifically, VEO significantly impacted pathways for cholesterol synthesis and metabolism. This study provides the first evidence of the biological activity of VEO in human dermal fibroblasts. Though a definite conclusion remains elusive, the data suggest that VEO has therapeutic potential for both cosmetic and metabolic health care products. Further research into VEO’s biological and pharmacological mechanisms of action is recommended.

Essential oils diversely modulate genome-wide gene expression in human dermal fibroblasts

Abstract The increasing popularity of essential oils for skincare has led to investigation of their biological effects in human skin cells. In this study, we investigated the biological activities of three commercially available essential oils, i.e. rosemary oil, wild orange oil, and a blend (commercial name: Deep Blue) composed of oils from wintergreen, camphor, peppermint, blue tansy, German chamomile, Helichrysum, and Osmanthus, in a pre-inflamed human dermal fibroblast culture model, simulating chronic inflammation. The impact of essential oils on proteins associated with inflammation and tissue remodeling and on the genome-wide expression of 21,224 genes was investigated. The three essential oils diversely modulated global gene expression. Ingenuity Pathway Analysis showed that the oils affected numerous critical genes and signaling pathways. Specifically, rosemary oil influenced processes involved in cancer signaling and metabolism; orange oil affected processes related to cancer signaling, immunomodulation, and metabolism; the blend influenced inflammation, immunomodulation, and wound healing. These findings are largely consistent with the existing literature, supporting the beneficial biological activities of these essential oils. Our study provides the first evidence indicating how these essential oils affect genome-wide gene expression in human skin cells and establishes a basis for further research into their biological mechanisms of action.

Evaluation of the Health Benefits of a Multivitamin, Multimineral, Herbal, Essential Oil–Infused Supplement: A Pilot Trial

ABSTRACT This study was designed to quantitatively evaluate the health benefits of a multivitamin, multimineral, herbal, essential oil–infused supplement using serum biomarkers. We also qualitatively evaluated the health effects of this supplement using a survey. Sixteen participants were recruited to take the supplement as directed for two months. The levels of the following serum components were measured in the participants: total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, lipoprotein(a), LDL/HDL cholesterol ratio, total/HDL cholesterol ratio, ferritin, fibrinogen, C-reactive protein, insulin, testosterone, sex hormone binding globulin, free androgen index, red blood cell magnesium, homocysteine, coenzyme Q10, lipid peroxides, alpha-tocopherol, gamma-tocopherol, cardiovascular index, eicosapentaenoic acid (EPA), arachidonic acid (AA), and the AA/EPA ratio. The following markers were significantly improved (p <.05) after two months of supplementation: HDL cholesterol, LDL/HDL cholesterol ratio, fasting insulin, homocysteine, serum vitamin E, EPA, and the AA/EPA ratio. These findings demonstrate that the supplementation had significant positive effects on biochemical indicators of cardiovascular health, antioxidant status, inflammation, and blood glucose regulation. All of the outcomes in the 16-item qualitative survey were improved after two months of supplementation. Twelve of these outcomes were significantly improved. The participants reported more mental clarity, energy, motivation, control, balance, and happiness, while reporting less back pain, muscle pain, cold and flu incidence, anxiety, frustration, and irritation at the end of the two-month supplementation period. Although definite clinical efficacy remains elusive, these results suggest that the supplement may provide a broad range of health benefits for users in a short period.