In vitro biomechanical study of rotational stabilizers of the canine elbow joint

OBJECTIVE: To develop a model for measuring rotary stability of the canine elbow joint and to evaluate the relative contribution of the anconeal process (AN), lateral collateral ligament (LCL), and medial collateral ligament (MCL). SAMPLE POPULATION: 18 forelimbs from 12 canine cadavers. PROCEDURE: Forelimbs were allocated to 3 experimental groups (6 forelimbs/group). Each intact forelimb was placed in extension at an angle of 135 degrees and cycled 50 times from -16 degrees (pronation) to +28 degrees (supination) in a continuous manner at 2.0 Hz. Cycling was repeated following sectioning of the structure of interest (group 1, AN; group 2, LCL; and group 3, MCL). Torque at -12 degrees (pronation) and +18 degrees (supination) was measured for each intact and experimentally sectioned limb. A Student t test was performed to compare torque values obtained from intact verses experimentally sectioned limbs and for comparison with established criteria for differentiation of primary (> or = 33%), secondary (10 to 33%), and tertiary rotational stabilizers (< 10%). RESULTS: In pronation, the AN was the only primary stabilizer (65%). For supination, the LCL was a primary stabilizer (48%), AN was a secondary stabilizer (24%), and MCL was a tertiary stabilizer (7%). CONCLUSIONS AND CLINICAL RELEVANCE: With the elbow joint in extension at an angle of 135 degrees, the AN is a primary rotational stabilizer in pronation, and the LCL is a primary stabilizer in supination. Disruption of the AN or LCL may affect rotary range of motion or compromise stability of the elbow joint in dogs.     

Stability of copigmented anthocyanins and ascorbic acid in a grape juice model system

The stability of red grape anthocyanins (Vitis vinifera) was evaluated in a model juice system during normal (25 degrees C) and accelerated storage (35 degrees C) in the presence of ascorbic acid. Rosemary polyphenolic cofactors (0, 0.2, and 0.4% v/v) were evaluated as anthocyanin stabilizing agents. Cofactor addition resulted in concentration-dependent hyperchromic (up to 178%) and bathochromic (up to 23 nm) shifts, indicating a more intense red coloration of the models. Anthocyanin and ascorbic acid degradation followed first-order kinetics during storage. Results showed that copigmented treatments underwent a lower conversion of L-ascorbic acid into dehydroascorbic acid during storage when compared to the control, favorably impacting the vitamin retention of these models. Copigmentation did not affect anthocyanin degradation in the absence of ascorbic acid but in its presence aided to retain a higher anthocyanin content than the control. This study indicated that the addition of anthocyanin cofactors could be used to reduce the pigment and vitamin degradation while masking detrimental color changes in anthocyanin containing products.     

The impact of packaging materials on the antioxidant phytochemical stability of aqueous infusions of green tea (Camellia sinensis) and yaupon holly (Ilex vomitoria) during cold storage

Ready to drink (RTD) teas are a growing segment in the beverage category, brought about by improvements in the flavor of these products and healthy market trends driven by consumers. The presented results evaluated the antioxidant phytochemical stability of RTD teas from aqueous infusions of traditional green tea (Camellia sinensis) and a botanical tea from yaupon holly (Ilex vomitoria) as influenced by packaging materials during cold storage. Two common packaging materials for RTD products are glass and polyethylene terephthalate (PET) and have been compared to a retortable pouch (RP), an emerging packaging material for various types of food since it is durable, inexpensive, lightweight, and easy to sterilize. Storage stability was then evaluated for each aqueous infusion prepared at 10 g/L at 90 °C for 10 min and evaluated at 3 °C in the absence of light over 12 weeks. Analyses included quantification and characterization of individual polyphenolics by high-performance liquid chromatography-photodiode array and liquid chromatography-electrospray ionization-mass spectrometry as well as changes in total antioxidant capacity. For green tea, concentrations of the three major flavan-3-ols, epigallocatechin gallate, epigallocatechin, and epicatechin gallate were better retained in glass bottles as compared to other packages over 12 weeks. In yaupon holly, chlorogenic acid and its isomers that were the predominant compounds were generally stable in each packaging material, and a 20.6-fold higher amount of saponin was found as compared to green tea, which caused higher stability of flavonol glycosides present in yaupon holly during storage. The antioxidant capacity of green tea was better retained in glass and PET versus RP, whereas no differences were again observed for yaupon holly. Results highlight the superiority of oxygen-impervious glass packaging, but viable alternatives may be utilizable for RTD teas with variable phytochemical compositions.     

Polyphenolics and Antioxidant Capacity of White and Blue Corns Processed into Tortillas and Chips

White and blue corns of Mexican and American origins were lime-cooked to obtain nixtamals with optimal moisture (48–50%) for tortillas and chips. Blue kernels had less bulk density, softer endosperm and, consequently, required less cooking time than the white kernels. The optimum cooking regime for the white kernels was 100°C for 20 min, while the optimum for both pigmented genotypes was 90°C for 0 min (until the lime-cooking solution reached 90°C). Doughs, tortillas, and chips were characterized by total soluble phenolics (TSP), anthocyanins (ACN), and antioxidant capacity (AOX). A dough acidification procedure using fumaric acid (pH 5.2) was assessed as a means to improve TSP, ACN, and AOX retention. The Mexican blue corn had higher AOX (16%) than the American blue genotype, although the latter had a threefold higher TSP content (12.1 g/kg, dwb). Mexican and American blue corns had higher AOX capacity (29.6 and 25.6 μM trolox equivalents [TE]/g dwb), respectively, than the white corn (17.4 μM TE/g). White corns did not have detectable amounts of ACN, while blue Mexican and American kernels contained 342 and 261 mg/kg. Lime cooking had the greatest negative impact on the stability of TSP, ACN, and AOX. However, the acidification reduced ACN, TSP, and AOX losses by 8–23, 3–14, and 4–15%, respectively. Similar ACN losses were observed for both types of blue kernels when processed into nixtamal/dough (47%); however, ACN losses in tortillas and chips manufactured from the American blue genotype were higher (63 and 81%, respectively) than those of Mexican blue corn products (54 and 75%). ACN losses were highly correlated to TSP (r = 0.91) and AOX capacity losses (r = 0.94).     

Black soil blindness: A new mycotoxicosis of cattle grazing Corallocytostroma-infected Mitchell grass (Astrebla spp)

A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named ‘black soil blindness’ because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease is present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.     

Enhancing the retention of phytochemicals and organoleptic attributes in muscadine grape juice through a combined approach between dense phase CO2 processing and copigmentation

This study evaluated the phytochemical stability and organoleptic attributes of an ascorbic acid-fortified muscadine grape juice as affected by dense phase CO2 processing (DP-CO2) and addition of thyme polyphenolic cofactors (Thymus vulgaris; 1:100 anthocyanin-to-cofactor molar ratio) in efforts to prevent phytochemical losses that occur during storage of anthocyanin-containing beverages, especially in the presence of carbonyl compounds commonly produced during thermal processing and storage. DP-CO2 processing insignificantly altered initial juice phytochemical and antioxidant content, whereas thermal pasteurization reduced anthocyanins (263 mg/L), ascorbic acid (42 mg/L), soluble phenolics (266 mg/L), and antioxidant capacity (6 microM Trolox equivalents/mL). Similar trends were observed during storage, and data showed that increasing the CO2 level from 8 to 16% during DP-CO2 was instrumental in reducing juice phytochemical and antioxidant degradation. Copigmentation was instrumental in retaining higher anthocyanin, soluble phenolics, and antioxidant capacity during storage without affecting initial juice aroma and flavor characteristics. Moreover, on the basis of overall likeability scores, panelists preferred copigmented juices, which had increased juice color intensity and masked the detrimental color fading that occurred during storage, especially when compared to thermally pasteurized juices. DP-CO2 and copigmentation were effective strategies to reduce phytochemical and color deterioration that occurred in muscadine juice during storage without affecting their organoleptic attributes.     

Flavonol-rich fractions of yaupon holly leaves (Ilex vomitoria, Aquifoliaceae) induce microRNA-146a and have anti-inflammatory and chemopreventive effects in intestinal myofibroblast CCD-18Co cells

Polyphenolics extracted from yaupon holly (Ilex vomitoria, Aquifoliaceae) (YH) leaves were investigated in human colon cells for their chemopreventive and anti-inflammatory activities. An activity-guided fractionation allowed the selection of YH flavonol-rich fraction due to its preferential inhibition of HT-29 colon cancer viability over the normal CCD-18Co colon cells. Quercetin and kaempferol 3-rutinosides, main components identified in this fraction, protected CCD-18Co cells against reactive oxidative species (ROS) in part due to increased activity of antioxidant enzymes. In addition, up-regulation of microRNA-146a (miR-146a) known as a negative regulator of pro-inflammatory NF-κB activation was the underlying molecular mechanism that protected CCD-18Co from inflammation.     

Fruit maturity and juice extraction influences ellagic acid derivatives and other antioxidant polyphenolics in muscadine grapes

Polyphenolic compounds including ellagic acid, ellagic acid derivatives, and anthocyanins were characterized and quantified by novel chromatographic conditions in eight muscadine grape (Vitis rotundifolia) cultivars and evaluated for antioxidant capacity as influenced by two ripening stages and their location within the fruit (skin, pulp, and juice). All polyphenolics generally increased as fruit ripened and the highest concentrations were located in the skins. Free ellagic acid, ellagic acid glycosides, and total ellagic acid ranged from 8 to 162, 7 to 115, and 587 to 1900 mg/kg, respectively, in the skin of ripe grapes. Hot-pressed juices contained considerably lower polyphenolic concentrations than were present in whole grapes. Five anthocyanidins were present in each cultivar in variable concentrations (delphinidin > petunidin > malvidin + peonidin > cyanidin). Antioxidant capacity was appreciably influenced by cultivar, maturity, and location in the fruit with good correlations to soluble phenolics found in both methanolic and ethyl acetate extracts (r = 0.83 and 0.92, respectively).