Agriculture and Agri-Food Canada

About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.

Avenanthramides and Phenolic Acids from Oats Are Bioavailable and Act Synergistically with Vitamin C to Enhance Hamster and Human LDL Resistance to Oxidation

Abstract: The intake of phenolic acids and related polyphenolic compounds has been inversely associated with the risk of heart disease, but limited information is available about their bioavailability or mechanisms of action. Polyphenolics, principally avenanthramides, and simple phenolic acids in oat bran phenol-rich powder were dissolved in HCl:H2O:methanol (1:19:80) and characterized by HPLC with electrochemical detection. The bioavail- ability of these oat phenolics was examined in BioF1B hamsters. Hamsters were gavaged with saline containing 0.25 g oat bran phenol-rich powder (40 mol phenolics), and blood was collected between 20 and 120 min. Peak plasma concentrations of avenanthramides A and B, p-coumaric, p-hydroxybenzoic, vanillic, ferulic, sinapic, and syringic acids appeared at 40 min. Although absorbed oat phenolics did not enhance ex vivo resistance of LDL to Cu 2 -induced oxidation, in vitro addition of ascorbic acid synergistically extended the lag time of the 60-min sample from 137 to 216 min (P 0.05), unmasking the bioactivity of the oat phenolics from the oral dose. The antioxidant capability of oat phenolics to protect human LDL against oxidation induced by 10 mol/L Cu 2 was also determined in vitro. Oat phenolics from 0.52 to 1.95 mol/L increased the lag time to LDL oxidation in a dose-dependent manner (P 0.0001). Combining the oat phenolics with 5 mol/L ascorbic acid extended the lag time in a synergistic fashion (P 0.005). Thus, oat phenolics, including avenanthramides, are bioavailable in hamsters and interact synergistically with vitamin C to protect LDL during oxidation. J. Nutr. 134: 1459 -1466, 2004.

Cover crops to increase soil microbial diversity and mitigate decline in perennial agriculture. A review

Abstract: Commercial perennial agriculture is prone to declining productivity due to negative plant-soil feedback. An alternative to costly and environmentally harmful conventional treatment such as soil fumigation could be to manipulate soil microbial diversity through careful selection and management of cover crop mixtures. Although cover crops are already used in these systems for other reasons, their capacity to influence soil biota is unexploited. Here, we examine the role of plant diversity and identity on plant-soil feedbacks in the context of perennial agriculture. We identify key microorganisms involved in these feedbacks and explore plant-based strategies for mitigating decline of perennial crop plants. We conclude that (1) increasing plant diversity increases soil microbial diversity, minimizing the proliferation of soil-borne pathogens; (2) populations of beneficial microbes can be increased by increasing plant functional group richness, e.g., legumes, C4 grasses, C3 grasses, and non-leguminous forbs; (3) brassicas suppress fungal pathogens and promote disease-suppressive bacteria; (4) native plants may further promote beneficial soil microbiota; and (5) frequent tillage, herbicide use, and copper fungicides can harm populations of beneficial microbes and, in some cases, contribute to greater crop decline. Non-crop vegetation management is a viable and cost-effective means of minimizing crop decline in perennial monocultures but is in need of more direct experimental investigation in perennial agroecosystems.

Phenolics and antioxidative activities in common beans (Phaseolus vulgaris L)

Abstract: exico Abstract: Six bean cultivars grown in southern Manitoba for 2years were evaluated for variability in yield of millstreams and phenolic constituents The ethanolic extract of bean cultivars and millstreams was screened for antioxidant activity using the β-carotene-linoleate and the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) in vitro model systems Cultivar was the main source of variation for yield of millstreams, content of phenolic compounds and antioxidant activities Phenolic compounds in cultivars varied from 33 to 166mg catechin equivalent and from 015 to 032mg cyanidin-3-glucoside equivalent g −1 bean for total phenolic and anthocyanin contents, respectively The bean cultivars exhibited antioxidant activity (AA) of 10-46% inhibition of lipid peroxidation in the linoleate and 04-13 trolox equivalent antioxidant capacities (TEAC) in the DPPH model systems The hull millstream with maximum concentration of phenolic compounds exhibited the strongest antioxidant activity of 383 µM trolox equivalent g −1 hull Total phenolic content, alone or in combination with other phenolic constituents, is a potential candidate as a selection criterion for antioxidant activity in beans  2005 Society of Chemical Industry