Dolores O'Riordan

Inhibition of proinflammatory biomarkers in THP1 macrophages by polyphenols derived from chamomile, meadowsweet and willow bark.

Antiinflammatory compounds in the diet can alleviate excessive inflammation, a factor in the pathogenesis of common diseases such as rheumatoid arthritis, atherosclerosis and diabetes. This study examined three European herbs, chamomile (Matricaria chamomilla), meadowsweet (Filipendula ulmaria L.) and willow bark (Salix alba L.), which have been traditionally used to treat inflammation and their potential for use as antiinflammatory agents. Aqueous herbal extracts and isolated polyphenolic compounds (apigenin, quercetin and salicylic acid, 0–100 μM) were incubated with THP1 macrophages, and interleukin (IL)‐1β, IL‐6 and tumour necrosis factor‐alpha (TNF‐α) were measured. At concentrations of 10 μM, both apigenin and quercetin reduced IL‐6 significantly ( p < 0.05). Apigenin at 10 μM and quercetin at 25 μM reduced TNF‐α significantly ( p < 0.05). Amongst the herbal extracts, willow bark had the greatest antiinflammatory activity at reducing IL‐6 and TNF‐α production. This was followed by meadowsweet and then chamomile. The lowest effective antiinflammatory concentrations were noncytotoxic (MTT mitochondrial activity assay). The Comet assay, which was used to study the protective effect of the isolated phenols against oxidative damage, showed positive results for all three polyphenols. These are the first findings that demonstrate the antiinflammatory capacity of these herbal extracts. Copyright

An In Vivo Study Examining the Antiinflammatory Effects of Chamomile, Meadowsweet, and Willow Bark in a Novel Functional Beverage

ABSTRACT The antioxidant and antiinflammatory properties of polyphenols are well documented in vitro but there are few human studies. A herbal beverage composed of chamomile, meadowsweet, and willow bark (CMW) was developed and tested for its antiinflammatory effect in a cohort of healthy adults (n = 20) during a 4-week intervention. Subjects were randomised to either the treatment (TG) or placebo group (PG). The three herbs under study, which have been used in traditional and alternative medicine, were delivered in a berry extract matrix. This berry extract was used as a control in the experiment. The objective was to assess the herbs’ effects on systemic inflammation and joint function by examining circulating cytokines and mechanical joint flexibility. Blood serum was analyzed for cytokines IL-1β, IL-6, and TNFα. There was an average decrease of 21.7% IL-1β in the treatment group, whereas the decrease seen in the placebo group was 3% but these were not statistically significant. Quartile analysis based on baseline production of TNFα demonstrated a decrease in the treatment groups IL-6 levels. This group showed improvements in mechanical joint function and pain upon movement of joints specific to the knee and lower back. Overall, no significant antiinflammatory effects were seen. The evidence is therefore inconclusive and further investigations are required using a larger cohort with some degree of elevated inflammatory activity.

In vitro evaluation of chitosan copper chelate gels as a multimicronutrient feed additive for cattle

BACKGROUND Effective micronutrient supplementation strategies are critical to ensure optimal health and productivity in livestock. The objective of this study was to develop a copper and vitamin (multimicronutrient) delivery system based on chitosan gel beads, and test its suitability, in vitro, for use as a cattle feed additive. RESULTS Chitosan was chelated with copper sulfate to produce millimetre-scale gel matrices (∼2 mm). The copper content was significantly increased (from 61 to 95 mg g by adjusting pH to alkaline conditions post bead formation. The beads could subsequently be loaded with the model vitamin riboflavin to levels as high as 324 µg g-1 beads. Restricted rehydration of the dried gel matrices in simulated rumen fluid led to a sustained release of riboflavin with no copper released in these neutral conditions for up to 24 h, demonstrating copper rumen bypass. Moreover, sustained release of the mineral was observed in abomasal conditions of pH 2 over a 3 h period. CONCLUSIONS The matrices showed rumen bypass for copper yet supplied nutritionally relevant levels of the free mineral in abomasal conditions, as required for effective supplementation in cattle. The controlled-release properties demonstrated by the matrices indicate their potential as a multimicronutrient functional feed additive to enhance cattle nutrition and productivity.

Validation of a paper-disk approach to facilitate the sensory evaluation of bitterness in dairy protein hydrolysates from a newly developed food-grade fractionation system

Casein-hydrolysates (NaCaH) are desirable functional ingredients, but their bitterness impedes usage in foods. This study sought to validate a paper-disk approach to help evaluate bitterness in NaCaHs and to develop a food-grade approach to separate a NaCaH into distinct fractions, which could be evaluated by a sensory panel. Membrane filtration generated <0.2-μm and <3-kDa permeates. Further fractionation of the <3-kDa permeate by flash-chromatography generated four fractions using ethanol (EtOH) concentrations of 5, 10, 30 and 50%. As some fractions were poorly soluble in water, the fractions were resolubilzed in EtOH and impregnated into paper-disks for sensory evaluation. Bitterness differences observed in the membrane fractions using this sensory evaluation approach reflected those observed for the same fractions presented as a liquid. The flash-chromatography fractions increased in bitterness with an increase in hydrophobicity, except for the 50% EtOH fraction which had little bitterness. Amino acid analysis of the fractions showed enrichment of different essential amino acids in both the bitter and less bitter fractions. Practical Applications The developed food-grade fractionation system, allowed for a simple and reasonably scaled approach to separating a NaCaH, into physicochemically different fractions that could be evaluated by a sensory panel. The method of sensory evaluation used in this study, in which NaCaH samples are impregnated into paper-disks, provided potential solutions for issues such as sample insolubility and limited quantities of sample. As the impregnated paper-disk samples were dehydrated, their long storage life could also be suitable for sensory evaluations distributed by mail for large consumer studies. The research, in this study, allowed for a greater understanding of the physicochemical basis for bitterness in this NaCaH. As some essential amino acids were enriched in the less bitter fractions, selective removal of bitter fractions could allow for the incorporation of the less bitter NaCaH fractions into food products for added nutritional value, without negatively impacting sensory properties. There is potential for this approach to be applied to other food ingredients with undesirable tastes, such as polyphenols.

Peptidomic screening of bitter and nonbitter casein hydrolysate fractions for insulinogenic peptides

Sodium caseinate hydrolysates (NaCaH) contain biologically active peptides that can positively influence human health. However, their intense bitterness hinders their inclusion in food products. To our knowledge, no studies have investigated whether a correlation between bitterness and bioactivity exists in NaCaH, so it is not yet known what effect selective removal of bitterness has on NaCaH bioactivity. A deeper understanding of the physicochemical characteristics affecting both bitterness and bioactivity is therefore needed. The aim of this study was to use in silico analysis to elucidate the relationship between bitterness and bioactivity of the insulinogenic NaCaH. The NaCaH fractions were generated by membrane filtration and flash chromatography and were subsequently evaluated for bitterness by a sensory panel. In this present study, peptidomic and bioinformatic processing of these NaCaH fractions allowed for the identification of insulinogenic peptides as well as other literature-identified peptides in each of the fractions. The results showed that the most bitter fraction contained the highest abundance of insulinogenic peptides, whereas another bitter fraction contained the highest abundance of other literature-identified bioactive peptides exhibiting angiotensin-converting enzyme-inhibition activity. Although some bioactive peptides were identified in the least bitter fractions, the abundance of these peptides was very low. These observations show a correlation between bitter taste and bioactivity, highlighting potential complications in removing bitterness while maintaining bioactivity. However, as the most bitter fraction contained the highest abundance of insulinogenic peptides, there is potential for using a lower dose of this enriched bioactive fraction to exert health benefits. The second most bitter fraction contained a very low abundance of insulinogenic peptides and other bioactive peptides. Therefore, removal of this fraction could reduce the NaCaH products bitterness without significantly altering overall bioactive potential.

Monitoring the progression of calcium and protein solubilisation as affected by calcium chelators during small-scale manufacture of casein-based food matrices

Calcium and protein solubilisation during small-scale manufacture of semi-solid casein-based food matrices was investigated and found to be very different in the presence or absence of calcium chelating salts. Calcium concentrations in the dispersed phase increased and calcium-ion activity (ACa++) decreased during manufacture of the matrices containing calcium chelating salts; with ∼23% of total calcium solubilised by the end of manufacture. In the absence of calcium chelating salts, these concentrations were significantly lower at equivalent processing times and remained unchanged as did ACa++, throughout manufacture. The protein content of the dispersed phase was low (≤3% of total protein), but was significantly higher for matrices containing calcium chelating salts. This study elucidates the critical role of calcium chelating salts in modulating casein hydration and dispersion and gives an indication of the levels of soluble calcium and protein required to allow matrix formation during manufacture of casein-based food structures e.g. processed and analogue cheese.