Phenolic Acids, Antioxidant Capacity, and Estimated Glycemic Index of Cookies Added with Brewer's Spent Grain.

Brewers' spent grain (BSG) is the major by-product of the brewing industry, with great potential as a functional ingredient due to its bioactive compounds. Thus, BSG could be suitable for improving the low nutritional quality of wheat-based snacks highly consumed by young people. The objective of this study was to substitute wheat flour with BSG (0, 10, 20, and 30%) for cookies elaboration, and evaluate the dough rheology, phenolic acids, antioxidant capacity, arabinoxylans content and proximate composition of the cookies Protein content and bioactive compounds (ferulic and p-coumaric acids, water unextractable arabinoxylans) of cookies significantly (p < 0.05) increased with the substitution level. In comparison to the wheat-alone cookies, the 20% BSG-containing cookies showed a lower hydrolysis and glycemic index (GI), and less total starch. The low cost, protein-rich BSG with antioxidant capacity improves the nutritional quality of cookies and may confer health benefits beyond basic nutrition.

The physicochemical and structural properties and in vitro digestibility of pea starch isolated from flour ground by milling and air classification.

The fine, coarse and parent starches were isolated from pea flour by milling and air-classification. Their structural, thermal, physicochemical properties and in vitro digestibility were investigated. Particle Size Distribution showed the fine starch with the smallest unimodal distribution (18.33 and 19.02 µm) displayed higher degree of short-range molecular order and lower number of double helix structure. Scanning Electron Microscopy showed the morphology of the coarse starch granules as uniform in size and lacking protein particles on its smooth surface. Differential Scanning Calorimetry revealed the coarse starch had higher enthalpy changes while Rapid Visco Analysis showed higher peak, trough, and breakdown viscosities for the fine starch. In vitro digestibility featured the fine starch containing lower fast digesting starch contents, but with higher resistant starch content, indicating its resistance to enzymatic hydrolysis. The results could provide theoretical support for application of pea starch in functional foods and the manufacture of emerging starch products.

Effect of cooking duration on carotenoid content, digestion and potential absorption efficiencies among refined semolina and whole wheat pasta products.

The bioaccessibility of carotenoids varies among different foods due to factors such as food matrix composition and type or extent of processing. Hence it is important to understand the extent to which these factors influence carotenoid bioaccessibility after the consumption and digestion of food. This study evaluated the carotenoid content, micellization efficiency, digestive stability, antioxidant activity and bioaccessibility of carotenoids as impacted by wheat cultivar and cooking duration among whole wheat flour (WWF) and refined semolina (RS) pasta. WWF and RS pasta were processed from three durum wheat cultivars (AAC Spitfire, CDC Precision, and Transcend) and cooked to al dente (Al), fully cooked (FCT) or overcooked (OC). The study showed that the wheat cultivar and cooking duration were significant functions of bioaccessible lutein in RS samples while only the cultivar influenced the bioaccessibility of zeaxanthin and lutein in WWF samples. In both WWF and RS, the effect of the cultivar on the bioaccessibility of lutein and zeaxanthin was similar and was as follows: Transcend > CDC Precision > AAC Spitfire. Cooking to Al significantly caused an increment in bioaccessible lutein in RS samples regardless of the wheat cultivar. This influence of cooking duration (Al > FCT > OC) was inversely related to the lutein concentrations in undigested pasta (OC = FCT > Al). DPPH scavenging activity among WWF samples was about 2-fold greater or more than that of RS samples regardless of the cultivar or cooking duration before and after digestion. Our data suggest that the effect of wheat cultivar and cooking duration modulates the bioaccessibility and antioxidant activity of RS and WWF pasta products.

Effect of simulated in vitro upper gut digestion of processed cowpea beans on phenolic composition, antioxidant properties and cellular protection.

The effect of simulated in vitro upper gut digestion on the phenolic composition and antioxidant properties of processed cowpea beans was studied. The samples comprised four cowpea cultivars: a cream, brownish-cream and two reddish-brown cultivars. Dry cowpea seeds were soaked in water, blended into paste and deep-fried in vegetable oil. The fried samples were taken through in vitro upper gut digestion followed by freeze-drying of the supernatant. Phenolic composition of extracts from the supernatants were determined using HPLC-MS. Radical scavenging activities were documented using the TEAC, ORAC and nitric oxide (NO) assays. In vitro digestion of the processed cowpeas resulted in phenolic-peptide complexes that were identified for the first time, and decreased extractable phenolic compounds. However, the radical scavenging activities increased. The processed cowpeas and their digests inhibited cellular NO production, and oxidative DNA and cellular damage. In conclusion, deep-fried cowpeas when consumed, could potentially help alleviate oxidative stress-related conditions.

Hydrothermal extraction, a promising method for concentrating phenolic antioxidants from red osier dogwood (Cornus stolonifer) leaves and stems.

Red osier dogwood (ROD) (Cornus stolonifer) is a popular ornamental shrub in most parts of North America. It has a record of ethnopharmacological uses by native North Americans. With increasing awareness about the health benefits of natural antioxidants, efforts are needed to develop methods for producing plant-based antioxidants as sources of nutraceuticals or functional food ingredients. This study aimed at establishing an optimum temperature for hydrothermal extraction of phenolic compounds from the leaves and stems of ROD. Spray-dried extracts obtained from hydrothermal extraction at four different temperatures, as well as their raw materials and spent residue were analyzed for moisture content and water activity. The samples were extracted with organic solvent and their total phenolic content, phenolic composition and antioxidant activity were also determined. Moisture content was below 10% and the water activity was below 0.6 inclusive, which are recommended for storing dry plant products. Glucogallic acid, ellagic acid, rutin, quercetin 3-O-malonylglucoside and quercetin were the phenolic compounds identified in all the samples. Rutin was the predominant compound. As expected, all the spray-dried extracts had higher phenolic content and antioxidant activity than the raw materials and spent materials. Among the temperatures studied, 98 °C was the most effective in extracting the phenolic compounds. The spray-dried extracts may find application in high-value antioxidant-rich products such as functional food ingredients and nutraceuticals. The spent materials retained a considerable amount of phenolic antioxidants and can therefore be useful in preparing antioxidant-rich animal feed.

Hydroxycinnamic acid amide (HCAA) derivatives, flavonoid C-glycosides, phenolic acids and antioxidant properties of foxtail millet.

The profiles of phenolic compounds and antioxidant properties of dehulled foxtail millets were studied. Twenty-one phenolics were detected in the free fraction, including a series of nine hydroxycinnamic acid spermidines reported for the first time and three flavonoid C-glycosides of kaempferol and apigenin. Twenty-three phenolic acid derivatives were detected in the bound fraction with ferulic acid being the predominant phenolic acid, as well as four ferulic acid dimers (DFAs) reported for the first time in foxtail millet. Total phenolic contents (TPC) of free and bound fractions varied from 161.86 to 224.47 mg ferulic acid equivalent (FAE)/kg DW, 170.69 to 294.75 mg FAE/kg DW, respectively. Antioxidant activities, based on the DPPH, ABTS+ and ORAC assays, were determined for all extracts related to TPC. Dehulled foxtail millet contains a diverse profile of phenolic compounds potentially suitable for development of functional foods with unique antioxidant properties.

Profile of phenolic compounds and antioxidant activity of finger millet varieties.

The profiles of phenolic compounds and antioxidant capacities of four finger millet varieties harvested in northern Malawi were investigated. The total phenolics, flavonoids and condensed tannins in the free fractions ranged from 114.43 to 179.19 mg ferulic acid equivalent (FAE)/100 g, 90.24 to 202.94 mg catechin equivalent (CE)/100 g and 31.76 to 83.59 mg CE/100 g, respectively. Total phenolic contents of the bound fractions ranged from 58.27 to 123.23 mg FAE/100 g. Twenty phenolic compounds were identified in the free fractions including eighteen flavonoids, with catechin and epicatechin being the predominant flavonoids. Seventeen phenolic compounds were identified in the bound fractions, with ferulic acid being the predominant one. Ten of the identified polyphenols were firstly reported in finger millet. Darker colored finger millet varieties had higher phenolic contents and antioxidant properties than the lighter colored ones. Finger millet can be used as healthy food material and natural antioxidant resource.

Germinated Brown Rice Attenuates Atherosclerosis and Vascular Inflammation in Low-Density Lipoprotein Receptor-Knockout Mice.

The present study investigates the impact of germinated brown rice (GBR) on atherosclerosis and the underlying mechanism in low-density lipoprotein receptor-knockout (LDLr-KO) mice. The intensity of atherosclerosis in aortas of LDLr-KO mice receiving diet supplemented with 60% GBR (weight/weight) was significantly less than that in mice fed with 60% white rice (WR) or control diet ( p < 0.05); all diets contained 0.06% cholesterol. WR or GBR diet did not significantly alter plasma total or LDL-cholesterol, fecal sterols, or glucose, or the activities of antioxidant enzymes, compared to the control diet. The adhesion of monocytes to aortas from LDLr-KO mice fed with WR diet was significantly more than that from mice receiving the control diet ( p < 0.01). GBR diet decreased monocyte adhesion to aortas compared to WR diet ( p < 0.01). GBR diet also reduced the levels of plasminogen activator inhibitor-1 (PAI-1), monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor-α (TNF-α) in plasma, and the abundances of MCP-1, PAI-1, TNF-α, intracellular cell adhesion molecule-1, toll-like receptor-4, PAI-1, LDLr-like protein, and urokinase plasminogen activator and its receptor in aortas or hearts from LDLr-KO mice in comparison to the WR diet ( p < 0.05, 0.01, respectively). The findings suggest that GBR administration attenuated atherosclerosis and vascular inflammation in LDLr-KO mice compared to WR. The anti-atherosclerotic effect of GBR in LDLr-KO mice at least in part results from its anti-inflammatory activity.

Phenolic composition and antioxidant properties of koose, a deep-fat fried cowpea cake.

Koose, a West African delicacy, is a side dish prepared by deep frying thick cowpea paste. The current research determined the effect of deep-fat frying of cowpea paste on its total phenolic content (TPC), phenolic composition and antioxidant properties. Four cowpea cultivars comprising two reddish-brown, a brownish-cream and cream phenotypes were used. Liquid chromatography-mass spectrometry was used to determine phenolic composition of the samples. TPC was determined using Folin-Ciocalteu method while radical scavenging capacities were by Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity and nitric oxide scavenging assays. The phenolic acids identified included benzoic and cinnamic acid derivatives. The predominant flavonoid classes were flavan-3-ols and flavonols. Deep-fat frying of the cowpea pastes decreased their TPC, radical scavenging capacities and total quantified flavonoids. The koose inhibited radical-induced oxidative cellular and DNA damage. It is concluded that koose is a potential functional food that can contribute to alleviating radical-induced oxidative stress.

Inhibitory Effects of North American Wild Rice on Monocyte Adhesion and Inflammatory Modulators in Low-Density Lipoprotein Receptor-Knockout Mice.

The present study examined the effects of wild rice on monocyte adhesion, inflammatory and fibrinolytic mediators in low-density lipoprotein receptor-knockout (LDLr-KO) mice. Male LDLr-KO mice received a cholesterol (0.06%, w/w)-supplemented diet with or without white or wild rice (60%, w/w) for 20 weeks. White rice significantly increased monocyte adhesion and abundances of monocyte chemoattractant protein-1, tissue necrosis factor-α, intracellular cell adhesion molecule-1, plasminogen activator inhibitor-1, urokinase plasminogen activator (uPA), and uPA receptor in aortae and hearts of LDLr-KO mice compared to the control diet. Wild rice inhibited monocyte adhesion to the aorta, atherosclerosis, and abundances of the inflammatory and fibrinolytic regulators in the cardiovascular tissue of LDLr-KO mice compared to white rice. White or wild rice did not significantly alter the levels of cholesterol, triglycerides, or antioxidant enzymes in plasma. The anti-atherosclerotic effect of wild rice may result from its inhibition on monocyte adhesion and inflammatory modulators in LDLr-KO mice.

Sorghum-cowpea composite porridge as a functional food, Part II: Antioxidant properties as affected by simulated in vitro gastrointestinal digestion.

The effect of compositing red non-tannin sorghum with brownish-cream cowpea and in vitro gastrointestinal digestion on total phenolic and flavonoid contents and antioxidant properties of a sorghum-cowpea composite porridge was studied. Maize-soybean composite porridge was used as a reference sample. Antioxidant properties were studied using radical scavenging activities against the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), peroxyl and NO radicals as well as inhibition of low density lipoprotein (LDL) oxidation and oxidative damage of vector DNA. Hydroperoxide content of the samples was also measured. All the samples demonstrated radical scavenging activity. Simulated duodenal digests of the porridges had hydroperoxides and therefore caused LDL oxidation. The undigested porridges and simulated gastric digests inhibited LDL oxidation. Compositing the cereals with legumes increased total phenolic and flavonoid contents and NO scavenging activity of their porridges. In vitro gastrointestinal digestion of the porridges increased their total phenolic and flavonoid contents, radical scavenging activities and LDL oxidation inhibitory activity.

Does a sorghum-cowpea composite porridge hold promise for contributing to alleviating oxidative stress?

The effect of compositing red non-tannin sorghum with cream-coloured cowpea and porridge preparation on phenolic profile and radical scavenging activity was studied. A maize-soybean composite porridge representing a similar product on the South African market was used as reference sample. UPLC-QToF-MS-ESI was used to determine phenolic composition of the grain flours, their composites and porridges. Total phenolic content was determined using Folin-Ciocalteu method while radical scavenging activity was determined using the ABTS, DPPH and NO radical scavenging assays. Four benzoic acid derivatives and five cinnamic acid derivatives were identified in the samples. The predominant flavonoid subclasses identified in sorghum were flavan-3-ols, flavanones and flavones while cowpea had mainly flavan-3-ols and flavonols with soybean having mainly isoflavones. Compositing the cereals with legumes significantly (p<0.01) increased their total flavonoid content and radical scavenging activities. Sorghum-cowpea composite porridge showed better promise in contributing to alleviating radical induced oxidative stress than maize-soybean composite porridge.