Health‐beneficial properties of potato and compounds of interest

Potatoes have shown promising health‐promoting properties in human cell culture, experimental animal and human clinical studies, including antioxidant, hypocholesterolemic, anti‐inflammatory, antiobesity, anticancer and antidiabetic effects. Compounds present such as phenolics, fiber, starch and proteins as well as compounds considered antinutritional such as glycoalkaloids, lectins and proteinase inhibitors are believed to contribute to the health benefits of potatoes. However, epidemiological studies exploring the role of potatoes in human health have been inconclusive. Some studies support a protective effect of potato consumption in weight management and diabetes, while other studies demonstrate no effect and a few suggest a negative effect. As there are many biological activities attributed to the compounds present in potato, some of which could be beneficial or detrimental depending on specific circumstances, a long‐term study investigating the association between potato consumption and diabetes, obesity, cardiovascular disease and cancer while controlling for fat intake is needed. © 2016 Society of Chemical Industry     

Antioxidant and apoptotic potential of protein isolates derived from Vigna unguiculata (L.) Walp

Projected mortalities from cancer are expected to continue escalating, with conventional chemotherapeutic regimens having extensive side effects, hence the need for therapeutics capable of terminating cancer cells selectively, through apoptosis. Therapeutic protein isolates bind specifically to target proteins inducing cell death in vitro and in vivo in various cancer cells. Therefore, this study aimed at observing the antioxidant and anticancer potential of protein isolates from five cowpea cultivars (Glenda, Embu buff, Makhatini, Veg Cowpea 2 and Veg Cowpea 3). Cytotoxicity was conducted on cancerous and non-cancerous cell lines. Apoptosis was quantified using flow cytometry, and caspase-3/7 activity was determined. Cytotoxicity assays revealed that Embu buff was the pre-eminent inhibitor of cancerous cells, while also acting as a protecting mediator in a stressed non-cancerous cell line by causing a reversal in apoptotic activity. Therefore, cowpea isolates show high potential as candidates for the therapeutic intrusion of cancer.     

Health Benefits of Purple Corn (Zea mays L.) Phenolic Compounds

Purple corn (Zea mays L.), a grain with one of the deepest shades in the plant kingdom, has caught the attention of the food industry as it could serve as a source for alternatives to synthetic colorants. Also being rich in phenolic compounds with potential health‐promoting properties, purple corn is becoming a rising star in the novel ingredients market. Although having been widely advertised as a “healthy” food, the available information on purple corn health benefits has not yet been well reviewed and summarized. In this review, we present compositional information focused on the potential functional phenolic compounds correlated to health‐promoting effects. Studies evaluating potential health‐benefitting properties, including in vitro tests, cell models, animal and human trials, are also discussed. This paper emphasizes research using purple corn, or its extracts, but some other plant sources with similar phenolic composition to purple corn are also mentioned. Dosage and toxicity of purple corn studies are also reviewed. Purple corn phenolic compounds have been shown in numerous studies to have potent antioxidant, anti‐inflammatory, antimutagenic, anticarcinogenic, and anti‐angiogenesis properties. They were also found to ameliorate lifestyle diseases, such as obesity, diabetes, hyperglycemia, hypertension, and cardiovascular diseases, based on their strong antioxidant power involving biochemical regulation amelioration. With promising evidence from cell and animal studies, this rich source of health‐promoting compounds warrants additional attention to better understand its potential contributions to human health.     

A review on the physicochemical properties and potential food applications of cowpea (Vigna unguiculata) starch

Cowpea is a food legume with high protein and carbohydrate contents, which could be explored in addressing food and nutritional challenges in many parts of the world. However, some cowpea varieties are difficult to cook, resulting in high energy requirements and greater loss of nutrients. Since the bulk of carbohydrate in cowpea is starch, this component may be explored as an alternative starch source for various industrial applications, especially because cowpea starch is rich in resistant starch with several beneficial physiological effects. Hence, this review summarises the present knowledge on the isolation, composition, physicochemical properties and modification methods of cowpea starch. Future studies that are required to produce cowpea starch with novel properties were highlighted and the need to apply modified cowpea starch in food systems were also noted.     

BAKING PERFORMANCE AND CONSUMER ACCEPTABILITY OF RAW AND EXTRUDED COWPEA FLOUR BREADS

Cowpea flour was used to partially replace wheat flour in yeast bread, using automatic household‐type bread machines for mixing, proofing and baking. Loaves containing 15 or 30% extruded cowpea flour weighed more (683.4 g) than loaves from other treatments (641.1–652.6 g). The 100% wheat had the highest loaf volume (2.58 L) and the 30% extruded cowpea the lowest (1.64 L). Cowpea flour breads contained more protein (13.9–15.4%) than the 100% wheat (4.1% fat, 12.5% protein). Bread made with 15% extruded cowpea flour was not different (P < 0.05) from the all‐wheat control in sensory quality and acceptability. Hedonic ratings for the control and 15% extruded cowpea flour ranged from 6.6 (like slightly) to 7.4 (like moderately) for all sensory attributes. The least liked samples contained either 30% raw or 30% extruded cowpea flour, receiving ratings for all attributes ranging from 4.8 (disliked slightly) to 6.2 (liked slightly). Overall, 15% extruded cowpea flour demonstrated successful bread making performance without compromising sensory quality.     

Gamma irradiation of cowpea (Vigna unguiculata L. Walp) seeds: effect on colour,cooking quality and pasting characteristics

Cowpea seeds were treated to various gamma irradiation doses, and their colour, cooking quality and pasting properties studied. Irradiation at 50 kGy resulted in significant browning (indicated by decreases in L colour value) of cowpea seeds. At 2 and 10 (but not at 50) kGy, irradiation led to significant reduction in cooking time of cowpea seeds possibly through irradiation‐induced degradation of starch and pectic substances (indicated by decreases in peak and final viscosities) leading possibly to enhanced heat and mass transfer within the seed cotyledon and cell wall, respectively. At 50 kGy, the cooking time of cowpea seeds was prolonged significantly owing possibly to extensive polymer cross‐linking occurring within the seeds at this high dose. Splitting of cowpea cotyledons during cooking decreased significantly at 50 kGy, but was unaffected at 2 and 10 kGy. Irradiation resulted in significant leaching of nutrients from cowpea seeds during cooking in a dose‐dependent manner.     

p‐Coumaric acid and its conjugates: dietary sources,pharmacokinetic properties and biological activities

p‐Coumaric acid (4‐hydroxycinnamic acid) is a phenolic acid that has low toxicity in mice (LD₅₀ = 2850 mg kg^?1 body weight), serves as a precursor of other phenolic compounds, and exists either in free or conjugated form in plants. Conjugates of p‐coumaric acid have been extensively studied in recent years due to their bioactivities. In this review, the occurrence, bioavailability and bioaccessibility of p‐coumaric acid and its conjugates with mono‐, oligo‐ and polysaccharides, alkyl alcohols, organic acids, amine and lignin are discussed. Their biological activities, including antioxidant, anti‐cancer, antimicrobial, antivirus, anti‐inflammatory, antiplatelet aggregation, anxiolytic, antipyretic, analgesic, and anti‐arthritis activities, and their mitigatory effects against diabetes, obesity, hyperlipaemia and gout are compared. Cumulative evidence from multiple studies indicates that conjugation of p‐coumaric acid greatly strengthens its biological activities; however, the high biological activity but low absorption of its conjugates remains a puzzle. © 2015 Society of Chemical Industry     

Effect of simulated gastrointestinal digestion on phenolic composition and antioxidant capacity of cooked cowpea (Vigna unguiculata) varieties

Consumption of diets rich in phenolic compounds has been associated with reduced risk of chronic diseases. The effect of cooking and simulated gastrointestinal digestion on phenolic compounds and antioxidant properties of two cowpea (Vigna unguiculata) types was determined. Phenolic acids, flavan‐3‐ols and flavonols were the main groups of phenolic compounds identified. Cooking and simulated enzyme digestion of the cooked cowpea samples rendered some phenolics less extractable (possibly by promoting binding with other food components) or more extractable (possibly by release of bound forms). Total phenolic contents and radical scavenging properties of the cowpeas were reduced upon cooking, but increased upon simulated enzyme digestion. Cowpea extracts inhibited human LDL oxidation at a concentration of 2 mg mL^?1 possibly due to their phenolic content. Phenolic compounds in cowpea can potentially protect against cardiovascular diseases for which LDL oxidation is a risk factor.     

The Alternate Consumption of Quercetin and Alliin in the Traditional Asian Diet Reshaped Microbiota and Altered Gene Expression of Colonic Epithelial Cells in Rats

The diet of traditional Asian is similar to the Mediterranean that was considered as a healthy dietary pattern. The report was scarce on whether different plant‐derived components with similar anti‐oxidative and anti‐inflammatory function such as quercetin and alliin in traditional Asian diet consumed in an alternate style cooperatively affect health including the growth of host and the status of the gut microbiota and colonic epithelial immunity. In the present study, the effects of alternate consumption of quercetin and alliin on host health judging by the profile of gut microbiota and gene expression of colonic epithelial cells were investigated with the Illumina MiSeq sequencing (16S rRNA genes) and Illumina HiSeq (RNA‐seq) technique, respectively. The results showed that the alternate consumption significantly increased the rat body weight and reshaped the gut microbiota composition. At the phylum level, it significantly increased the relative abundance of fecal Firmicutes and Cyanobacteria but decreased that of Bacteroidetes (P < 0.05) and increased the relative abundance of Candidatus Arthromitus, Lactococcus, Geobacillus, and Ruminococcus at the genus level that benefits the host's health. The alternate consumption of quercetin and alliin also altered 13 genes expression involved in the KEGG pathways of complement and coagulation cascades and hematopoietic cell lineage to improve the gut immunity. Therefore, the alternate consumption of quercetin and alliin in traditional Asian diet can contribute beneficial metabolic effects by optimizing gut microbiota and altering the immunologic function of colonic epithelial cells, resulting in its potential to improve the sub‐health status.     

Combining selected immunomodulatory Propionibacterium freudenreichii and Lactobacillus delbrueckii strains: Reverse engineering development of an anti‐inflammatory cheese

Scope : Inflammatory bowel disease (IBD) constitutes a growing public health concern in western countries. Bacteria with anti‐inflammatory properties are lacking in the dysbiosis accompanying IBD. Selected strains of probiotic bacteria with anti‐inflammatory properties accordingly alleviate symptoms and enhance treatment of ulcerative colitis in clinical trials. Such properties are also found in selected strains of dairy starters such as Propionibacterium freudenreichii and Lactobacillus delbrueckii (Ld). We thus investigated the possibility to develop a fermented dairy product, combining both starter and probiotic abilities of both lactic acid and propionic acid bacteria, designed to extend remissions in IBD patients. Methods and results : We developed a single‐strain Ld‐fermented milk and a two‐strain P. freudenreichii and Ld‐fermented experimental pressed cheese using strains previously selected for their anti‐inflammatory properties. Consumption of these experimental fermented dairy products protected mice against trinitrobenzenesulfonic acid induced colitis, alleviating severity of symptoms, modulating local and systemic inflammation, as well as colonic oxidative stress and epithelial cell damages. As a control, the corresponding sterile dairy matrix failed to afford such protection. Conclusion : This work reveals the probiotic potential of this bacterial mixture, in the context of fermented dairy products. It opens new perspectives for the reverse engineering development of anti‐inflammatory fermented foods designed for target populations with IBD, and has provided evidences leading to an ongoing pilot clinical study in ulcerative colitis patients.     

EFFECT OF COOKING ON THE PROFILE OF PHENOLICS, TANNINS, PHYTATE, AMINO ACID, FATTY ACID AND MINERAL NUTRIENTS OF WHOLE-GRAIN AND DECORTICATED VEGETABLE COWPEA (VIGNA UNGUICULATA L. WALP)

ABSTRACT

An experiment was conducted to determine the profile of phenolics, tannins, phytate, amino acid, fatty acid and mineral nutrients in whole‐grain and decorticated vegetable cowpea before and after cooking. Two cowpea varieties: C‐152‐White, having big grain and S‐1552‐White, having small grain with black eye were used for the study. Decortication of cowpea grain resulted in significant reduction (P ≤ 0.05) of total phenolics, total tannins and phytate contents of the two cowpea varieties. Comparison showed that cooking resulted in 19, 28, 28 and 37% losses in phenolics in whole‐grain C‐152, decorticated C‐152, whole‐grain S‐1552 and decorticated S‐1552, respectively. After cooking, whole‐grain and decorticated C‐152 retained 52.1 and 57.7% tannins while S‐1552 retained 59.4 and 49.5%, respectively. In the whole grain, C‐152 lost 72.2% phytate after cooking while S‐1552 lost 70.3%. For the decorticated samples, C‐152 lost 72.4% phytate after cooking while S‐1552 lost 71.2%. For the two cowpea varieties, decortication resulted in significant (P ≤ 0.05) losses of Ca, Fe, Mn, Mg, Zn, K and Cu while there was no significant effect on protein and amino acid profile. Cooking did not cause any significant change in the mineral nutrient composition of either the whole‐grain or decorticated cowpea. For the two cowpea varieties, bulk of the fat consisted of palmitic acid (23.2–27.3%) and stearic acid (53.5–59.8%) in the ratio of 1:2, approximately. Upon cooking, losses of crude protein were recorded in the whole‐grain and decorticated samples of the two cowpea varieties.

PRACTICAL APPLICATIONS

Cowpea is an important cheap source of protein particularly for the low‐income countries, especially in Africa and Asia. However, there is the need for some pretreatments before its cooking because of the presence of some undesirable antinutrients which often cause flatulence after consumption or they can render some minerals unavailable for body assimilation. This study investigated the role that African traditional method of decortication and cooking could play in reducing the concentration of antinutritional factors. We also showed how the traditional treatments could affect the other nutritionally important component of cowpea.

     

Carob Kibble: A Bioactive‐Rich Food Ingredient

Carob (Ceratonia siliqua L.) is well known for its valuable locust bean gum obtained from the carob seeds. Separation of seeds from the pod leaves behind the carob kibble which is a good source of dietary fiber, sugars, and a range of bioactive compounds such as polyphenols and pinitol. Bioactive compounds present in carob kibble have been found to be beneficial in the control of many health problems such as diabetes, heart diseases, and colon cancer due to their antidiabetic, antioxidant, and anti‐inflammatory activities. Carob kibble has substantial potential to be used as a food ingredient. This article focuses on the composition, health benefits, and food applications of carob kibble.     

Polyphenols as active ingredients for cosmetic products

Polyphenols are secondary plant metabolites with antioxidant, anti‐inflammatory and anti‐microbial activity. They are ubiquitously distributed in the plant kingdom; high amounts contain, for example, green tea and grape seeds. Polyphenolic extracts are attractive ingredients for cosmetics and pharmacy due to their beneficial biological properties. This review summarizes the effects of polyphenols in the context of anti‐ageing activity. We have explored in vitro studies, which investigate antioxidant activity, inhibition of dermal proteases and photoprotective activity, mostly studied using dermal fibroblasts or epidermal keratinocytes cell lines. Possible negative effects of polyphenols were also discussed. Further, some physicochemical aspects, namely the possible interactions with emulsifiers and the influence of the cosmetic formulation on the skin delivery, were reported. Finally, few clinical studies, which cover the anti‐ageing action of polyphenols on the skin after topical application, were reviewed.     

Phenethyl isothiocyanate suppresses nitric oxide production via inhibition of phosphoinositide 3‐kinase/Akt‐induced IFN‐γ secretion in LPS‐activated peritoneal macrophages

Phenethyl isothiocyanate (PEITC), a constituent of many cruciferous vegetables, is well known to have versatile physiological activities, including chemopreventive effects. On the other hand, its anti‐inflammatory effects are poorly reported. Nitric oxide (NO) is associated with a wide variety of inflammatory diseases. In this study, we investigated the effects of PEITC on NO production in LPS‐activated peritoneal macrophages from ICR mice. The signaling pathway of LPS‐induced NO production was examined using neutralizing antibodies [anti‐interferon (IFN)‐γ and anti‐interleukin (IL‐12)] and specific protein kinase inhibitors, as well as others. The activity of PEITC toward NOx production was assessed in mice that received LPS via intraperitoneal administration. The neutralizing antibody of anti‐IFN‐γ, but not anti‐IL‐12, suppressed LPS‐induced NO production by 90%. LY294002, a specific inhibitor of phosphoinositide‐3‐kinase, suppressed Akt and IFN‐γ mRNA expression up‐regulated by LPS, whereas PEITC exhibited a similar inhibition profile. Furthermore, oral administration of PEITC significantly suppressed the serum concentration of NOx in ICR mice. Our results suggest that PEITC suppresses LPS‐induced NO production via inhibition of Akt activation and the resultant decrease in expression of IFN‐γ. This is one of the first reports to demonstrate a marked anti‐inflammatory effect of PEITC following its oral administration.     

Cranberry extract and quercetin modulate the expression of cyclooxygenase‐2 (COX‐2) and IκBα in human colon cancer cells

BACKGROUND: Cranberry (Vaccinium marcocarpon) fruit and quercetin, a major flavonoid found in cranberries, are likely contributors to chemoprevention, and their anti‐inflammatory activities may play a potential role in colon cancer prevention. The aim of this study was to examine the effect of cranberry extract and quercetin on basal expression of cyclooxygenase‐2 (COX‐2) and IκBα as well as the effect on phorbol 12‐myristate 13‐acetate (PMA)‐induced COX‐2 expression in colon cancer cells. RESULTS: HT‐29 human colon adenocarcinoma cells were treated with various concentrations of cranberry extract or quercetin and/or PMA, and the protein expression of COX‐2 and IκBα was determined. The results indicated that cranberry extract and quercetin decreased COX‐2 expression and suppressed degradation of IκBα in unstimulated cells. In PMA‐stimulated cells, cranberry extract was also able to decrease COX‐2 expression and suppress degradation of IκBα. CONCLUSION: The results suggest that a possible mechanism involved in the anti‐cancer activity of cranberry and quercetin is partly mediated through its anti‐inflammatory action. These findings indicate that cranberry and quercetin may reduce the risk of colon cancer possibly by suppressing inflammatory responses. Copyright © 2008 Society of Chemical Industry     

Processed Tart Cherry Products—Comparative Phytochemical Content,in vitro Antioxidant Capacity and in vitro Anti‐inflammatory Activity

Abstract: Processing of fruits and vegetables affects their phytochemical and nutrient content. Tart cherries are commercially promoted to possess antioxidant and anti‐inflammatory activity. However, processing affects their phytochemical content and may affect their related health benefits. The current study compares the in vitro antioxidant capacity and anti‐inflammatory cyclooxygenase activity of processed tart cherry (Prunus cerasus) products—cherry juice concentrate, individually quick‐frozen cherries, canned cherries, and dried cherries. Cherry products were analyzed for total anthocyanin and proanthocyanidin content and profile. On a per serving basis, total anthocyanins were highest in frozen cherries and total proanthocyanidins were highest in juice concentrate. Total phenolics were highest in juice concentrate. Juice concentrate had the highest oxygen radical absorbance capacity (ORAC) and peroxynitrite radical averting capacity (NORAC). Dried cherries had the highest hydroxyl radical averting capacity (HORAC) and superoxide radical averting capacity (SORAC). Processed tart cherry products compared very favorably to the U.S. Dept. of Agriculture‐reported ORAC of other fresh and processed fruits. Inhibition of in vitro inflammatory COX‐1 activity was greatest in juice concentrate. In summary, all processed tart cherry products possessed antioxidant and anti‐inflammatory activity, but processing differentially affected phytochemical content and in vitro bioactivity. On a per serving basis, juice concentrate was superior to other tart cherry products. Practical Application: Processing of fruits and vegetables affects their chemical and nutrient content and perhaps their related health benefits. Comparative studies are valuable to ascertain the effects of processing on fruit and vegetable chemical content and bioactivity. Here we present tart cherries as a model for this type of detailed comparison.     

Chokeberries (Aronia melanocarpa) and Their Products as a Possible Means for the Prevention and Treatment of Noncommunicable Diseases and Unfavorable Health Effects Due to Exposure to Xenobiotics

Aronia melanocarpa berries (chokeberries) constitute a very rich source of numerous substances exerting a beneficial impact on health, including mainly polyphenols (proanthocyanidins, anthocyanins, flavonoids, and phenolic acids), possessing antioxidative, anti‐inflammatory, antiviral, anticancer, antiatherosclerotic, hypotensive, antiplatelet, and antidiabetic properties. Thus, the consumption of products made from chokeberries is of vital importance for health maintenance and protection. Nowadays, due to the growing prevalence of noncommunicable diseases and ubiquitous human exposure to numerous man‐made and naturally occurring toxic substances, some of which are dangerous even at low amounts, it is very important to look for effective means of health protection. An important role in this regard may be played by A. melanocarpa berries; however, up to now the attention of scientists, nutritionists, and health practitioners has been focused mainly on the effectiveness of chokeberry products in the prevention and treatment of noncommunicable diseases, while only little attention has been paid to the possibility of their use to counteract the adverse health effects of exposure to xenobiotics. That is why in this review article the main interest has been focused on the possibility of using chokeberries in the protection against unfavorable health effects caused by the action of substances to which humans may be exposed environmentally and/or occupationally. The available experimental data indicate that not only the fruit but also the leaves of A. melanocarpa and their products may be effective means for prevention and treatment of the effects of toxic action of some xenobiotics in humans; however, further studies on this subject are necessary.