a-generalized-method-for-determining-free-soluble-phenolic-acid

A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes

Phenolic acids are a class of organic compounds that bear both a phenolic group, and a carboxylic group. They are found in grains and concentrate in the ...

University of Manitoba

Multivariate data analysis feasibility for the evaluation of Brazilian stingless bee honey (SBH) by pollen spectrum, bioactive compounds content, physicochemical, antioxidant and antimicrobial analysis was investigated. Levels of total and individual phenolics content were analyzed by HPLC-PDA. The antioxidant capacity was performed by 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), oxygen radical absorption capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. The total phenolic compounds from the thirty-two SBH was positively correlated with the antioxidant capacity. Bioactive compounds such as p-coumaric acid, quercetin, and hesperetin were identified in all the samples. Brazilian SBH shows more effective antibacterial activity against Gram-negative bacteria (E. coli and S. Typhimurium) compared to Gram-positive ones. Results also revealed that SBH could reach up to 45% higher antioxidant and biological activities than the traditional Apis mellifera honey. Chemometrics shows that chemical and biological properties of SBH have a strong relationship with the pollen botanical origin. Principal component analysis (PCA) grouped the honey into three categories with predominant pollen from Verbenaceae, Asteraceae and Sapindaceae families, confirming that SBH belonging to the same floral origin present similar characteristics.

Bioactive compounds and biological properties of Brazilian stingless bee honey have a strong relationship with the pollen floral origin.

Papaya seeds, a high source of dietary nutrients and phytochemicals are wasted when Carica papaya fruit is processed and consumed. This study investigates bioactivity of papaya seeds (PS) from 3 different locations in Kenya for potential valorization as porridge. PS was treated with acetic acid and sodium bicarbonate to improve pallatability. HPLC analysis revealed that PS flour added compounds which were absent from cornmeal (p-hydroxybenzoic, 2,4-dihydroxybenzoic and vanillic acids) and increased over 25% the pre-existing ones. Acid and alkali treatments increased the phenolic compounds content and antioxidant capacities of the seed 1 porridges in ≈19% average. The differential scanning calorimetry and the rapid visco analysis showed a significant decrease in the enthalpy required (≈44%) to gelatinize cornmeal-PS blend and the tendency for retrogradation (from 2188 to 700 cP average). Therefore, our findings indicate that PS can contribute to improved phytochemical and functional properties of cornmeal porridges.

Carica papaya seed enhances phytochemicals and functional properties in cornmeal porridges.

White rice is an important staple food globally. It is a rich source of energy but is low in dietary phenolic antioxidants. This current research aimed at providing scientific evidence for an alternative rice dish that has increased phenolic-antioxidant health-promoting potential by combining white rice with red cowpea beans and cooking with dye sorghum leaves hydrothermal extract, as a source of natural colorant. Boiled white rice and the rice-cowpea-sorghum extract dish were freeze-dried, and the free and bound phenolic compounds of raw and cooked samples were extracted. Phenolic composition, total phenolic content (TPC), and antioxidant activities (measured by 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, Trolox equivalent antioxidant capacity, and oxygen radical absorbance capacity methods) of the raw and cooked samples were determined. Combining white rice with cowpea seeds and sorghum leaves extract significantly ( < 0.0001) increased the TPC and antioxidant activities of the rice due to the higher TPC and antioxidant activities of cowpea and sorghum leaves. Although boiling caused substantial losses of flavonoids and anthocyanins in the rice-cowpea-sorghum extract composite meal, the resulting dish had higher TPC and antioxidant activities than boiled white rice. Compositing white rice with phenolic-rich pulses can be an innovative approach to providing alternative healthy rice dishes to consumers.

Phenolic Composition and Antioxidant Properties of Cooked Rice Dyed with Sorghum-Leaf Bio-Colorants.

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.

Franklin Brian Apea-Bah

Department of Food and Human Nutritional Sciences,
Richardson Centre for Functional Foods and Nutraceuticals

University of Manitoba

A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes

Franklin Brian Apea-Bah

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Food and Human Nutritional Sciences,Richardson Centre for Functional Foods and Nutraceuticals

University of Manitoba

A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes

Department of Food and Human Nutritional Sciences,
Richardson Centre for Functional Foods and Nutraceuticals