Phytochemicals in human milk and their potential antioxidative protection

Diets contain secondary plant metabolites commonly referred to as phytochemicals. Many of them are believed to impact human health through various mechanisms, including protection against oxidative stress and inflammation, and decreased risks of developing chronic diseases. For mothers and other people, phytochemical intake occurs through the consumption of foods such as fruits, vegetables, and grains. Research has shown that some these phytochemicals are present in the mother’s milk and can contribute to its oxidative stability. For infants, human milk (HM) represents the primary and preferred source of nutrition because it is a complete food. Studies have reported that the benefit provided by HM goes beyond basic nutrition. It can, for example, reduce oxidative stress in infants, thereby reducing the risk of lung and intestinal diseases in infants. This paper summarizes the phytochemicals present in HM and their potential contribution to infant health

4,5-Epoxide-1,6-dimethyl-1-vinylhexyl p-coumarate: A novel monoterpene derivative from Cleistopholis patens

A novel monoterpene derivative (1) and four known partially and total acetylated tri- and tetrarhamonoside dodecanyl ether derivatives: cleistrioside-2 (2) and cleistrioside-3 (3), cleistetroside-6 (4) and cleistetroside peracetate (5) have been isolated from the fruits of Cleistopholis patens. KEY WORDS: Cleistopholis patens, Annonaceae, Oligosaccharide, Partially acetylated tri- and tetrarhamnoside dodecanyl ether derivatives, Cleistrioside, Cleistetroside, Monoterpene derivative  Bull. Chem. Soc. Ethiop. 2003, 17(2), 177-180

Pepsin digested oat bran proteins: Separation, antioxidant activity, and identification of new peptides

The aim of this study was to determine pepsin hydrolysis conditions to produce digested oat bran proteins with higher radical scavenging activities and separate and identify peptides. Isolated proteins were then digested with different concentrations of pepsin and incubation times. Hydrolysates produced with 1: 30 enzyme substrate (E/S) ratio and 2 h possessed the highest peroxyl radical scavenging activity, 608 ± 17 μM TE/g (compared to 456-474 μM TE/g for other digests), and was therefore subsequently fractionated into eight fractions (F1-F8) by high performance liquid chromatography (HPLC). F1 and F2 had little activity because of their low protein contents. Activities of F3-F8 were 447-874 μM TE/g, 20-36%, and 10-14% in the peroxyl, superoxide anion, and hydroxyl radical tests, respectively. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify a total of fifty peptides that may have contributed to the activity of F3, a fraction that better scavenged radicals

Antioxidant activity of oat proteins derived peptides in stressed hepatic hepg2 cells

The purpose of this study was to determine, for the first time, antioxidant activities of seven peptides (P1–P7) derived from hydrolysis of oat proteins in a cellular model. In the oxygen radical absorbance capacity (ORAC) assay, it was found that P2 had the highest radical scavenging activity (0.67 ± 0.02 µM Trolox equivalent (TE)/µM peptide) followed by P5, P3, P6, P4, P1, and P7 whose activities were between 0.14–0.61 µM TE/µM). In the hepatic HepG2 cells, none of the peptides was cytotoxic at 20–300 µM. In addition to having the highest ORAC value, P2 was also the most protective (29% increase in cell viability) against 2,2′ -azobis(2-methylpropionamidine) dihydrochloride -induced oxidative stress. P1, P6, and P7 protected at a lesser extent, with an 8%–21% increase viability of cells. The protection of cells was attributed to several factors including reduced production of intracellular reactive oxygen species, increased cellular glutathione, and increased activities of three main endogenous antioxidant enzymes

Synthesis and anticancer activity evaluation of some new 1,2,3,5-tetrazine derivatives attached to benzothiazole moiety

A series of novel tetrazine derivatives, containing benzothiazole framework, were prepared during the coupling reactions of some diazotized 2-aminobenzo[d]thiazole derivatives with p-acetaminophen. Their structures were elucidated based on NMR and MS spectrometry. The anticancer activity and the safety of the synthesized compounds along with the entire precursors were assessed against three human cancer cell lines and a normal cell line. All the synthesized compounds showed selective cytotoxic activity against the cancer cell lines used in comparison to the normal Vero cell line. Their IC50 values varied from 2.02 to 171.67 μM.The Cameroonian Ministry of Higher Education special research allocation, the German Academic Exchange Service (DAAD) and the University of Pretoria.https://www.arkat-usa.org/arkivoc-journalam2023Paraclinical Science

Processing Oats and Bioactive Components

Oat contains various bioactive compounds. Phenolic acids and avenanthramides, an unique group of N-cinnamoylanthranilic acid derivatives present in oat but not in other cereals have been demonstrated to reduce oxidation of low density lipoprotein cholesterol in animals and humans. Oat is also a good source of dietary fibers (i.e., beta-glucans) that have been demonstrated to reduce the risk of cardiovascular diseases. In addition, oat lipids are mostly unsaturated and the quality of proteins is higher compared to other cereals. During processing that includes cleaning, heat treatment, dehulling, flaking, and milling there is a change in concentration of these oat bioactive compounds. Other processing methods such as germination and extraction also affect the amount and activity of compounds. The magnitudes of changes taking place as a result of processing are presented in this chapter

Enzymatic hydrolysis of oat flour protein isolates to enhance antioxidative properties

Oat is an important cereal for human consumption and has relatively higher protein content compared to other cereals. Numerous studies have shown that oat polyphenols had antioxidant properties but no data is available for similar activity on proteins and peptides. The objective of this study was to investigate the antioxidant activities of tryptic and alcalase digests of oat flour protein isolates and ultra-filtered fractions. Oat flour protein hydrolysates from alcalase (APH) and trypsin (TPH) were therefore prepared and ultrafiltered using 2 and 10 kDa molecular cutoff membranes. The free radical scavenging properties were investigated by 2,2'-diphenyl-2-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, linoleic acid emulsion system and ferrous ion-chelating assays. APH and TPH significantly reduced the generation of lipid hydroperoxides resulting from autoxidation of linoleic acid after 5 days incubation. At concentration of 200:μ/L, APH and TPH also showed better chelating properties than their ultrafiltered fractions (2 kDa, 2-10 kDa). On DPPH assay recorded after 15 min alcalase fraction less than 2 kDa possessed the greater inhibition activity (32.9%) compared to 26.4% for 2 kDa trypsin fraction. The results suggest that alcalase and tryptic digests of oat flour protein can be used to produce antioxidant peptides for potential use in food products

Role of carbohydrases on the release of reducing sugar, total phenolics and on antioxidant properties of oat bran

Aqueous solutions of medium oat bran flour were treated with four carbohydrases viscozyme, celluclast, alpha-amylase, and amyloglucosidase, and then extracted with equal volume of methanol. The resulting extracts were examined for their reducing sugar content, total phenolic content (TPC), oxygen radical scavenging absorbance capacity (ORAC), hydroxyl radical scavenging effect, superoxide scavenging activity, and ferrous ion chelating potential. The amount of reducing sugar increased form 2.0% in the control sampl

Identification of peptides, metal binding and lipid peroxidation activities of HPLC fractions of hydrolyzed oat bran proteins

The aim of this study was to evaluate metal binding and antioxidant activities of hydrolyzed oat bran proteins followed by the determination of peptide sequences. Protamex oat bran protein hydrolysates (OBPH) were separated by reverse-phase HPLC into eight peptide fractions (F1–F8) and their abilities to either chelate metals (Fe2+, Ca2+) or prevent the oxidation of lipids were investigated. In the Fe2+ chelation assay, OBPH had significantly (p < 0.05) higher activity (39.7 %) than the best performed fraction F7 (22.8 %). The second most active was F5 with 12.1 % chelating activity and this was higher than the activity of the tripeptide glutathione (5.8 %) used as control. The two most Fe2+ chelating fractions (F5, F7) however had weak calcium binding (0.6–1.0 %) properties at peptide concentration ranging from 0.2 to 1.0 mg/mL. In the lipid peroxidation assay, OBPH and all HPLC fractions prevented the oxidation of linoleic acid. More than 60 peptides mainly derived from globulin and avenin proteins were identified using tandem mass spectrometry