Antioxidant effect of humic acids on rat hepatocytes

The antioxidant properties of humic acids of various origins have been investigated (from bio-humus, black soil from Ternopil region, and peat from different regions, such as: Velykyi Liubin, Drohobych and Belarus Republic). Titrimetric analysis has been shown the quantitative composition of the acidic functional groups of the obtained humic acids. According to the data of thermogravimetric analysis, the values of parameters, showing the ratio of their aliphatic to the cyclic part were determined. It was found that all obtained humic acids are characterized by high antioxidant activity: the formation of thiobarbituractive products and carbonyl groups of proteins in liver hepatocytes were decreased. The inhibition of the products of free radical formation of lipid components and proteins was better inhibited by 1% solutions of humates from vermicompost and humic acids from peat. The results indicate prospects of the humic acids for creating the means of restoring the physiological functions of biological objects in pathological conditions under conditions of free radical stress for application in cosmetic pharmaceutical products.

Dietary Phytochemicals: As a Natural Source of Antioxidants

Since time immemorial, plants are used as the source of food and medicine. It can be traced back to the start of humanity. Bringing plant-based food, such as fruits, vegetables, and whole grains, rich in phytochemicals, with beneficial nutrients, opens the door for healthy living. The health benefits are partly attributed to the compounds which possess antioxidants. Several epidemiological observations have shown an opposite relationship between consumption of plant-based foods, rich in phytochemicals, and many diseases including cancer. The majority of the ailments are related to oxidative stress induced by free radicals. Free radicals are extremely unstable with a very short half-life, highly reactive molecule which leads to oxidative damage to macromolecules such as proteins, DNA, and lipids. Free radical induced cellular inflammation appears to be a major contributing factor to cause aging, and degenerative diseases such as cancer, cardiovascular diseases, diabetes, hepatic diseases, renal ailments, and brain dysfunction. Free radicals have been caught up in the pathogenesis of several diseases. Providentially, free radical formation is controlled naturally by phytochemicals, through their antioxidant potential which plays a key role in preventing many diseases including cancer by suppressing oxidative stress-induced DNA damage. Keeping these facts in mind, an attempt has been made to highlight the oxidative stress, enzymatic and non-enzymatic antioxidant, dietary phytochemicals and their role of in disease prevention and cure.

UJI FITOKIMIA KAPASITAS ANTIOKSIDAN DAN PENGARUH PEMBERIAN EKSTRAK DAUN BERENUK CRESCENTIA CUJETE TERHADAP KADAR MDA OTAK DAN DARAH TIKUS SPRAGUE DAWLEY YANG DIINDUKSI HIPOKSIA NORMOBARIK SISTEMIK KRONIS

Hipoksia adalah suatu kondisi ketika konsentrasi oksigen dalam sel rendah. Kondisi ini dapat meningkatkan pembentukan radikal bebas yang mengarah ke keadaan stres oksidatif yang menghasilkan peroksidasi lipid yang mengakibatkan berbagai kerusakan makromolekul yang dapat merusak otak. Karena itu, tubuh membutuhkan antioksidan untuk mencegah kerusakan tersebut. Salah satu sumber antioksidan eksogen adalah daun Calabash. Penelitian ini bertujuan untuk menentukan kapasitas antioksidan serta konstituen fitokimia daun Berenuk dan menentukan pengaruh ekstrak daun Berenuk dalam menurunkan kadar MDA total dalam darah dan otak tikus Sprague-Dawley yang diinduksi oleh sistemik kronis. hipoksia. Ekstraksi dilakukan dengan metode maserasi menggunakan pelarut etanol. Kapasitas antioksidan dievaluasi dengan uji radikal bebas DPPH. 32 tikus Sprague-Dawley dibagi menjadi 4 kelompok (normoksia, hipoksia 3 hari, 7 hari dan 14 hari (O2 8%; N2 92%)). Setiap kelompok kemudian dibagi lagi menjadi 2 subkelompok (diberikan ekstrak daun dan tidak pemberian). Ekstrak diberikan 400 mg / kg berat badan selama 14 hari. Evaluasi kadar MDA di otak dan darah dilakukan dengan menggunakan metode Wills. Kapasitas Antioksidan Berenuk dengan IC50 = 158,46 μg/mL Semakin lama tikus diinduksi oleh hipoksia sistemik kronis, semakin tinggi kadar MDA dalam darah dan otak. Ada penurunan yang signifikan kadar MDA otak dan darah tikus yang diberi ekstrak daun dibandingkan dengan kelompok yang tidak diberi. Ekstrak Berenuk menurunkan kadar MDA dalam darah dan otak yang disebabkan oleh hipoksia sistemik kronis. Hypoxia is a condition when oxygen concentration in cell is low. This condition can increase free radical formation that leads to oxidative stress state and cause peroxidation of lipid resulting in various macromolecule damages that damage the brain. Thus, the body needs antioxidant to prevent those damage. One of the exogen antioxidant source is calabash leaf. This study aimed to determine the antioxidant capacity as well as the phytochemical constituent of Calabash leaves and determining the effect of Calabash leaves extract in decreasing total MDA levels in the blood and brain of the Sprague-Dawley rats that were induced by chronic systemic hypoxia. Extraction was performed by maceration method using ethanol solvent. Antioxidant capacity was evaluated by DPPH radical scavenging assay. 32 Sprague-Dawley rat were divided into 4 groups (normoxia, 3 days, 7 days and 14 days of hypoxia (O2 8%;N2 92%)). Each group then divided again into 2 subgroups (given leaves extract administration and not). The extract administrated 400 mg/kg body weight for 14 days. The evaluation of MDA levels in the brain and blood was performed by using Wills method. Antioxidant capacity Calabash with IC50 = 158,46 μg/mL The longer the rats were induced by chronic systemic hypoxia, the higher MDA levels in the blood and brain. There was significant decreases in brain and blood MDA levels of rats given leaf compared with the group that was not given. The calabash leaves preventrise of MDA levels in the blood and brain induced by chronic systemic hypoxia

Hydrogen Peroxide Effects on Natural-Sourced Polysacchrides: Free Radical Formation/Production, Degradation Process, and Reaction Mechanism—A Critical Synopsis

Numerous reactive oxygen species (ROS) entities exist, and hydrogen peroxide (H2O2) is very key among them as it is well known to possess a stable but poor reactivity capable of generating free radicals. Considered among reactive atoms, molecules, and compounds with electron-rich sites, free radicals emerging from metabolic reactions during cellular respirations can induce oxidative stress and cause cellular structure damage, resulting in diverse life-threatening diseases when produced in excess. Therefore, an antioxidant is needed to curb the overproduction of free radicals especially in biological systems (in vivo and in vitro). Despite the inherent properties limiting its bioactivities, polysaccharides from natural sources increasingly gain research attention given their position as a functional ingredient. Improving the functionality and bioactivity of polysaccharides have been established through degradation of their molecular integrity. In this critical synopsis; we articulate the effects of H2O2 on the degradation of polysaccharides from natural sources. Specifically, the synopsis focused on free radical formation/production, polysaccharide degradation processes with H2O2, the effects of polysaccharide degradation on the structural characteristics; physicochemical properties; and bioactivities; in addition to the antioxidant capability. The degradation mechanisms involving polysaccharide’s antioxidative property; with some examples and their respective sources are briefly summarised.

Effects of high and low frequency ultrasound on the production of volatile compounds in milk and milk products – a review

The effects of low and high frequency ultrasound on the production of volatile compounds along with their derivation and corresponding off-flavours in milk and milk products are discussed in this review. The review will simultaneously discuss possible mechanisms of applied ultrasound and their respective chemical and physical effects on milk components in relation to the production of volatile compounds. Ultrasound offers potential benefits in dairy applications over conventional heat treatment processes. Physical effects enhance the positive alteration of the physicochemical properties of milk proteins and fat. However, chemical effects propagated by free radical generation cause redox oxidations which in turn produce undesirable volatile compounds such as aldehydes, ketones, acids, esters, alcohols and sulphur, producing off-flavours. The extent of volatile compounds produced depends on ultrasonic processing conditions such as sonication time, temperature and frequency. Low frequency ultrasound limits free radical formation and results in few volatile compounds, while high ultrasonic frequency induces greater level of free radical formation. Furthermore, the compositional variations in terms of milk proteins and fat within the milk systems influence the production of volatile compounds. These factors could be controlled and optimized to reduce the production of undesirable volatiles, eliminate off-flavours, and promote the application of ultrasound technology in the dairy field.

STUDY ON THE SYNTHESIS OF AMINOALCOHOL VIA REACTION BETWEEN ALDEHYDE AND IMINE BY SAMARIUM (II) IODIDE CATALYST

Samarium (II) iodide (SmI2) has become one of the common, effective catalysts for coupling reactions between carbonyl compounds to form 1,2-diol by initiating free radical formation. In this paper, we present the results of studying the role of SmI2 catalyst on the aza-pinacol coupling reaction between aldehyde and imine under different mole ratios of SmI2, temperature and solvent conditions. The results showed that, in the THF solvent, at -78 °C, with 2.0 mole equivalent of the SmI2 catalyst, the reaction of pinacol coupling produces 1,2-aminoalcohols with efficiency of up to 91% yield and limited 1,2-diol by product.