Antioxidant-rich fractions were extracted from pomegranate (Punica granatum) peels and seeds using ethyl acetate, methanol, and water. The extracts were screened for their potential as antioxidants using various in vitro models, such as beta-carotene-linoleate and 1,1-diphenyl-2-picryl hydrazyl (DPPH) model systems. The methanol extract of peels showed 83 and 81% antioxidant activity at 50 ppm using the beta-carotene-linoleate and DPPH model systems, respectively. Similarly, the methanol extract of seeds showed 22.6 and 23.2% antioxidant activity at 100 ppm using the beta-carotene-linoleate and DPPH model systems, respectively. As the methanol extract of pomegranate peel showed the highest antioxidant activity among all of the extracts, it was selected for testing of its effect on lipid peroxidation, hydroxyl radical scavenging activity, and human low-density lipoprotein (LDL) oxidation. The methanol extract showed 56, 58, and 93.7% inhibition using the thiobarbituric acid method, hydroxyl radical scavenging activity, and LDL oxidation, respectively, at 100 ppm. This is the first report on the antioxidant properties of the extracts from pomegranate peel and seeds. Owing to this property, the studies can be further extended to exploit them for their possible application for the preservation of food products as well as their use as health supplements and neutraceuticals.

http://www.pkdiet.com/pdf/pomegranate/pomegranateAntioxidant.pdf

Studies on the Antioxidant Activity of Pomegranate (Punica granatum) Peel and Seed Extracts Using in Vitro Models

Cinnamon zeylanicum bark extract and powder mediated green synthesis of nano-crystalline silver particles and its bactericidal activity.

Antibacterial and antioxidant activities of grape (Vitis vinifera) seed extracts

Functional properties of coffee and coffee by-products

Bioavailability is a key step in ensuring bioefficacy of bioactive food compounds or oral drugs. Bioavailability is a complex process involving several different stages: liberation, absorption, distribution, metabolism and elimination phases (LADME). Bioactive food compounds, whether derived from various plant or animal sources, need to be bioavailable in order to exert any beneficial effects. Through a better understanding of the digestive fate of bioactive food compounds we can impact the promotion of health and improvement of performance. Many varying factors affect bioavailability, such as bioaccessibility, food matrix effect, transporters, molecular structures and metabolizing enzymes. Bioefficacy may be improved through enhanced bioavailability. Therefore, several technologies have been developed to improve the bioavailability of xenobiotics, including structural modifications, nanotechnology and colloidal systems. Due to the complex nature of food bioactive compounds and also to the different mechanisms of absorption of hydrophilic and lipophilic bioactive compounds, unravelling the bioavailability of food constituents is challenging. Among the food sources discussed during this review, coffee, tea, citrus fruit and fish oil were included as sources of food bioactive compounds (e.g. (poly)phenols and polyunsaturated fatty acids (PUFAs)) since they are examples of important ingredients for the food industry. Although there are many studies reporting on bioavailability and bioefficacy of these bioactive food components, understanding their interactions, metabolism and mechanism of action still requires extensive work. This review focuses on some of the major factors affecting the bioavailability of the aforementioned bioactive food compounds.

/pdf/bioavailability-of-bioactive-food-compounds-a-challenging-16dm46vhv0.pdf

Bioavailability of bioactive food compounds: a challenging journey to bioefficacy

Antioxidant activities of flavidin in different in vitro model systems.

Lichen, Parmotrema stuppeum (P. stuppeum) was successively extracted with benzene and acetone. Both the extracts were fractionated on 1% oxalic acid impregnated silica gel column to obtain four phenolic compounds. The structures of compounds were identified by 1H and 13C NMR spectra as methyl orsenillate, orsenillic acid, atranorin and lecanoric acid respectively. Antioxidant activity of benzene extract, acetone extract and isolated compounds were evaluated in a beta-carotene-linoleate model system. The pure compounds showed moderate antioxidant activity. This is the first report on the isolation and characterisation of compounds from the lichen P. stuppeum as well as on their antioxidant activity.

https://www.degruyter.com/downloadpdf/j/znc.2000.55.issue-11-12/znc-2000-11-1227/znc-2000-11-1227.xml

Phenolic Constituents from the Lichen Parmotrema stuppeum (Nyl.) Hale and Their Antioxidant Activity

Coffee, consumed for its refreshing and stimulating effect, belongs to the tribe Coffea of the subfamily Cinchonoidea of Rubiaceae family. Coffee is a complex chemical mixture composed of several chemicals. It is responsible for a number of bioactivities and a number of compounds accounting for these effects. Few of the significant bioactivities documented are antioxidant activity, anticarcinogenic activity, antimutagenic activity etc. Various compounds responsible for the chemoprotective effects of coffee are mainly polyphenols including chlorogenic acids and their degradation products. Others include caffeine, kahweol, cafestol, and other phenolics. Coffee also shows protective or adverse effects on various systems like the skeletal (bone) system, the reproductive system, the nervous system, the cardiovascular system, the homocysteine levels, the cholesterol levels etc. Harmful effects of coffee are associated with people who are sensitive to stimulants. Overall, with the available information, it can be concluded that the moderate consumption, corresponding to 3 to 4 cups/day with average strength is safer to human health.

A Perception on Health Benefits of Coffee

The hydro-distilled volatile oil of the Cinnamomum zeylanicum (C. zeylanicum) buds was analyzed using GC and GC-MS for the first time. Thirty-four compounds representing approximately 98% of the oil was characterized. It consists of terpene hydrocarbons (78%) and oxygenated terpenoids (9%). alpha-Bergamotene (27.38%) and alpha-copaene (23.05%) are found to be the major compounds. A comparison of the chemical composition of the oil was made with that of flowers and fruits.

/pdf/chemical-composition-of-volatile-oil-from-cinnamomum-1svobv7o7s.pdf

Lingamallu Jagan Mohan Rao

Papers

Antioxidant activities of flavidin in different in vitro model systems.

Phenolic Constituents from the Lichen Parmotrema stuppeum (Nyl.) Hale and Their Antioxidant Activity

A Perception on Health Benefits of Coffee

Chemical Composition of Volatile Oil from Cinnamomum zeylanicum Buds

Chemical composition of volatiles from coconut sap (neera) and effect of processing