Aging retardation strategy of PVDF membranes: evaluation of free radical scavenging effect of nano-particles

ESR and spectrophotometry proved that nano-particles can effectively remove free radicals produced by NaClO, and analyzed the mechanism of delaying aging.

Awareness about antioxidant activities of chlorogenic acid among dental students

Chlorogenic Acid (CA) is the formation of an ester established among caffeic and quinic acid. CA contains hydroxyl based groups over an aromatic moiety and exhibits very effective anticancer, antimutational and antioxidant activities. This survey was performed for assessing the awareness about antioxidant activities of CA amongst dental students. A cross-sectional survey was performed with a pretested questionnaire with ten questions disseminated among 100 dental students. The questionnaire assessed the awareness about CA therapy, their dietary sources, medicinal uses, antioxidant activity, anti ischaemic activity and free radical scavenging effect of chlorogenic acid. The responses were recorded and analyzed. 7% were aware of dietary sources,5% were aware of medical uses, 5% were aware of mechanisms of antioxidant activity, 4 % were aware of the anti ischaemic activity, and 5% were aware of the free radical scavenging effect of chlorogenic acid. Awareness about the usage of CA therapy is very less among dental students. Increased awareness programs and sensitization programs should be conducted to improve the awareness levels.

UJI ANTIOKSIDAN EKSTRAK HEKSANA, ETIL ASETAT, ETANOL, METANOL 80% DAN AIR DAUN KELOR (Moringa oleifera, Lamk)

Antioxidant Test of Hexane, Etil Asetat, Ethanol, Methanol 80% and Water Extract in Moringa oleifera Antioxidant is a substance that can protect a materials from its destruction. Sources of antioxidant could be from plants. Alkaloid compounds in the Moringa oleifera leaves have potential antioxidant source. This research aimed to examine antioxidant potential from Moringa oleifera leaves extract of hexane, ethyl acetate, methanol 80% and water . The extraction methodes was meseration, and antioxidant test used the DPPH free radical scavenging effect. The result showed that extract ethanol had the best potential antioxidant with the value of 118.19 µg/mL and R2 was 99.9%, from hexanes was 692.39 µg/mL (R2=99.9%), in ethyl acetate was 247.5 µg/mL (R2=99.9%), in methanol 80% was 121.79 µg/mL (R2= 0.998) and in water extract 189.21 µg/mL (R2=99.8%). Antioxidant standart as kuersetin that gave value of 15.84 µg/mL (R2 = 99.9%).Keywords : Bioactives compound, moringa oleifera, antioxidant ABSTRAK Antioksidan merupakan substansi yang dapat mencegah atau memperlambat kerusakan suatu zat. Sumber antioksidan dapat diperoleh dari suatu tumbuhan. Senyawa alkaloid yang terdapat pada daun kelor berpotensi sebagai sumber antioksidan. Penelitian ini bertujuan menguji antioksidan ekstrak heksana, etil asetat, etanol, metanol 80% dan air pada daun kelor (Moringa oleifera, Lamk). Penelitian dilakukan dengan menggunakan metode maserasi dan uji antioksidan menggunakan metode ”DPPH free radical scavenging effect”. Hasil uji antioksidan terbaik terdapat pada ekstrak etanol, yaitu sebesar 118.19 µg/mL dengan harga R2 sebesar 99.9%, sedangkan pelarut yang lain, yaitu pelarut heksana sebesar 692.39 µg/mL (R2=99.9%), etil asetat 247.5 µg/mL (R2=99.9%), metanol 80% 121.79 µg/mL (R2= 0.998) dan air 189.21 µg/mL (R2=99.8%), sebagai pembanding antioksidan digunakan kuersetin, yaitu 15.84 µg/mL (R2= 99.9%).Kata kunci : Senyawa bioaktif, moringa oleifera, antioksidan

Assesment of the total antioxidant capacity of apples peels during phisiological falls

The antioxidant capacity of apples peel extracts during the fruit development from three apple varieties (i.e., Ionathan, Golden Delicious and Starkrimson) were analyzed at 7, 15, 35, 65, 107, 145 days after full bloom (DAFB). The total antioxidant capacities of extracts were evaluated using free radical scavenging effect over 1,1-diphenyl l-2-picrylhydrazyl (DPPH) radical, being determined by a spectrophotometric method.The maximum antioxidant capacity was recorded in the apples harvested 7 DAFB.