Antioxidants in mangrove plants and endophytic fungal associations

Abstract

The manner in which fungal endophytes activate host stress response systems is unknown; the occurrence of additional mechanisms involved in symbiotically-conferred stress tolerance in mangrove plants (the primary producers of estuarine food chain) is also an unresolved issue. Here, we report antioxidant potentials of four different mangroves and their endophytic fungi. We elucidated the possible roles of antioxidants in symbiotic association between mangroves and their endophytic fungi. Four different mangrove species and the predominant endophytic fungus Aspergillus flavus were analyzed using various in vitro assay systems (such as iron chelating capacity, reducing power, and hydroxyl radicals/hydrogen peroxide/l-diphenyl-2-picrylhydrazyl radical scavenging and inhibition of lipid peroxidation using the β-carotene–linoleate model system). In vitro models clearly established the antioxidant potency of extracts of mangrove plants and their respective endophytic fungi, which aids in understanding the mutualistic associations of plant and endophyte against various biotic and abiotic stresses. Re-infection analysis of endophytic A. flavus in tobacco plants confirmed the endophytic status of the fungus and its enhancement effect on plant growth.

Evaluation of In Vitro Antidiabetic and Antioxidant Activities and Preliminary Phytochemical Screening of Leaf Extracts of Avicennia officinalis

“…The IC 50 values for DPPH scavenging activities of PEL and AQL were reported as 0.25 and 0.43 mg/ml. The present finding also corroborated the earlier study of Ravindran et al [16] that reported the DPPH radical scavenging potential of methanol leaf extracts of A. officinalis with the EC 50 value of 0.239 mg/ml.…”

“…The IC 50 value for AQL and PEL were recorded as 0.17 and 0.48 mg/ml respectively. Earlier study also showed that the methanol leaf extracts of A. officinalis exhibited hydrogen peroxide scavenging activity with IC 50 value of 0.378 mg/ml [16].…”

Endophytic fungi associated withTaxus fuana(West Himalayan Yew) of Pakistan: potential bio-resources for cancer chemopreventive agents

“…The most potent activity was observed with NFW3 (an IC 50 value of 11.7 lg/mL). Antioxidant potential has been reported previously with organic extracts of other fungal endophytes such as Phomopsis, Xylaria and Colletotrichum (Joseph & Priya 2011;Tianpanich et al 2011;Ravindran et al 2012;Wu et al 2013). In addition, Nitya et al (2011) reported DPPH scavenging activities with methanolic extracts of Fusarium, Aspergillus, Penicillium and Mucor, with IC 50 values ranging between 200 and 325 lg/mL.…”

Genetic linkage between protein and DNA polymorphisms and antioxidant capacity of Cuminum cyminum L. accessions

“…Conversely, the natural antioxidants present in dietary plants can delay, inhibit, or prevent the oxidation of biomolecules, such as proteins and nucleic acids, and may scavenge free radicals or break the chain reaction due to their redox properties (Dua et al, 2012). An easy, rapid, and sensitive method used to screen antioxidants in plant extracts involves 1,1-diphenyl-2-picryl hydrazyl (DPPH) used in a free radical scavenging assay, and β-carotene-linoleate as an inhibitor of lipid peroxidation (Ravindran et al, 2012). The effects of dietary phenolic compounds are of interest due to their antioxidant effects, their ability to hinder oxidative degradation of lipids, and their ability to enhance the nutritional value of food (Srivastava et al, 2013).…”