Int. J. Pharm. Sci. Rev. Res., 26(1), May – Jun 2014; Article No. 51, Pages: 301-308 ISSN 0976 – 044X International Journal of Pharmaceutical Sciences Review and Research Available online at www.globalresearchonline.net © Copyright protected. Unaut horised republicat ion, reproduction, distribution, dissemination and copying of this document in whole or in part is strictly prohibited. 301 Faten K. Abd El-Hady 1* , Mohamed S. Abdel-Aziz 2 , Kamel H. Shaker 3 , Zeinab A. El-Shahid 1 , Mohamed A.Ghani 4 1 Chemistry of Natural Products Department, National Research Center, Egypt. 2 Department of Microbial Chemistry, National Research Center, Egypt. 3 Chemistry of Natural Compounds Department, National Research Center, Egypt. 4 Red Sea Marine parks, Hurghada-Red Sea – Egypt. * Corresponding author’s E-mail: fatenkamal@hotmail.com Accepted on: 01-04-2014; Finalized on: 30-04-2014. ABSTRACT Acetylcholinesterase (AChE) inhibitors have received considerable attention as alternatives in treatment of Alzheimer's disease (AD). The damage caused by reactive oxygen species is considered a contributing factor to AD. Three fungi (FC1, FC2 and FC3) were isolated from the soft corals; S inularia sp. and Lobophyton sp. The antioxidant activities (DPPH and Xanthine Oxidase assays), (AChE) inhibitory activity and antimicrobial activity for twelve different fungal extracts were evaluated. Mycelial ethylacetate extract from the static culture of the fungus FC2 (Emericella unguis 8429) had the highest free radical scavenging activity against DPPH and superoxide anion radicals. Mycelial extract from the shake culture of the isolated three fungi have mild scavenging activity, while their supernatant extracts had no free radical scavenging activity. These data are mentioned for the first time. Screening the AChE inhibitory activity: only FC2 had a significant activity for mycelial extract of the static culture, while mild activity was found in the supernatant extract of the same culture. The three fungal extracts in shake conditions had no AChE inhibitory activity. The supernatant and mycelial extracts from the static culture of the fungus FC2 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans . The supernatant extract from the static culture of FC3 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans. It could be concluded that, the isolated marine fungus Emericella unguis showed different biological activities as AChE inhibitor (reported for the first time), antioxidant, antimicrobial rather than the unidentified other two fungi (FC1, FC3). Keywords: Marine fungi, Corals, Acetylcholinesterase inhibitors, antioxidant, antimicrobial activities. INTRODUCTION ChE inhibitors have received considerable attention as alternatives in treatment of Alzheimer's disease (AD). Alzheimer's disease is the most common, complex and challenging form of neuro-degenerative disease associated with dementia in the elderly. Acetylcholine is a neurotransmitter inhibited by acetylcholinesterase (AChE), considered to play a role in the pathology of AD. 1 Despite the unknown etiology of AD, elevation of acetylcholine amount through AChE enzyme inhibition has been accepted as the most effective treatment strategy against AD. However, the present drugs (tacrine, rivastigmine and donezepil) with AChE inhibitory activity possess some side effects. 2 Therefore, natural AChE inhibitors have become the remarkable alternatives in treatment of AD. Microbes are vast and largely untapped resources of novel, structurally diverse metabolites. Many of these metabolites possess highly valuable bioactivities to humans. Marine-derived microbes, fungi in particular have long been recognized as potential source of structurally novel and biologically potent metabolites. 3,4 Because of their particular living conditions, salinity, nutrition, high pressure, temperature variations, competition with bacteria, viruses and other fungi, they may have developed specific secondary metabolic pathways compared with terrestrial fungi. 5 Previous literature shows that marine-derived fungi have been recognized as one of the tapped sources for new biologically active secondary metabolites including antitumor, antibacterial, antiviral, antifungal, anti- inflammatory and anticancer activities and enzyme inhibitor compounds. 6 To this day, there are no reports that marine compounds isolated from microorganisms of the Red Sea area of Egypt have been used for the treatment of Alzheimer's disease. Hence, we tried to study soft coral associated fungi and some of their biological activities. The present investigation is an outcome of such a study on the fungus Emericella unguis associated with a soft coral S inulariasp. and screen for acetylcholineseterase inhibition activities. MATERIALSAND METHODS Soft coral materials Soft coral samples; S inularia sp. (from which fungi FC1 and FC2 were isolated) and Lobophyton sp. (from which fungus FC3 was isolated) were collected from Hurghada coast, Red Sea, Egypt. The site is Shaa’b Al areq latitude, N 27°25 ˊ 08.9˝, E 33° 51ˊ 0.5˝ the samples were collected at depth of 5m - 8m in January2013 and kept frozen until the work-up. The morphological taxonomy of the soft corals was identified by Mohamed A. Ghani – environmental researcher -Red Sea Marine parks, Hurghada, Red Sea, Egypt. Coral-Derived Fungi Inhibit Acetylcholinesterase, Superoxide Anion Radical, and Microbial Activities A Research Article