Analysis of Purple Cleome (Cleome rutidospermae) Metabolites as Potential Organic Pesticides
Ali Ikhwan, Dian Indratmi, Hanim Inayatur Robbiya dan Annisa Noviyanti
Universitas Muhammadiyah Malang
Abstract
INTRODUCTION Purple Cleome (Cleome rutidosperme) is known to have metabolites that can be used as organic pesticides. This plant contains a group of alkaloid and flavonoid compounds which could be used as organic pesticides (Bose, et al., 2007). However, the types and concentrations of these compounds have not been studied in depth. This research is intended to examine further the types and concentrations of alkaloid and flavonoid which act as pesticides, especially organic fungicides on fungal pathogens Colletotrichum sp and their mechanisms in inhibiting these pathogens that attack chili plants. To achieve this goal, the research stages are as follows: (1) extraction of purple Cleome leaves with absolute methanol 1: 1 w / v; (2) metabolite analysis using GC-MS (Gass Chromatography – Mass Spectrophotometry) type QP2010S Shimadzu, with the RXi-5MS semi-polar columns, helium carrier gas with a flow rate of 0.5 ml / min, and a pressure of 27.4 kPa. The initial temperature of the GC oven was 120 oC with incremental increase of 5 oC/ min until it reached 320 oC and 1-2 ul (Hussain, and Maqbool, 2014) was sampled; and (3) pathogenic inhibition test with fungi. Colletotrichum sp. pathogen model. The data obtained were analyzed with the NCBI (National Center for Biotechnology Information) database to obtain specific metabolites that act as organic pesticides. RESULT AND DISCUSSION The GC-MS analysis of Purple Cleome leaf extracts analysed 18 metabolites and 3 of them were identified as organic fungicides as shown in the following table: Table 1: Analysis of Purple Cleome metabolites acting as organic fungicides No. Compound Name (CAS) Composition (%) Function 1. Propanoic acid C11H14O2 4,12 % • Acts as an antifungal and antibacterial agent by inhibiting their growth (Bose, et al., 2007). 2. Phenol C17H28O 8,38 % • Acts as an anti-microbial that is toxic and corrosive to microbes. Phenol can damage the hydrophobic components of cell membranes such as proteins and phospholipids. • Acts as an inhibitor for essential enzymes and as an active antimicrobial agent of vegetative cells of bacteria, viruses, and fungi. Phenol can reduce permeability of cytoplamide membrane and dead fungal cells (Rahman, et al, 2012) 3. Isopropyl myristate C17H3402 15,86 % • Act as an active ingredient of pesticides Besette and Brentwood (2007) The result of GC-MS analysis identified three metabolite compounds namely propanoic acid, phenol, and isopropyl myristate, with a total composition of 28.36%, which acts as an antifungal and antibacterial agent (Bose, et al. 2007). The inhibition mechanism by Propanoic acid varies depending on the microorganism. Some microorganisms have an enzyme system that converts succinate into Propionyl-Coenzyme, and it can be converted into B-alanine or directly into CO2. The microbial inhibition mechanism works by competing with acetate in the acetokynase system, resulting in blockage of chemical reaction from
Keywords: Metabolites, Pesticides, Organic, and Pathogens
Topic: Environmentally Sustainable Agriculture