Wattana  Panphut, 
    Anti Plant Pathogen of Bioactive Metabolite from <i>Piper retrofractum</i> Vahl,
    Journal of Engineering and Applied Sciences,
    Volume 12,Issue 23,
    2017,
    Pages 7321-7324,
    ISSN 1816-949x,
    jeasci.2017.7321.7324,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2017.7321.7324)
    Abstract: Plant pathology anthracnose by <i>C. acutatum</i> and <i>C. gloeosporioides</i> and root rot and vascular wilt
by <i>F. oxysporum</i> and <i>F. moniliforme</i> caused a serious problem of crop loss in Thailand. Agricultural chemicals
such as fungicides were sprayed on crops to control diseases that damaged field crops. This has created more
problems because fungicide residues have been found on food for human consumption, mostly from
post-harvest treatments. <i>Piper retrofractum</i> Vahl (long pepper) is in the Piperaceae family which can be found
in Kanchanaburi, Ratchaburi and Chanthaburi Provinces of Thailand. It has been used as a Thai traditional herb
ingredient in various treatment formulas. The aim of this research is to extract metabolite from long pepper using
several solvents and to perform therapeutic efficacy testing against fungal of plants pathogen disease. The
results showed that the bioactive metabolites extracted from <i>P. retrofractum</i> are effective against plant
disease-causing fungi <i>Fusarium moniliforme</i> DOAC 1224 causes the stalk rod disease, <i>F. oxysporum</i> DOAC
2269 causes the yellow wilt disease, <i>Colletotrichum gloeosporioides</i> DOAC 2213 and <i>C. acutatum</i> DOAC 2285
both cause the most destructive fungal disease, anthracnose. Total of crude extracted found in isopropanol is
2.193&plusmn;0.579 g/100 g of fresh pepper. Agar disc diffusion assay performed crude extracted concentrations
713 mg/mL against <i>C. gloeosporioides</i> is clear zone 5.25&plusmn;0.35 mm. Against <i>C. acutatum</i> is clear zone
11.00&plusmn;4.24 mm, against <i>F. moniliforme</i> is clear zone 9.00&plusmn;4.24 mm and against <i>F. oxysporum</i> is clear zone at
6.50&plusmn;0.71 mm. Moreover, the results can be concluded that isopropanol is an effective solvent for extracting
bioactive compounds from fresh <i>P. retrofractum</i>. The crude metabolites have shown potential for broad range
antifungal activities in plant pathogens.
    Keywords: Antifungul;bioactive metabolite;extraction;Piper retrofractum;plant pathogenic fungi;potential