Dennettia tripetala: Hot aqueous dried plant part and selected chemical components of the plant as biopreservative in the storage of Vigna unguiculata grains Temitope Omolayo Fasuan * , Chidubem Theresa Chukwu Department of Food Technology, Akanu Ibiam Federal Polytechnic, Unwana, Ebonyi State, Nigeria article info Article history: Received 15 July 2020 Received in revised form 11 August 2020 Accepted 23 August 2020 Available online xxx Keywords: Dennettia tripetala Vigna unguiculata grains Bioactive components Amino acids Postharvest biopreservative abstract The identification of bioactive components and biopreservative effect of Dennettia tripetala hot aqueous fruit extract were studied. The identified bioactive components of the aqueous extract included meth- aqualone (51.53%), [1,2-Benzenedicarboxylic acid, 4-methyl-5-(1-methylethyl)-, dimethyl ester] (10.46%), [2,1,3-Benzoselenadiazole, 4,6-dichloro-] (4.53%), [o-Xylene] (0.54%), and [Ethane, 1,1-bis(p-chlor- ophenyl)-] (0.57%). The extract was able to preserve Vigna unguiculata grains for thirty weeks without insect-pests infestation and significant degradation in nutritional, biological value and functional char- acteristics. The biopreservation effect of the extract could be attributed to the presence of [1,2- Benzenedicarboxylic acid,4-methyl-5-(1-methylethyl)-, dimethyl ester]; and [Ethane, 1,1-bis(p-chlor- ophenyl)]. The study showed the feasibility of hot aqueous extraction of bioactive compounds from D. tripetala and application as postharvest biopreservative for cowpea grains. Preservation of the grains could improve food security and enhance food safety in nations where cowpea are consumed, exported or imported. © 2020 Elsevier Ltd. All rights reserved. 1. Introduction Postharvest losses are one of the major factors against food security and sustainability in many nations of the world. Over 30% of the annual world food production is loss during postharvest handlings while about 30e70% of grains are loss annually (Segun et al., 2014; Sawicka, 2019). There is a need to reduce losses after harvest, especially in developing countries, which could be a sus- tainable solution to improve food availability, reduce hunger as well as improve the living conditions of farmers (Sawicka, 2019). During temporary storage (such as in homes, markets, exporting), grains are highly susceptible to insect-pest attacks due to inade- quate access to efficient storage or modern storage facilities such as silos. Most traders resulted in applying some toxic synthetic chemicals as a means to control insect-pest invasion. Cowpea (Vigna unguiculata) is a vital grain legume in Africa, parts of America and Asia. Cowpea had been identified as the cheapest source of dietary protein for low-income households. In Nigeria, over 4.5 million hectares are cultivated annually for cowpea and this represented over 60% of the world total production for cowpea (FAOSTAT, 2011). Cowpea had found many applications both domestically and industrially; and these include the produc- tion of beanball (akara), bean paste (moin-moin), complementary food, enriched breakfast cereals, baked products, among others. However, during the storage of cowpea, the main postharvest loss is through insect-pests (mainly weevils) attack. Thus, cowpea cannot be stored for a long time without the application of pesticides. The attacks of weevils on this crop had led to huge economic, nutri- tional, and market losses. Previous studies on the control of weevils in stored cowpea included the use of chopped garlic, chillies and peppermint (Tiroesele et al., 2015). Reuben et al. (2006) also researched the use of Tephrosia vogelii leaf powder and tobacco leaf powder. However, these plant materials have not been adequately controlled weevils in stored cowpea. Moreover, there is no infor- mation on the biochemical characterization of the botanicals used for the insect-pest control and the treated cowpea grains. Weevils are primarily attracted to stored grains. The infestation of weevils resulted in huge losses annually. The conventional methods of controlling insect-pests in grains during storage were through the use of synthetic chemicals. Chemical pesticide residue in agricultural produce has been of concern due to its direct adverse * Corresponding author. E-mail address: temitopeomolayo@yahoo.com (T.O. Fasuan). Contents lists available at ScienceDirect Journal of Stored Products Research journal homepage: www.elsevier.com/locate/jspr https://doi.org/10.1016/j.jspr.2020.101698 0022-474X/© 2020 Elsevier Ltd. All rights reserved. Journal of Stored Products Research 89 (2020) 101698