International Journal of Research Publication and Reviews, Vol 4, no 10, pp 1505-1509 October 2023 International Journal of Research Publication and Reviews Journal homepage: www.ijrpr.com ISSN 2582-7421 Oregano (Origanum Vulgare) and Lemongrass (Cymbopogon Citratus) Crude Extracts with Virgin Coconut (Cocos Nucifera) Oil: Pesticide for American Cockroaches (Periplaneta Americana) Marylle C. Nuay a , Ian M. Buenavista a , Angelo Dominic S. Delos Santos a , *Aldrian Dheen M. Magnaye b a Grade 10 STEM-A 2022-2023, Don Pablo Lorenzo Memorial High School – Junior High School, Sta. Maria, Zamboanga City, Philippines. b Teacher I – Research III and IV, Don Pablo Lorenzo Memorial High School – Junior High School, Sta. Maria, Zamboanga City, Philippines. aldrian.magnaye@deped.gov.ph DOI: https://doi.org/10.55248/gengpi.4.1023.102641 A B S T R A C T This study was conducted to determine the potential of Oregano (Origanum vulgare) and Lemongrass (Cymbopogon citratus) crude extracts with Virgin Coconut (Cocos nucifera) Oil as pesticide for American (Periplaneta americana) cockroaches. This study used the Completely Randomized Design. This study had four treatments: one (1) control and three (3) experimental. There are four (4) replicates for each treatment and three (3) samples for each replicate amounting to 12 samples per treatment. Treatments were applied directly to the cockroaches by spraying 5 times. After 12 hours of being sprayed by treatments, the dependent variable – mean number of cockroaches died, was measured. Based on the results, treatments 1, 3, and 4 have a mean of 3.00 with a standard deviation of 0.00, while treatment 2 has a mean of 2.75 with a standard deviation of 0.50. It was found out that there is no significant difference among the treatments in terms of the mean number of cockroaches died. Therefore, Oregano (Origanum vulgare) and Lemongrass (Cymbopogon citratus) crude extracts with Virgin Coconut (Cocos nucifera) Oil has the potential to be pesticide for cockroaches after 12 hours of being sprayed. Keywords: Crude Extracts, Pesticide, Completely Randomized Design, Oregano (Origanum vulgare), Lemongrass (Cymbopogon citratus), Virgin Coconut (Cocos nucifera) Oil, American (Periplaneta americana) cockroaches 1. Introduction Cockroaches are insects that serve as disease vectors and sources of bacterial infections found in homes. It spread at least 33 kinds of bacteria, 6 kinds of parasitic worms, and 7 other kinds of human pathogens (Drive-Bye Exterminators, 2018) that are very dangerous to humans. It can spread diseases such as gastroenteritis, dysentery, cholera, and typhoid fever (Garfield Pest Control, 2021). In the Philippines, American cockroaches are commonly found inside and outside homes (Rentokil, 2023). Pesticides are used to kill and protect people from cockroaches. Pesticides are loaded with toxic chemicals, including DDT (Coppock, 2011), which is poisonous and very dangerous to human health. Recently, there have been many reports of allergic and toxic effects from using pesticides. In addition, it causes vomiting, tremors or shakiness, seizures, and diseases in humans (Kabasenche & Skinner, 2014). Lemongrass (Cymbopogon citratus) and Oregano (Origanum vulgare) are indigenous plants that have been used commonly in the Philippines for their medicinal uses. Oregano is a rich source of vitamin C that helps reduce cough. It also helps fight against some bacteria and viruses to the human health. Lemongrass helps prevent the growth of some bacteria that also helps reduce fever. It provides certain vitamins such as Vitamin A and C that treat stomach-aches, high blood pressure, etc. (RxList, n.d.). These two indigenous plants contain active ingredients and compounds that have the potential to be pesticide. This study aimed to determine the activity of Oregano (Origanum vulgare) and Lemongrass (Cymbopogon citratus) crude extracts with Virgin Coconut (Cocos nucifera) Oil on American (Periplaneta americana) cockroaches. Furthermore, this study sought to determine the following: mean±SD number of cockroaches died in each of the 4 treatments [Treatment 1 - Commercial pesticide (control); Treatment 2 - 0.6 Oregano Crude Extract (OG) / 5mL Virgin Coconut Oil (CO) + 0.6g Lemongrass Crude Extract (LG) / 5mL Virgin Coconut Oil (CO); Treatment 3 - 0.4g OG / 5mL CO + 0.8g LG / 5mL CO; and Treatment 4 - 0.8g OG / 5mL CO + 0.4g LG / 5mL CO] after 12 hours; and significant difference among the 4 treatments in terms of mean±SD number of cockroaches died. The significance of this study is that it will help family members ensure that it is much safer than chemical pesticides. It can help lessen the number of reports due to the toxic effects of pesticides on humans. This study is only delimited to determine pesticidal activity of oregano and lemongrass crude extract with virgin coconut oil on cockroaches to the four treatments and the mortality of the cockroaches. The researchers acquired the cockroaches wherein characteristics such as the age and sex of the cockroaches are not considered in this study.