Screening the efficacy of extracts of different spices in inhibiting the growth of foodborne bacterial isolates

S.K Munshi,A.O Abokor,S Paul,T Ishma,T Islam,T Akter,J Ahmmed,I.T Nur,S.R Shewly

doi:10.26656/fr.2017.6(1).289

Abstract

Owing to the presence of a diverse group of phytochemicals, spices could be potential sources of antibacterial and antioxidant agents. The present investigation was aimed to determine and compare the antimicrobial activities of different spices. A total of 5 spices including cardamom (Seeds, Elettaria cardamomum), cinnamon (Barks, Cinnamomum verum), clove (Flower buds, Syzygium aromaticum), Indian bay leaf or Tejpat (Dried leaves, Cinnamomum tamala), and cumin (Seeds, Cuminum cyminum) were collected. Different extracts (crude, aqueous, ethanolic, and methanolic) of spices were prepared and examined for antimicrobial activity against previously isolated foodborne bacterial isolates. Extracts from the tested spices showed significant inhibitory effects (mostly with >10 mm mean zone of inhibition) as revealed by the agar well diffusion technique. Clove among the tested spices was found to be the prominent one in eliminating foodborne pathogens. Methanolic extracts followed by ethanolic extracts were determined to be most effective against the bacterial isolates when the relative effectivity of different extracts was compared. The frequently encountered minimal inhibitory and bactericidal concentrations of the spices were 12 and 24 mg/mL, respectively. All the spice extracts showed considerable antimicrobial traits which validate their potential and applicability as natural food preservatives and decontaminants.

Highlights

Despite the food safety concern and recent technological advancements, foodborne diseases remain to be a big concern worldwide as well as in Bangladesh (Gottardi et al, 2016; Noor and Feroz, 2016)
All the spice samples showed their efficiency in reducing the growth of foodborne bacterial isolates and significant differences (P < 0.05) were observed in the mean zone of inhibition by different extracts (Table 1)
Mean±standard deviations (SD) zone of inhibition found for different extracts of Cardamoms was minimal with the highest measurement of 12.7±1.53 mm and no effect was found against Vibrio cholerae (Table 1)

Summary

Introduction

Despite the food safety concern and recent technological advancements, foodborne diseases remain to be a big concern worldwide as well as in Bangladesh (Gottardi et al, 2016; Noor and Feroz, 2016). To ensure food safety and quality, controlling the growth of spoiling and pathogenic foodborne microorganisms is crucial. Suppression of one or more essential factors associated with microbial survival could ensure food conservation (de Souza et al, 2005). Synthetic preservatives that have been used in foods for decades could be toxic to humans and may have adverse health consequences (de Souza et al, 2005; Chakraborty et al, 2020). The concern for replacing synthetic preservatives with renewable, effective, and non-toxic compounds is raising (de Souza et al, 2005; Purkait et al, 2018). Plant products with antimicrobial properties attract special focus for potential use in food processing to control bacterial and fungal growth (Jahan et al, 2018; Hossaini et al, 2020; Hossaini et al, 2021). Plant-derived antimicrobial compounds have been used for food preservation for centuries (Dhiman et al, 2016)

Methods

Results

Conclusion