Characterisation of bacteria isolated from the stingless bee,Heterotrigona itama, honey, bee bread and propolis

Abstract

Bacteria are present in stingless bee nest products. However, detailed information on their characteristics is scarce. Thus, this study aims to investigate the characteristics of bacterial species isolated from Malaysian stingless bee, Heterotrigona itama, nest products. Honey, bee bread and propolis were collected aseptically from four geographical localities of Malaysia. Total plate count (TPC), bacterial identification, phenotypic profile and enzymatic and antibacterial activities were studied. The results indicated that the number of TPC varies from one location to another. A total of 41 different bacterial isolates from the phyla Firmicutes, Proteobacteria and Actinobacteria were identified. Bacillus species were the major bacteria found. Therein, Bacillus cereus was the most frequently isolated species followed by Bacillus aryabhattai, Bacillus oleronius, Bacillus stratosphericus, Bacillus altitudinis, Bacillus amyloliquefaciens, Bacillus nealsonii, Bacillus toyonensis, Bacillus subtilis, Bacillus safensis, Bacillus pseudomycoides, Enterobacter asburiae, Enterobacter cloacae, Pantoea dispersa and Streptomyces kunmingensis. Phenotypic profile of 15 bacterial isolates using GEN III MicroPlate™ system revealed most of the isolates as capable to utilise carbohydrates as well as amino acids and carboxylic acids and derivatives. Proteolytic, lipolytic and cellulolytic activities as determined by enzymatic assays were detected in Bacillus stratosphericus PD6, Bacillus amyloliquefaciens PD9, Bacillus subtilis BD3 and Bacillus safensis BD9. Bacillus amyloliquefaciens PD9 showed broad-spectrum of antimicrobial activity against Gram-positive and Gram-negative bacteria in vitro. The multienzymes and antimicrobial activities exhibited by the bacterial isolates from H. itama nest products could provide potential sources of enzymes and antimicrobial compounds for biotechnological applications.

Probiotic Properties of Bacillus Strains Isolated from Stingless Bee (Heterotrigona itama) Honey Collected across Malaysia

“…The amount of aerobic bacteria detected in the fresh honey of stingless bees could be considered relatively low, with a mean value of 1.7 x 10 2 CFU/g, compared to its other byproducts, such as beebread and propolis (1.83 × 10 6 CFU/g) [12,37]. This is supported by the results from a previous study, as the presence of aerobic bacteria in honey was also detected in the range of 5.7 × 10 0 to 52.8 × 10 4 CFU/g [38].…”

“…A recent study found that the highest microbial diversity was found in multifloral honey [13]. Recently, the presence of B. altitudinis in stingless bee honey, H. itama, was reported for the first time [12]. B. altitudinis had been previously found in Apis mellifera honey together with other Bacillus isolates, namely B. licheniformis, B. safensis, B. zhangzhouensis, and B. xiamenensis [13].…”

“…However, due to their spore-forming characteristics, which are highly stable in acidic pH, they can also colonize different environments, such as honey and various food matrices [11]. For example, Bacillus species such as B. subtilis, B. licheniformis, B. pumilus, and B. amyloliquefaciens have been detected in the fermentation of both stingless bee honey and Apis mellifera honey [12,13]. These bacteria have advantages over non-spore formers such as lactic acid bacteria (LAB) due to their heat-resistant spores [14].…”

Organoleptic, Physico-Chemical and Palynological Properties of Honey in the West Siberian Region of Russia

“…A number of researchers confirmed that they had found that in honey microbiota and honey bag of bee there were bacterial strains with the high level of antimicrobial activity against pathogens which were resistant to antibiotics. This reveals antimicrobial properties of honey [10][11].…”

Taxonomic note: speciation within the operational group Bacillus amyloliquefaciens based on comparative phylogenies of housekeeping genes

“…B. amyloliquefaciens strains are capable of producing different bioactive compounds useful in bio-control of plant and human pathogens (Balhara et al, 2011). This bacterial species is widely distributed in various niches including soil (Lončar et al, 2013), foods (Krawczyk et al, 2016), fruits (Wu et al, 2017), bee products (Ngalimat et al, 2019), animal faeces (Singh et al, 2013), and aquatic environments (Daas et al, 2018).…”