Microbial Diversity in Bee Species and Bee Products: Pseudomonads Contribution to Bee Well-Being and the Biological Activity Exerted by Honey Bee Products: A Narrative Review

Abstract

Bees are important pollinators worldwide, promoting sustainability in agriculture and natural ecosystems. Moreover, honey bees produce a variety of honey bee products (beehive products). Honey is the main edible bee product. The consumption of pollen, bee bread, royal jelly, and propolis is becoming more popular nowadays. All these products are characterized by high nutritional value and/or bioactivity. A high microbial diversity has been reported in bees and beehive products, forming distinct microbial communities. The honey bee gut microbiome actively promotes good health and nutrient availability for the host. Furthermore, it prevents food spoilage and contributes to the maintenance of good hygiene conditions in the hive. Pseudomonads are often reported in investigations on bee and bee product microbiomes. Diverse Pseudomonas species demonstrate high metabolic adaptability, producing a wide range of bioactive enzymes and secondary metabolites. Several studies have provided evidence that Pseudomonads might play a role in bee well-being and the bioactivity exerted by honey bee products, though further research is warranted to fully understand the effects and mechanisms. The aim of this narrative review is to highlight the importance of Pseudomonads in the context of up-to-date knowledge regarding the bee and bee product microbiomes.

Enhancing Antioxidant and Antimicrobial Activities in Bee-Collected Pollen through Solid-State Fermentation: A Comparative Analysis of Bioactive Compounds

“…It is effective in producing lactic acid, which can help in preserving the BP and maintaining a stable pH during fermentation [ 25 ]. A. kunkeei is commonly found in bee products and is well adapted to the bee environment [ 60 ]. Its inclusion ensures a more natural and bee-friendly fermentation process because it is particularly adapted to the unique composition of bee-derived substrates, potentially making the fermentation process more efficient and tailored to the specific characteristics of the BP [ 61 ].…”

Shotgun Metagenomics Reveals Minor Micro“bee”omes Diversity Defining Differences between Larvae and Pupae Brood Combs

“…Another cluster includes potentially pathogenic bacteria-Pseudomonas [62,63] and Corynebacterium [64]-also found in small numbers in guts. However, it may include different members of Pseudomonas that differ in their ecology in the hive [65]. Its abundance correlates weakly with the other clusters.…”

Bee-Associated Beneficial Microbes—Importance for Bees and for Humans

“…Worker bees and queens share many essential gut bacterial species, and although not every species present in the forager is necessarily present in the queen, species such as Apb. kunkeei and Bombella apis (formerly Parasaccharibacter apium ) are common species in the queen’s gut [ 31 , 32 ]. The GIT in adult honeybees is divided into four parts: stomach (crop), middle throat, ileum, and rectum [ 22 ].…”

“…Depending on factors such as pollen and nectar sources, contact between bees, surrounding environment, pollination landscapes, and other variables already mentioned, there are significant variations between the main bacterial phylotypes dominant in bee microbiota, with many microbial species being endemic to the digestive tract of adult honeybees and other bee species, independent of the seasons and nutritional factors, with genera such as Lactobacillus (term used in the context of the significance from before changes to taxonomy in 2020 [ 25 ]) and Bifidobacterium appearing among the main microbial taxa, including in queen bees [ 8 , 18 , 32 , 37 ]. Indeed, bees and LAB have evolved in correlation with each other, and different genera of LAB are housed in the GIT compartments of bees, in their by-products, and in their hives [ 33 , 38 ].…”