ABSTRACT
The use of antibiotic growth promotants in poultry rearing is a public health concern due to antibiotic resistance in bacteria and the harborage of resistance genes. Lupulone, a hop ß-acid from Humulus lupulus, has been considered as a potential feed additive growth promotant. Here, the effect of lupulone was evaluated for its effect on the microbiota of the chicken intestine. The intestinal microbiota of broilers was quantified after the addition of 125 mg L(-1) lupulone to water and challenge with Clostridium perfringens. Microbial DNA was extracted from the broiler midgut and cecal sections and bacterial groups were quantified using real-time PCR. The predominant cecal bacterial groups were Clostridium leptum subgroup 16S rRNA gene Cluster IV, Clostridium coccoides subgroup 16S rRNA gene Clusters XIVa and XIVb and Bacteroides, whereas Lactobacillus, the Enterobacteriaceae family and Enterococcus dominated the midgut. Lupulone at 125 mg L(-1) significantly decreased the C. perfringens subgroup 16S rRNA gene Cluster I, which contains several pathogenic species, in both the midgut and the cecum and Lactobacillus in the midgut. No significant changes were noted in the overall microbiota for the cecum or the midgut. Lupulone warrants further evaluation as a botanical agent to mitigate C. perfringens overgrowth in antibiotic-free reared poultry.
Subject(s)
Bacteria/drug effects , Chickens/microbiology , Humulus/chemistry , Intestines/microbiology , Metagenome/drug effects , Terpenes/pharmacology , Animals , Anti-Bacterial Agents/pharmacology , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Clostridium perfringens/pathogenicity , Colony Count, Microbial , DNA, Bacterial/genetics , Polymerase Chain Reaction , RNA, Ribosomal, 16S/geneticsABSTRACT
The antimicrobial activity of hop resins against Streptococcus salivarius , Staphylococcus aureus (two strains), Bacillus megaterium , Escherichia coli B, and Bacillus subtilis was investigated. However, resistance development was carried out on Streptococcus salivarius , Staphylococcus aureus (two strains), and Bacillus megaterium . The two hop resins used were iso-alpha resin and beta resin. Prior to resistance development, S. salivarius , S. aureus , and B. megaterium were all inhibited by the iso-alpha-hop resin in the 0.01 to 0.03% range. The beta-hop resin which, according to the literature, is more active than the iso-alpha resin initially inhibited these organisms at the 0.003 to 0.01% concentrations. The ease of resistance development varied between the different microbes, B. megaterium being the least prone to develop resistance.
ABSTRACT
A number of edible plant species were investigated for antifungal agents. Whole sprouts and extracts of plant organs were tested in several assays, including bioautography. Amaranth, coffee ( Coffea arabica ), rice, coleus, violet, chervil, and lotus ( Nelumbo nucifera ) showed antifungal activity. Rhizomes of lotus had potent antifungal activity against Aspergillus niger , Trichoderma viride , and Penicillium spp. Further work is merited for characterization of this antifungal agent. Screening of sprouting plants and terrestrial aquatic plants may be a fruitful approach to finding new antimicrobials.
