Green and black teas extracts are known for their antibacterial activity against many pathogenic microorganisms. These studies have been necessitated by the need to combat the recent rise of drugresistant human pathogens which is becoming a common occurrence in the world making easily manageable infections to become life threatening illnesses. This study evaluated the antimicrobial activity of water soluble green and black tea extracts from a high quality Kenyan tea clone TRFK 6/8 against antibiotic resistant Escherichia coli ATCC 25922 and Staphylococcus aureusATCC 25923 using agar well diffusion method. Green and black tea extracts effectively inhibited the growth of both E. coli ATCC 25922 and S. aureus ATCC 25923 at concentrations of 0.1 and 0.05 mg/ml, respectively after 24 h. Green tea extracts and gentamicin showed greater zone of inhibition compared to penicillin G. In addition, the possible synergistic activity of water soluble green tea extract and antibiotics was also determined using agar well diffusion method. A combination of penicillin G and green tea extract inhibited the growth of E. coli ATCC 25922 and S. aureus ATCC 25923 compared to penicillin G alone while gentamicin exhibited an additive and antagonistic effect depending on tested bacteria. Green and black tea extracts can be used as an antimicrobial agent and also green tea extract can be used in combination with penicillin G to manage resistant pathogenic bacteria. Furthermore, tea which is a proven safe, cheap and readily available compound can be used in more ambitious trials to test the antimicrobial efficacy and chemo-preventive effects in animal and human models.

No abstract

Occlusion of the stem vasculature by microorganisms that proliferate in the vase water, or the plant vessels, leads to water stress symptoms that reduce postharvest quality of cut flowers. This study aimed to determine the effects of pulsing and wet-cold storage on the microbial profiles in cut Gladiolus grandiflorus L. cv. Fado. Pulsing treatments of 600-ppm 8-hydroxyquinoline sulfate plus 5% sucrose solution versus distilled water were administered before wet cold storage periods of 0-5 days in cut Gladiolus, previously grown from corms under open field. A two-by-six factorial experiment embedded in a completely randomized design with four replicates was accomplished. Proc GLM in two-way Anova was adopted, and the means were separated using Tukey’s test at a 5% level of significance. The pulsing treatment of 600 ppm 8-HQS plus 5% sucrose, the wet cold storage duration and their interactive effects significantly (P˂0.0209; ˂0.0001 and ˂0.0001 respectively) affected the means of the colony-forming units in the vase water of cut Gladiolus at senescence. The prolonged vase life of cut gladioli spikes was associated with decreased microbial proliferation as influenced by pulsing and wet storage duration of up to 4 days. Data generated from this study will improve existing technologies related to the quality and market value of this Gladiolus cultivar.

2016-12-23T18:52:10