Abstract:

This dataset contains both time lapse and high speed micrographs of a bacterial suspension flowing past stationary crude oil droplets in a microfluidic channel collected between February 2, 2017 and June 20, 2017 in a laboratory at Texas A&M University-Corpus Christi. Time lapse images are recorded at intervals between 30 sec and 5 min with an Andor EMCCD camera and high speed images are recorded at 1000 fps for 1 sec periods at intervals of 10 min with an IDT high speed camera. All images are acquired with a Nikon Ti-E microscope using DIC or phase contrast microscopy. Additionally processed images for PIV-assisted PTV measurements along with flow measurement data and particle position and velocity data are included. This dataset shows bacteria forming aggregates and streamers on the surface of an oil droplet and analyzes high speed imaging data for determining the hydrodynamic impact of said aggregates.

Suggested Citation:

White, Andrew, Maryam Jalali and Jian Sheng. 2018. Micrographs and flow measurements of bacterial aggregates on an oil droplet in a microchannel. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7N58JTF

Publications:

White, A. R., Jalali, M., Boufadel, M. C., & Sheng, J. (2020). Bacteria forming drag-increasing streamers on a drop implicates complementary fates of rising deep-sea oil droplets. Scientific Reports, 10(1). doi:10.1038/s41598-020-61214-9

White, A. R., Jalali, M., & Sheng, J. (2020). Hydrodynamics of a Rising Oil Droplet With Bacterial Extracellular Polymeric Substance (EPS) Streamers Using a Microfluidic Microcosm. Frontiers in Marine Science, 7. doi:10.3389/fmars.2020.00294

Purpose:

These data were collected to investigate how bacteria form aggregates on rising crude oil droplets and what implications these aggregates would have.

Data Parameters and Units:

This dataset contains data from 8 experiments separated into folders by date. 2_2_2017_experiment: drop phase: crude oil (Macondo Surrogate oil) with 0.1% v/v Corexit 9500A, drop diameter: 250 micron (with satellite droplets), continuous phase: Difco marine nutrient broth (8 g/L), suspended phase: Pseudomonas P62 and flow speed: 9 mm/s. Folder includes a composite 20X differential interference contrast (DIC) micrograph taken 120 hours after introducing bacteria. 4_10_2017_experiment: drop phase: crude oil (Macondo Surrogate oil), drop diameter: 170 micron, continuous phase: Difco marine nutrient broth (8 g/L), suspended phase: Pseudomonas P62, flow speed: 3 mm/s. Folder includes a series of 20X DIC micrographs showing a time lapse of aggregation on a crude oil droplet over two days. Time between images is 30 s. 4_23_2017_experiment: drop phase: crude oil (Macondo Surrogate oil), drop diameter: 240 micron, continuous phase: Difco marine nutrient broth (8 g/L), suspended phase: Pseudomonas P62, flow speed: 2.3 mm/s. Folder contains 9 subfolders with high speed imagining data. The times on each subfolder indicate the elapsed time since first exposure of bacteria to the droplet at which the high-speed data applies. More details in read me file. 5_5_2017_experiment: drop phase: crude oil (Macondo Surrogate oil), drop diameter: 170 micron, continuous phase: DI Water with trace surfactants from 1 micron latex sphere stock, suspended phase: 1 mircon latex spheres with light unknown contamination, flow speed: 2.2 mm/s. Folder includes a time lapse 20X DIC micrographs showing the aggregation of 1 micron latex spheres due to microbial contamination. The interval between images is 5 min. 5_11_2017_experiment: drop phase: crude oil (Macondo Surrogate oil), drop diameter: 170 micron, continuous phase: DI Water with trace surfactants from 1 micron latex sphere stock, suspended phase: sterile 1 micron latex spheres, flow speed: 2.5 mm/s. Folder includes a 20X DIC micrograph. 5_30_2017_experiment: crude oil (Macondo Surrogate oil), drop diameter: 175 micron, continuous phase: Difco marine nutrient broth (8 g/L), suspended phase: Pseudomonas P62, flow speed: 3.6 mm/s. Folder includes a time lapse 20X DIC micrographs separated into 5 subfolders in sequential order. Date and time of acquisition of each image is included in the image. Time between images is 30 s. A composite DIC micrograph also shows the extent of the aggregate tail after 50 min. 6_12_2017_experiment: crude oil (Macondo Surrogate oil), drop diameter: 122 micron, continuous phase: 10 mg/L non-attached EPS isolated from Sagittula stellata, suspended phase: 1 micron latex spheres, flow speed: 1.9 mm/s. Folder includes two time lapses contained in the following two subfolders with a time lapse 20X DIC micrographs demonstrating that 1 micron latex spheres do not aggregate on a crude oil droplet in a flow containing non-attached EPS isolated from Sagittula stellata and a time lapse 20X DIC micrographs demonstrating that non-attached EPS isolated from Sagittula stellata with 1 micron latex beads later found to be slightly contaminated with unknown bacteria does form aggregates on the crude oil drop surface. Additionally, a composite 40X phase contrast micrograph showing the extent of the streamer tail that forms. 6_20_2017_experiment: crude oil (Macondo Surrogate oil), drop diameter: 230 micron, continuous phase: 10 mg/L non-attached EPS isolated from Roseobacter, suspended phase: particles from EPS stock, flow speed: 2 mm/s. Folder includes a 20X phase contrast micrograph after 6.5 hr of experiment time and a time lapse of 20X phase contrast micrographs. Time between images in 30 s. Micrographs of bacterial aggregates and streamers forming on a crude oil drop; velocity (pixels/ms)

Individual Files: