Saccharomyces cerevisiae is a yeast that is commonly used in baking and various industries because of its usefulness. It can be easily grown at a low cost. Nowadays, there is a focus on finding safe and effective carriers.
Saccharomyces cerevisiae, with its round shape and protective membrane and cell wall, can be used to enclose and protect active substances, like a shield, preventing their degradation or creating a system that releases drugs slowly over time. The goal is to create the optimal conditions to achieve the best physical properties of Saccharomyces cerevisiae as a carrier.
Let’s look deeper into the recent research that shows the most suitable growth condition of these yeast cells.
Understanding Saccharomyces Cerevisiae
The name Saccharomyces cerevisiae has two parts with interesting meanings. The first part, “Saccharo,” refers to “sugar fungus” in Latinized Greek, while the second part, “cerevisiae,” means “of beer.” S. cerevisiae is a valuable yeast used in baking and various industries.
It is also commonly used as a model organism in biological studies because it can be easily cultured. The yeast cells can exist in two forms: haploid and diploid. Haploid cells have a simple life cycle through mitosis, but they can die under stressful conditions. Diploid cells also undergo mitosis, but when faced with high stress, they enter the meiosis life cycle and produce four haploid spores.
Yeast cells have strong structures that allow them to carry different active materials. Many experiments have been conducted to improve the number and size of yeast cells for use as carriers. Growth curves, such as the logistic growth equation, have been used to model their growth efficiently.
Culture Of Yeast Cells
A bioreactor was used to cultivate the yeast cells, providing them with the best conditions to grow. The bioreactor consisted of three main parts: a controller, a gas mixer, and a gas analyzer. To start, a synthetic culture medium of 2 liters was filled into the bioreactor vessel. Then, a suspension of yeast cells (108 cfu/ml) in a physiological serum was added to the vessel, about 3 ml in volume. The temperature was set at 30 °C, and the culture medium was stirred at a speed of 200 rpm. The bioreactor had a double jacket vessel, with circulating water between the two jackets, helping to maintain the desired temperature of the culture medium.
Yeast Cell Growth
The growth of yeast cells under different conditions was measured by counting the number of colonies on the fourth diluted plate using a colony counter. To perform the counting, 1 milliliter of the culture medium was diluted about 10^-1 four times using the physiological serum.
These dilutions were then spread onto four separate 2.0 ml Deep well plates for Hamilton. Additionally, samples of the culture medium were taken at different time points (0 to 13 hours), and their UV/Visible absorption at 600 nm was measured using a CECIL 9000 spectrophotometer.
This data was used to create a growth curve, which shows the typical phases of microbial growth: lag, log, stationary, and decline phases. The growth patterns and rates of the yeast cells were further analyzed using mathematical software called Matlab.
Determination Of Yeast Cell Size
During the logarithmic growth phase, the size of the yeast cell was observed and measured every hour for a period of up to 10 hours using light microscopy. By calculating the average size, the mean size of the yeast cell was determined. It is important for the yeast cell to have an appropriate size if it is being utilized as a carrier to load active materials.
Intricacies Of Yeast Cell Growth
The growth curves of yeast cells were examined under nine different conditions, varying the pH levels and percentage of dissolved oxygen (DO). Using the Matlab mathematical software, an equation was developed to describe the growth pattern of the yeast cells based on colony counting (CFU/ml × 108) on the Y-axis against time (h) on the X-axis.
Specifically, the growth curve under the condition of pH=4 and DO 5% was considered the best condition. This growth curve was fitted using the Richard equation to estimate the maximum growth rate. The Y-axis represented the maximum growth rate, while the X-axis represented the time in hours.
Result & Discussion
Currently, there is a focus on developing safe and effective carriers, particularly those that are natural and cost-effective. An ideal carrier should have the ability to load active ingredients efficiently and possess structural characteristics that enable the controlled release of those ingredients.
Saccharomyces cerevisiae yeast cells possess all these desirable qualities as carriers. To optimize the growth of yeast cells, two important parameters, pH and percentage of dissolved oxygen (DO), were carefully adjusted.
Through the study of various mathematical equations and software, it was demonstrated that a pH of 4 and a DO of 5% created the optimal conditions for yeast cells to reproduce and grow. This optimized condition not only enhanced the reproduction, growth, and overall size of the yeast cells but also made them highly suitable as carriers for active ingredients.
The findings revealed that yeast cells exhibited improved reproduction rates under lower pH levels and percentages of dissolved oxygen (DO). Among the three different DO levels tested, a decrease in acidity resulted in a shorter growth cycle. The enhanced growth observed under higher acidity conditions could potentially be attributed to the production of ethanol as a metabolite by the yeast cells.
Final Verdict
All in all, the result shows the optimal growth condition for Saccharomyces cerevisiae in terms of achieving the best morphological properties was found to be pH 4 and DO 5%. These findings highlight the yeast’s potential as an effective and cost-efficient carrier. It is recommended that future studies focus on encapsulating various active ingredients within these yeast cells as carriers and investigate their effectiveness and stability.
If you’re also conducting microbiology research and are in need of reliable lab equipment, MBP Inc. provides a wide range of solutions to meet your microbiological lab requirements. Our offerings include deep well storage plates to filtered tips, ensuring you have all the necessary essentials for your laboratory work.
