Antimicrobial Properties of Different Bee Propolis (Blog Post #2)

Now approaching the end of summer, I am very excited to share with you the results of my experiment. I tested 17 microorganisms, (8 Gram positive and 9 Gram negative) and was able to derive data from 10 of the organisms tested due to various problems that occurred.  E. faecalis and B. megaterium are Gram positive bacterias that did not show any signs of inhibition by the propolis samples. S. pneumoniae was the only Gram positive organism that displayed slight inhibition around propolis samples from Russia, Tayabas, Lativa and Australia.

P. vulgaris is a Gram negative bacteria that showed slight around propolis samples from Bico, Washington State, and California. P. aeriginosa (Gram negative)  also had slight inhibition around Australia, Lativa and Russia. S. typhimurium (Gram negative) had slight inhibition around the samples from Australia and California. E. aerogenes (Gram negative) had slight inhibition around the California sample. The D1 strain of S. marcesens (Gram negative) had inhibtion around the Bico sample. E. coli (Gram negative) showed no inhibition and S. flexneri (Gram negative) showed the most inhibition out of all the organisms tested. This bacteria was inhibited by samples from Tayabas, Lativa, California. Washington State, Bico, and Australia.

From the results obtained, it can be determined that the propolis is most effective against microorganisms that dwell in or infect the human body, which would explain why the propolis is known for its healing properties and used around the world for the treatment of various ailments.

Data could not be gathered for the following Gram positive bacterias: S. epidermidis, B. cereus, S. pyogenes, S. aureus, B. subitilis, and the following Gram Negative bacterias: the WCF and 933 strains of S. marcesens. Data for these organisms could not be gathered because the disks placed on the plates with the propolis samples somehow shifted positions, therefore I was unable to determine which disk belonged to which propolis sample. When attempting do another trial of the protocol, the bacteria used to inoculate the plates were contaminated and it was very difficult trying to remake new bacterial stocks because the samples were becoming contaminated as well.

Despite this issue, one major result still stood out to me throughout the whole experiment. Although I previously stated that I could not gather data for S. pyogenes, the plate did show amazing inhibition  of the bacteria for 2 of the propolis samples. However, the disks with the propolis samples shifted, therefore I could not tell where the two samples were from and the issues from remaking bacteria stock interrupted my search. But this particular result I found the most interesting because S. pyogenes is the cause of Strep Throat and in countries around the world, and even in my home, honey is ingested to ease the symptoms and somehow cure the infected throat after a few days. Therefore, I am extremely excited to continue this experiment to determine the results for the rest of the microorganisms to determine the efficacy of propolis against these bacteria.

From this experiment I have learned two very important facts of life.  The first is that nothing comes out the way that is planned. There are always going to be discrepancies and problems that arise with protocols and results. However, it is your job as the researcher to ask yourself why is this occurring and devise a solution to the problem. The second thing that I learned is that one must be able to connect two points in order to have that wonderful “lightbulb” moment where everything finally comes together and makes sense. This is how I felt after looking at the S. pyogenes plate and is one of the many things about my research that makes me very excited. I look forward to continuing my researching and being a part of Dr. Mojica’s team.


Antimicrobial Properties of Different Bee Propolis (Blog Post #1)

My name is Nadina Horril and I am a Biology major here at Pace. This spring I began my research under my mentor, Dr. Mojica, researching and testing various bee propolis samples against different microorganisms. The purpose of my study is to determine the effectiveness of the bee propolis at inhibiting bacterial growth of both Gram negative and Gram positive organisms. I inoculated various bacterial samples as well as prepared my own version of antibacterial disks composed of the bee propolis extract. The objective of this experiment is to analyze and determine alternative antibacterial agents since antibacterial resistance is at its peak due to the widespread, unrestricted use of antibiotics.

The propolis, a natural resinous substance collected by honeybees from buds and exudates of plants, is believed to be use in the beehive as a protective barrier against enemies. The propolis is widely used as a popular remedy in folk medicine and as a constituent of biocosmetics. Recently, it is extensively used in food and beverages to improve health and prevent diseases. Depending on the season, bee species, vegetation and the area of collection, the chemical composition of propolis are qualitatively and quantitatively variable, resulting in diverse biological properties as well. Previously, the antimicrobial activity of several propolis samples obtained from various parts of the world (Europe, Australia, USA and the Philippines) were analyzed using 2 Gram positive organisms and 2 Gram negative organisms. The propolis samples were extracted with ethanol and the extracts were assayed with each microorganism. The results exhibit antimicrobial activity of several samples against some specific microorganism. The summer protocol will be an extension on this research to determine the effectiveness of the bee propolis against a wider range of microorganisms.

From this research, I hope to identify an alternative antibacterial agent, as well as educate others on the poor usage of antibacterial products and their disposal. The identification of an alternative agent could be novel to various scientific fields, as well as be a breakthrough in the eradication of various bacterial diseases that plague various countries around the world. Additionally, this project will give me the opportunity to gain a hands on experience to heighten my efficacy in the lab. Moveover, I am honored to continue my work with Dr. Mojica and be mentored by a well respected and highly accomplished professor.