Science Buddies: "Ask an Expert"

Hello,

My partner and I are planning to complete a project on Moringa Oleifera, specifically its efficacy in treating diabetes. We were wondering, is there any way to formulate an experiment without using mice, because that is how the majority of research had been done.

Thanks,
Meenakshi Singhal

Hi Meenakshi,

There's probably not an easy way for you to do this. Instead of working in animals, labs often work with cells cultured in dishes. If you know which cells MO is supposed to affect, it might be possible for you to find a lab where you could culture these cells and treat with MO to study its effects directly on the cells. This would definitely require you to work with an established lab; however, since cell culture requires equipment you are not likely to find at your school.

A paper I just skimmed seems to suggest that MO might work in the gut to decrease glucose uptake, possibly because it is high in fiber, which slows the rate of food progression from the stomach to the small intestine. Perhaps you could do a study of the fiber content in different parts of the MO plant (multiples parts of the plant are edible, including the leaves, the seed pod or "drumstick", etc.) to determine which might be the most beneficial for a person with diabetes.

I'm sure there are many other options to consider as well. Any other experts want to chime in?
JMP

Hello,

Thanks for the clarification. I've decided to instead focus on the water purification abilities of Moringa.
I want to build off of the idea of Moringa and f-sand, as described in the following links:

http://psumoringa.org/results.html
http://www.personal.psu.edu/lrm185/blog ... edSand.pdf

I was thinking about building a filter utilizing the f-sand that could be easily built by people in Third World countries, and I managed to contact the director of the research project. However, I'm not sure what a good, testable question would be.

Thanks,
Meenakshi

Hi Meenakshi,

This sounds like a really interesting project for you to work on. Obviously you'll want to test a question that you find interesting and relevant. One way to structure a question would be to compare the ability of the f-sand (i.e. with the Moringa attached) vs. sand without the Moringa (or some other water filtration system) on the ability to purify water of something specific. For example, you could test what is most effective at ridding water of E. coli: f-sand, sand without Moringa, or a normal water filter.

This is just one possibility. Can you think of anything else?

Hope this helps,
JMP

Hello JMP,

I was thinking about testing the most effective amount of MO protein per volume of sand needed to filter the water, or maybe how many times the sand can be utilized before it doesn't have any effect anymore. I have months to complete the project, so I don't think it would be possible to construct an entire filter that doesn't have any problems and can actually be used in third world countries.

I was wondering: the sand used to make f-sand in the experiment is anionic. Is sand naturally anionic?

Thanks,
Meenakshi

Hi Meenakshi,

I have been following your posts with JMP and this sounds like a really neat and potentially useful project. I read the first 8 pages of the thesis from the link you sent so i could understand the procedure and i did see mention of the sand being anionic--that is, negatively charged. From what little i know of soil chemistry, i thought it was CLAY that had the negative charges that can hold cations like calcium and magnesium in the soil: https://www.extension.purdue.edu/extmed ... Y-238.html

I did not see any statement of where the 'sand' came from in the thesis. In the Methods section it said that the f-sand was prepared using 'clean sand' which could mean many different things--beach sand, builder's sand, river sand, desert sand, etc. Do you have any idea exactly what the person used to make f-sand? I would think that would be very important since the anionic charge on the sand is what holds the MOCP to it and prevents it from being washed away in the water.

What water are you planning to purify with the f-sand and how will you measure 'purity' or potability? The f-sand is supposed to remove bacteria so you could put a drop of the water before filtering through the f-sand on an agar plate and a drop afterwards to see how well the bacteria were removed.

We will try to help you turn this into a winning project!

Sybee

Hello SciB,

I talked to one of the researchers and they said they used naturally anionic silica.

I've been trying to make sense of this website:
http://psumoringa.org/results.html

The water to test would either be from the nearest pond/not clean water source or just water I added dirt etc. to.
Instead of agar plates, do you think using one of those E. coli testing kits would be as efficient?

Thanks,
Meenakshi

Hi Meenakshi,

What is 'naturally anionic silica'? Is it something they dug up from the ground or was it synthetic? I know silica is silicon dioxide, but where do the 'anions' come from?

If you want to test for bacterial contamination in water, you need to look for all microbes--not just E coli. Just buy some nutrient agar and some petri dishes and pour some plates. There are plenty of instructions showing you how to do this on the web. I would recommend that you pour the plates yourself rather than buy them already made because you learn more by doing things yourself.

Good luck!

Sybee

Hello Sybee,

The researcher said they purchase the silica from a chemical company. Do you think it would be okay if I just bought silicon dioxide from Home Depot, or should I get it from like Sigma-Aldrich?
I also contacted a local lab to use their centrifuge to extract the MO protein from the seed powder. They want to know how many rpms the centrifuge should be set at.
Do you think a more testable/applicable question would be: How effective is the f-sand in eliminating bacteria compared to normal Moringa purifying methods? or: How many times can the f-sand be used before it doesn't have an effect anymore?

Thanks,
Meenakshi

Hi Meenakshi,

If your goal in testing the moringa protein is to develop a cheap, effective way for people in undeveloped countries to purify water, then i would not use silica purchased from Sigma. Home centers usually have something called builder's sand or sharp sand that i think is silicon dioxide. Builder's sand might be accessible to people in resource-poor areas, but i would also like to see you try some natural sand if you can find some in your area.

If you think about it, the way this system should work is for people to gather the moringa seeds, grind them up, mix them with clean water and let the particles settle out, then take the solution above the particles that contains the MOCP and mix it with sand to make f-sand. The sand could then be loaded into a large pipe capped at one end, but with a hole for water to drain out. Unclean water would be poured into the top of the pipe and clean water would come out the bottom.

You could get some PVC pipe and try setting up purification systems with various types of sand alone and with f-sand containing various amounts of moringa extract. You would then pour a measured volume of your test water through each column and collect the outflow. To see how effective the system was you would spread a drop of the water before you pass it through the system on a nutrient agar plate, then spread a drop of the water AFTER it passes through the sand. You should rinse the sand several times with distilled water before using it to wash off any bacteria or molds that might be on the sand.

This is just a suggestion about how you could do the purification and water assay. How did you plan to do it?

Oh, in regards to your question about the centrifugation, I think this may not be necessary because the person whose thesis you cited in the pdf file in your previous posting just let the particles settle out. This is how people would have to do it in a developing country. If you did want to centrifuge it, you would not need high speed. 3000 rpm for 5-10 minutes would be enough to pellet the debris from the grinding of the seeds. You could use the disposable 50 ml plastic conical centrifuge tubes that every lab has.

I hope this helps.

Sybee

Hi SciB,

Thank you very much for all of your recommendations and guidance. I feel a lot closer to completing a science fair project than I did a month ago. I'll take a trip to Home Depot this weekend to get everything, but in the meantime I'll finalize the procedure.

I also found this article: http://www.technewsdaily.com/5467-cheap ... -sand.html

I was planning on carrying out something similar to your suggestion in the previous post, and in the end testing the efficacy with the agar plates. For the design of the filter, I was thinking about building something like this:

http://www.womensglobaltoolkit.com/2013 ... signs.html

Thanks,
Meenakshi

Hi Meenakshi,

Thanks for the link to the Women's Global Toolkit--what a great site!

I couldn't tell from the picture what she used to hold the ground up seeds but it looks like it is made of plastic. If you want to go really low-tech, you could use a plastic water bottle as a holder for the f-sand. A developing country probably would not have a Home Depot in the village, but water bottles are everywhere. Just cut off the bottom of the bottle to make a filtering canister. The only thing you have to figure out is what they could put in the bottom to keep the f-sand from leaking out. A piece of fabric would probably do it.

I think your plan of making a water purifier with moringa seed extract combined with sand is a great idea. The capacity of the filter is one of the main factors in how useful it will be. If you can only put a few liters of water through it before it needs to be replaced then people are not going to use it. Maybe the sand will increase the lifetime of the filter.

One thing I am wondering is whether bacteria or algae or molds might grow on the filter after a while, especially in warm climates. This would certainly limit the effectiveness of the unit and it is something you will have to think about. The water that will be put through the filter could contain bacteria, fungi, protozoans, parasites and organic matter and these could contaminate the filter over time and make it inactive. Maybe there would be some way to sanitize it to prevent these things from growing. I think you might want to do some online searching about this problem and see if you can come up with some potential solutions.

Good luck and i am really looking forward to hearing about your project as it develops!

Sybee

Hello Sybee,

Thank you for all your suggestions. I will certainly keep them in mind. I was wondering about how the MO protein is adsorbed to the sand. I thought sand was neutrally charged. I looked up some more articles and they all said soil has a negative charge, but that is only from the organic matter/clay, and the more sand there is in the soil, the less anionic it is.

http://www.agriinfo.in/?page=topic&supe ... opicid=293
http://nmsp.cals.cornell.edu/publicatio ... heet22.pdf

I think what they used in the experiment was something like this: http://www.sigmaaldrich.com/catalog/pro ... &region=US

Do you think it would be possible to carry out the procedure using clay minerals?

Thanks,
Meenakshi

Hi Meenakshi,

I think you are just going to have to try some soil samples and see what happens. Clay does have a charge, but it is not very porous, so the flow rate through it might be very, very slow. I think a mixture of part sand and part clay would work best.

The experiment you need to do is to add a known amount of MO extract to a sample of soil then measure how much MO protein comes off when you pour water through the soil. That's simple in concept, but not so easy to do when you don't have access to a molecular biology lab and all the instruments and reagents.

What are your ideas about how to do this? How did you plan to measure the activity of your f-sand--by how well it reduced bacterial counts measured on a Petri dish? I was wondering if you could take a measured amount of MO extract, mix it with a certain volume of contaminated water then pour it through some sand or sand-clay mixture. I am thinking that the MO protein might bind to the bacteria and be filtered out by the sand so that the water that came through the sand would be drinkable. Maybe you could do some more reading about MO and see if anyone has tried it that way.

Good luck!

Sybee