Loofah Plant Seeds Absorb Organic Pollutants and Heavy Metals from Wastewater

Seeds and oils from the plant that produces the loofah sponge could help purify wastewater and prevent the spread of waterborne diseases in the developing world, according to a scientist speaking today at the 17th Annual Green Chemistry & Engineering Conference in Bethesda, Md. The low-cost, biodegradable seeds and substances made from oils of these seeds are particularly effective at absorbing heavy metals and other potentially harmful organic compounds from polluted water, he said.

Adewale Adewuyi, Ph.D., a lecturer at Redeemer’s University in Mowe, Nigeria, notes that rain water, rivers and streams are the most common direct sources of drinking water in many developing countries. Often, this water is polluted with substances from factories and agricultural runoff, which can harm both people and animals. In 2010, for instance, lead poisoning in Nigeria — which was later linked to industrial wastewater — claimed the lives of more than 500 children in less than seven months, he reported.

Absorbents, such as activated carbon, can help absorb these pollutants from water. However, they work slowly, are only effective in a limited pH range and are expensive. To help overcome this problem, Adewuyi turned to the seeds of the Luffa cylindrica plant. This plant, commonly known as sponge gourd, produces sponge-like fruit — loofahs — that are used as bathing brushes by millions of people worldwide. But Adewuyi says the seeds, which are plentiful, are considered environmental waste. As a result, they are underutilized.

In laboratory tests, he isolated oil from L. cylindrica seeds and used it to produce detergent-like substances called surfactants. These surfactants enhanced the seed’s absorption capacity in cleaning wastewater. He found the new product was cheaper and more effective than existing absorbents. Adewuyi is currently exploring whether other underutilized seeds and oils could have the same effect.

“It’s a win-win process,” he says. “It’s cost-effective, green, reproducible and, of course, applicable in developing countries because it is very easy to start up and maintain.”

Article appearing courtesy Celsias.