Aloe vera, scientifically known as Aloe barbadensis, has a history of use in treating skin issues, supporting digestion, and aiding wound healing. Despite the popularity of aloe vera gel, the discarded peels have had limited use in the past and and were treated as agricultural waste.

However, scientists from the American Chemical Society have recently identified bioactive compounds in these peels that repel insects from crops, opening up the possibility of using the waste product as a natural insecticide.

Presenting their findings at the American Chemical Society (ACS) Fall 2023 meeting, the scientists highlighted the value of aloe peels in preventing bugs and insects from damaging crops. Dr. Debasish Bandyopadhyay, Ph.D., the project's principal investigator, emphasized the vast global disposal of aloe peels annually and the need to utilize them effectively. Dr. Bandyopadhyay initially became interested in the insect-repelling potential of aloe vera after observing insects avoiding aloe leaves at a local production centre.

“It’s likely that millions of tons of aloe peels are disposed of globally every year. We wanted to find a way to add value,” Dr Bandyopadhyay said in a press release.

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Industrial-scale disposal of aloe peels as biomass is a significant contributor to environmental issues, primarily because the decomposition of the agricultural waste releases methane and other greenhouse gases.

To investigate the insecticidal properties of aloe vera peels, the researchers dried the peels in the dark to preserve their bioactivity. Extracts were then produced using various solvents and chemical profiling was used to identify over 20 compounds from the extracts, including six with known insecticidal properties.

These compounds, such as octacosanol and quillaic acid, could contribute to the insect-repelling effects of aloe peels. Importantly, they were also found to be non-toxic, addressing safety concerns. Ongoing investigations into methanol and aqueous extracts also show strong insecticidal activity.

The next step involves field testing to evaluate the effectiveness of these compounds against agricultural pests. Additionally, researchers are exploring the potential anti-mosquito and anti-tick properties of these compounds, which could lead to the development of a natural insect repellent for consumer use. Dr. Bandyopadhyay envisions creating an insecticide that avoids harmful synthetic chemicals, benefiting both agriculture and the general public.