Incense made with by-products from forest show promising use as insect repellent

New products made from forest waste as insect repellent? We're down for that.

The Department of Science and Technology (DOST) - Forest Products Research and Development Institute developed new products from cinnamon barks, and pili and almaciga resin — essentially processed residues or waste — that show high potential in warding off pesky insects like mosquitoes and houseflies. 

In an interview, the agency’s forester, Florena Samiano, told GMA News Online how they came up with the new products from essential oil production that can help with the seasonal rising cases of dengue. 

“Tone-toneladang waste residues din 'yung napo-produce, so ni-convert namin itong waste residue of essential oil production para makabuo ng mga insenso na pwedeng ipang-repel sa mga lamok at insekto gaya ng mga langaw din o house flies,” Samiano said. 

(We converted the waste residue of essential oil production to produce incense that can repel mosquitoes and insects such as house flies.)

From Expensive to Cost-effective Alternatives 

With their office in located in Mt. Makiling near the Forest Reserve of University of the Philippines Los Baños Forestry campus, Samiano shared how they always encounter mosquitos near nighttime.

“Around 5 p.m. onwards, 'pag dumidilim na 'yung paligid, marami na talagang lamok,” she said.

(When it gets dark, there are already a lot of mosquitoes.)

They initially tried developing disinfectants using essential oils and diffusers but they quickly realized it was expensive to produce. 

“So, naturally, there are inherent repelling properties like resins, oils, and extracts from aromatic plants. So, initially, dati po (what we did) was to mix oils in diffusers as disinfectants and repellents against mosquitoes,” she said.

“Kaso po na-realize po namin na masyadong mahal ang mga langis tapos na-observe pa nga po namin sa mga laboratory namin, every time na nag-e-extract kami ng oil ay maraming mga wastes, solid and liquid residues like spent leaves, spent barks, and spent resins, and even hydrosols na aromatic pa rin naman po ito, 

(We realized that oils are very expensive, and then we observed in our laboratories that every time we extract oil, there are a lot of wastes, solid and liquid residues like spent leaves, spent barks, and spent resins, and even hydrosols that are still aromatic.)

'Compelling Compounds' to Ward Off Insects

There are around 100 volatile compounds based on their Gas Chromatography-Mass Spectrometry (GC-MS) analysis that show the smell and repelling properties of the incense.

Some of the things that they observe are the time of burning, burning quality, fragrance, and repellency property of the products.

The test cage method showed insects and mosquitos were irritated and later on repelled when the products were burned.

“As we found out, these insects are really irritating and repelled. They don't like the smell of incense, especially those with resins,” she said.

(As we found out, parang iritable talaga 'tong mga insekto na 'to at nare-repel sila. Ayaw nila nung amoy ng usok ng insenso especially 'yung may kasamang mga resins.) 

They also found compounds such as creosol that could serve as germicide, disinfectant, and antiseptics.

“Siya rin 'yung responsible for the spicy vanilla note na maaamoy natin kapag sinusunog natin 'yung insenso,” the forester said.

(It is also responsible for the spicy vanilla note that we can smell when we burn the incense.) 

“Mayroon din siyang furfural. Kalimitan ito 'yung amoy ng nasusunog na caramel — 'yung aroma niya. Kalimitan ginagamit 'to as fumigant. It can control root infesting plant parasitics, nematodes, and fungi. Potential siyang maging nematocysts and fungicides,” she added.

(Its aroma is like the smell of burning caramel. It is often used as a fumigant. It can control root infesting plant parasites, nematodes, and fungi. It has the potential to be nematocysts and fungicides.)

Meanwhile, the almaciga resin has derivatives of benzene and naphthalene which are used as insecticides, while the elemi resin compound also contributes to citrusy, woody, and camphor odor.

“Sa fragrance naman 'yung contribution niya para hindi masakit sa ilong, medyo kaaya-aya 'yung amoy niya,” she said.

(As for the fragrance, it doesn't hurt the nose, it’s smell is quite pleasant.)

Help for Health and Environment 

As the incense cones and sticks are made out of waste and residues, Samiano assured the public that the product is all natural and could help with the environment.

“Natural 'to. Wala itong kumbaga ay synthetic na chemicals na masasabi tsaka gamit pa 'yung mga waste materials kung tutuusin kumbaga in-optimize pa natin 'yung diba medyo scarce 'yung resources natin in terms of mga barks, resins from the forests trees, mga puno at halaman pero dapat ma-prolong pa natin 'yung kanyang utility,” the forester said.

(This is natural. It doesn't contain any synthetic chemicals, and we use waste materials. In fact, we have optimized it. Our resources are quite scarce in terms of barks, resins from the forest trees, trees and plants, but we should be able to prolong its utility.)

“Kung tutuusin, ang usual practice tinatapon lang 'tong mga 'to pero may aroma pa siya at gusto nating i-optimize 'yung gamit ng mga materials para hindi naman siya agad mapupunta lang as basura parang prolonging 'yung the whole value chain of the commodity na katulad nitong mga non-timber forest products of leaves, barks, resins, and other parts of trees or plants,” she added.

(In fact, the usual practice is to just throw these away, but they still have an aroma and we want to optimize the use of materials so that they don't just end up as waste, like we prolong the whole value chain of the commodity of these non-timber forest products of leaves, barks, resins, and other parts of trees or plants.)

“Kaunti rin kasi 'yung nakukuhang essential oils sa mga ito kaya medyo mahal ang mga essential oils. Might as well, i-utilize pa rin natin nang mas maigi itong mga by-products of essential oil production para mas maraming life of the value chain 'yung ma-optimize natin, mas maraming makikinabang, mas maraming kita for the industry,” Samiano said. 

(There is also little essential oil obtained from these, which is why essential oils are quite expensive. Might as well, let's still utilize these by-products of essential oil production more efficiently so that we can optimize more of the life of the value chain, more benefits, more profits for the industry.)

“Pwede pa natin siyang i-explore further to promote 'yung green energy na katulad nito, natural products pa,” she added. 

Samiano hopes this project could help in the effort to lower cases of dengue in the country.

“Mayroon siyang (contribution) for the health prevention na mag-lower 'yung dengue cases kung mayroon tayong mga ganitong uri ng produkto,” she said.

(It has a (contribution) for the health prevention that dengue cases will be lower if we have these types of products.)

As of writing, Samiano said they are processing the pilot study of the products to see if the production of the goods are doable in their adaptors along with the licensing, patenting and they are hoping towards its commercialization. 

“Although, may mga uses ito (forest products), makakatulong na bukod sa makuha natin 'yung pinaka-ultimate na gamit niya like for the case of what we are studying sa mga essential oils and extract,” she said.

(Although, they (forest products) have uses, they can help us get the ultimate use of them like for the case of what we are studying in essential oils and extracts.)

“Huwag nating itapon 'yung mga by-products ng waste residues. Hanapan pa natin siya ng mga gamit. Ang DOST ay nagpo-promote ng circular economy approach para i-prolong nga natin 'yung gamit ng mga resources para mas maraming maraming makinabang at kakaunti na lang 'yung maibabalik natin as basura sa kapaligiran.”

(Let's not throw away the by-products of waste residues. Let's find uses for them. DOST is promoting a circular economy approach so that we can prolong the use of resources so that more people can benefit and we can only return a little as waste to the environment.)

— LA, GMA Integrated News