By: Azman Zakaria
Photo: Noor Azreen Awang
SERDANG: A team of researchers from Universiti Putra Malaysia (UPM) have successfully produced edible coating derived from local stingless bee honey or kelulut honey to control Anthracnose disease (post-harvest fungus) for a variety of agricultural produce, including papayas.
Kelulut honey was formulated into powder form before being used. Ten grams of kelulut honey could produce ten grams of powder that can be used on 100 papayas.
The papayas were dipped in kelulut honey as the coating.
Besides controlling disease, it also helps to preserve and prolong the quality of papayas between 14 to 21 days from harvest, which will ease the export process.
Leader of the research team, Assoc. Prof. Ir. Dr. Norhashila Hashim, said her team has tested kelulut honey from Malaysia at different concentrations and found that the honey has the potential to inhibit or stunt the growth of miselium Colletotrichum sp.
Colletotrichum sp. is a fungus that could cause Anthracnose disease which would damage the quality of agricultural produce such as papayas, mangos and chillies.
She said the scan using the electronic microscope scanner showed that there are signs of spores’ destruction and degradation of hyphae fungus when treated by kelulut honey with a concentration of 15 per cent.
“We also detected kelulut honey has some phenolic content (gallic acid, coumaric acid, ferulic acid and salistic acid) and flavonoid content (naringenin and kaempferol) which contribute to the anti-fungal properties.
“Therefore, its function as a coating for agricultural produce is indeed more efficient,” she added.
According to Dr. Norhashila, papaya is chosen for research to identify the function of kelulut honey as an edible coating due to its physicochemistrical properties apart from the fruit’s climacteric properties.
It has a short shelf life due to the climacteric ripening pattern and perishable threat after harvest; thus, it can provide a more significant research impact.
Assoc. Prof. Ir. Dr. Norhashila, who is also Head of the Department of Biological and Agricultural Engineering, Faculty of Engineering, UPM, said the papayas dipped in kelulut honey were stored at 12 ± 1 degree Celsius for 12 days.
“The research results found that the papaya sample coated with kelulut honey with a concentration of 15 per cent managed to preserve the freshness, colour and soluble solids content.
“Net weight, sample respiration rate and ethylene production of the papayas had also dropped throughout the storing period,” she said.
Hence, kelulut honey can improve the quality of papayas after harvest and increase the shelf life of fruits.
She added that her team has also published the results in Elsevier: Journals of Materials Research and Technology about the potential of kelulut honey in producing nanosize calcium oxide.
The nanoparticles were obtained from biosynthesis through the methods of sedimentation and precipitation of calcium carbonate in kelulut honey. The nanoparticles produced through biosynthesis have the maximum inhibition effect on Anthracnose disease.
“As evident in the cytotoxic test on MRC 5 and Vero cells, the nanoparticles were found non-toxic to humans. Thus, it is safe and edible,” she added.
She mentioned that the research offers a safer approach for nanoparticle preparation by using kelulut honey for different applications in the agricultural field and food.
According to Dr. Norhashila, papayas have been coated with a lot of chemicals all this while and can be harmful to health in the long run.
The innovation won a gold medal at the UNIMAS Innovation and Technology Exposition, in Kuching, Sarawak in 2019 and a bronze medal at the Faculty of Engineering, UPM exhibition in 2019.
The research started in 2017 and ended in 2019. Besides her, five other members of the research team are Dr. Bernard Maringgal, Dr. Intan Syafinaz Mohamed Amin Tawakkal, Dr. Muhammad Hazwan Hamzah, Prof. Dr. Mahmud Tengku Muda Mohamed and Azri Shahir Rozman. - UPM
