by Melody M. Aguiba
March 5, 2014
The Philippine government may soon be able to avail of a cost-effective aflatoxin detection kit critical to food safety for feeds involving mainly the P100-billion corn sector and also for peanut as direct food.
The detection kit, costing only $2 to $3 per sample, is being released to the market by the International Crops Research Institute for the Semi Arid Tropics (Icrisat).
“We’r e in the process of releasing our detection to the market. We’re discussing with companies, with our agribusiness incubator,” according to Hri Kishan Sudini, Icrisat, groundnut pathology expert, in an interview.
The aflatoxin detection kit will give Filipino farmers the advantage of selling their corn and peanut at a high price as the market pays a premium for food safety.
Such detection kits will be crucial as the Philippines is aggressively seeking to export its corn after initial export of corn silage to South Korea last year.
“Aflatoxins are an important group of mycotoxins and pose a serious threat to food safety. More than 75 percent of the countries in the world have their own regulations on aflatoxins, indicating the level of concern (on aflatoxin),” according to Sudini.
Aflatoxins create molds in corn, peanut, and other farm commodities like copra (coconut meat) and tree nuts (pistachio, almond) that become cancer causing.
This makes it a serious concern especially for developed countries that want to import farm products.
And developing countries like the Philippines are more known to have inappropriate post-handling processes for farm products that may become aflatoxin-contaminated.
The kit may enable Filipino farmers to pay just at least one-fifth per sample of the commercial price for the kit.
“There are several commercial kits in the market from different companies. For each action, you pay at least $10. So if you can buy one kit which is $500, you can only analyze 50,” he said.
A technology to detect aflatoxin in animals’ body or meat or in animals’ milk which may cause toxins on human when taken in has also been developed by Icrisat.
This aflatoxin is in the form of aflatoxin M1. The detection kit can be highly sensitive and can detect aflatoxin M1 at a rate of 0.5 micrograms per kilo. It can also detect other toxins produced by aspergillus species of fungi.
“This suggests that these assays meet global standards for screening food samples,” said Sudini and Icrisat researchers C.L.L. Gowda, F. Waliyar, and S.V. Reddy in a report.
A combination of technologies is being promoted by Icrisat to ensure food safety by preventing aflatoxin contamination of food.
One is orienting farmers that corn or peanut plants should not be left several days in the field upon harvest without sending them to dryers.
“The most important thing is proper drying to eight percent moisture,” he said.
The plants are contaminated by the soil, which is why soil sterilization is also one management practice.
Storage of farm products is guarded.
Icrisat is specifically concerned about post harvest handing of peanuts as peanuts are now considered climate smart crop that can withstand more serious drought in these times of climate change.
Proper storage is important since insect pests do mechanical damage or holes on farm goods
through which the fungus aspergillus causes aflatoxin on the peanut.
“If you’re able to prevent insect damage during post harvest , you can reduce aflatoxin contamination,” he said.
Icrisat has also engaged in breeding of peanut varieties that have aflatoxin- resistance.
”Aspergillus can enter into peanut pod while still in the soil. That’s why we’re focusing on breeding also. We’re breeding cultivars which cannot allow aspergillus to enter into peanut pod.”
Aside from resistance to aflatoxin, the varieties should be high yielding. These varieties should yield at least three metric tons per hectare as that of peanut variety ICGV 9114.
Researchers are identifying genes responsible for resistance to aflatoxin.
A peanut variety that may have aflatoxin-resistance may be one that has tough coat which stops aspergillus from causing aflatoxin formation.
“If the seed coat is in good health, it will not allow the fungi to enter into the peanut seeds. That’s one important aspect breeders are looking at,” said Sudini.
Another peanut variety may have biochemical factors, such as oil content, that will prevent the fungus from entering the seed.
There are also important mechanisms inside peanuts that may prevent aflatoxin development.
“Inside peanut seeds, there are factors that will keep the fungus from producing the aflatoxin
like the phytoalexins,” said Sudini.
Phytoalexins may be generally considered phytochemicals that form plants’ defense against stresses from outside including fungus infection.
“Whenever the aspergillus fungi enters peanut seeds ,there is one phytoalexin called resveratrol. It’s a very important phytoalexin that can be in peanut and grapes. If you have high content of resveratrol in peanut seeds, that can restrict aflatoxin contamination,” he said. End