Local scientists have discovered the potential of non-edible parts like stems, leaves and roots of selected indigenous crops as essential ingredients of cosmetic products, medicine and pesticides.
“Vegetable crops such as ampalaya, singkamas, sitaw, bataw, saluyot, eggplant, garlic, onion and tomato can be sources of phytochemicals or bioactive substances such as alkaloids, flavonoids, and saponins – substances that are essential in the production of environment-safe and natural-based cosmetics, medicine and pesticides,” the Department of Science and Technology (DOST) said in a statement.
DOST said these phytochemicals possess medicinal, antipyretic, analgesic, and cytotoxic or pesticidal properties.
“Crop wastes were also found to have cellulose substances or pulp that can be used for papermaking,” the DOST said.
DOST said these were the findings of a recent study entitled, “Investigation of selected agricultural products and wastes in Region III as sources of natural products and pulp” by a team of researchers at the Central Luzon State University led by Lilia Torres.
The study was conducted under the supervision of the Philippine Council for Agriculture, Forestry and Natural Resources Research and Development, an attached agency of the DOST.
DOST said alkaloids have strong anti-bacterial and anti-cancer biological activity and are widely used for drug and herbal formulations.
Flavonoids, on the other hand, act as potential antioxidants and anti-aging agents in cosmetic products. These have anti-viral, anti-inflammatory, and cytotoxic activities that inhibit growth of microorganisms such as bacteria and fungi, the DOST said.
Saponins are surface-active agents producing foamy suds when mixed with water. These are used as ingredients for cosmetics, detergents, shampoos, emulsifiers, and fire extinguishers.
“Saponins exhibit hemolytic properties, which act as poison, show cytotoxic or pesticidal activity, and have a variety of medicinal applications. They can inhibit growth of cancer cells, lower cholesterol, boost immune system and energy, act as natural antibiotic, anti-inflammatory, and anti-oxidant,” the science department said.
The study found that extracts from the seeds of ampalaya contain alkaloids, flavonoids, and saponins, which have insecticidal property against fruitfly. The same phytochemicals extracted from the seeds of singkamas are also effective as insecticide against green leafhopper, the DOST said.
Researchers also discovered that saponin extracts from the stems, roots, and leaves of the Apollo tomato variety have insecticidal property against the brown planthopper. The extracts also contain an anti-tumor agent, the DOST said.
On the other hand, the study found that extracts from the leaves, stems, and roots of the native tomato variety contain saponins that have antibacterial action against disease-causing bacteria called Escherichia coli and Staphylococcus aureus, it said.
Researchers also found that extracts from the seeds of bataw contain saponins and alkaloids with anti-tumor agent, the DOST said.
The study showed that the leaves, pods and seeds of saluyot have alkaloids, saponins, and aromatic groups with anti-mutagenic property that can prevent mutation of cells that can lead to cancer, the DOST said.
DOST said the study found that the leaves, stems and fruits of Dumaguete Long Purple eggplant variety contain saponins with pesticidal properties, while saponin extracts from the leaves, fruits, and stems of Nueva Ecija Green eggplant have antipyretic property that can lower fever similar to the action of aspirin.
The research also found that cloves of native garlic contain aromatic and aliphatic groups that can prevent formation of the fungi Aspergillus flavus or molds usually found in peanuts and corn, and in processed foods such as cheese and milk.
“The garlic extracts can also fight bacterial pathogens Escherichia coli and Staphylococcus aureus,” it said.
The flavonoid and saponin extracts from the bulb of red onion exhibit antibacterial properties against Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa, according to the study. Extracts from the skin and bulb of yellow granex onion were found to have antipyretic and mild analgesic or pain relieving properties.
DOST said local researchers also discovered that the leaves, vines, flowers, pods, and roots of sitaw contain saponins and flavonoids with fungicidal property against rice fungi, Pyricularia oryzae.
DOST said the study also found that the vines of ampalaya and rice straw are potential sources of pulp for papermaking.
“Paper from ampalaya is tougher than rice straw paper. The Philippine Seed Board rice varieties that can be used for rice straw papermaking are PSB Rc24, 40, 60, and 62. PSB Rc24 variety produces the brightest and thickest paper, most resistant to ink penetration, and least resistant to water penetration,” according to the study.