- Sago is the most developed of the group of palms that provides a perennial source of staple crop. Sagos are multi-stemmed palms, and when cut down on maturity, it leaves behind an undamaged clump for future productivity. Trunks yield carbohydrates and fibers. Established after 5 to 7 years, a one hectare sago stand can yield 25 tons or more of edible starch indefinitely.
- Word sago is originally Javanese, meaning starch containing palm pith. In other languages, it has become a common name for various sources of starch or starch of any palm. (23)
- The scientific name derives from Greek words metra, meaning pith of the tree or parenchyma, and xylon, meaning wood, referring to the large amount of internal pith. (13)
Sago is a palm tree of medium height, throwing up stems in succession, each stem in turn flowering, fruiting and dying after about 15 years. Leaves are pinnate, 6 to 9 meters long. Leaflets are linear-ensiform, up to 1.5 meters in length. Spadix is 3.5 to 4.5 meters long, the spathes quite spineless. Spikes are 10 to 12 centimeters long and about 1 centimeter in diameter. Fruits are globular, slightly depressed, with about 5 millimeters of pericarp, spongy and succulent mesocarp, and thin endocarp. Seeds are globular, depressed, with white, bony albumen.
Sago palm is hapaxanthic, i.e., it flowers only once during its life; after fruiting, leaves senesce and the plant dies. (13)
- Abounds in fresh-water swamps at low altitudes in Mindanao, and planted in some parts of Cebu, Bohol, Siquitor, Mindanao, Basilan and Sulu.
- Native to Fiji, Indonesia, Malaysia, Papua New Guinea, Singapore, Solomon Islands, Thailand. (13)
- Contains 80% starch, 16% water, 2% nitrogenous substances, and very little ash.
- Nutrient analysis in (g) per bole and one leaf: N 590 (one bole) / 37 (one leaf), P 179 / 6, K 1799/20, Ca 860/90, Mg 350/7/ (19)
Nutritive and easily digestible, free of any irritating properties.
- Nutritive, easily digestible.
- Sago grub is raised as by-product of sago starch production.
- In parts of Southeast Asia, the boles used to obtain starch. Hot water poured over slightly sour, wet starch is stirred into a glue-like mass eaten with fish and vegetable dishes.
- Palm heart and young leaves used as vegetable.
- Fully ripe fruit
astringent, but eaten as a delicacy by some. (27)
- Sago pearls used to prepare 'three palm pudding': sago pearls cooked in coconut milk, and topped off with sugar from sugar palm (Arenga pinnata). In Sarawak, pearls are prepared from sago palm starch, mixed with rice bran.
- Food used during fevers and convalescence.
- In Malaya, recommended as an excipient in making poultices for shingles.
- In Papua, New Guinea, stem sap is applied to forehead to ease headaches. Starch from plant trunk mixed with water and drunk for diarrhea and stomach pains. Starch paste applied to burns. Leaf used to cover fresh or infected sores until they heal. Liquid starch given to newborns to treat enlarged spleen.
- In Sindh, a polyherbal formulation of polymenorrhea includes M. sagu: 3-4 sabudana (M. sagu), 3-4 choti ilaichi (E. cardamomum), and misri (crystal sugar), mixed and boiled in milk, taken half a glass twice daily for 5 to 6 days. For menorrhagia: soak zeera (Cuminum cyminum L.) and sabu-dana (Sago) (Metroxylon sagu Rottb.) in half glass water over night, taken orally in morning at fasting for 7 days.
- Used as traditional antifertiity medicine by Dayak people in Central Kalimantan.
- In South Kalimantan, fresh roots of sago traditionally used as antidiarrheal. (25)
- Poison: Fruit reportedly used as a poison in Malaya; the sap mixed with Datura by prisoners.
- Stabilizers: Sagu starch used in food production (high fructose syrup, MSG, maltodextrins, cyclodextrins); manufacture of paper coating, adhesives and biodegradable filler in bioplastics.
- Sago grub: Sagu grub raised as by-product of sago starch production, with stumps and stem tops left in the field for insect colonization. In parts of New Guinea, grubs are eaten in small quantities in the daily diet.
- Fodder: Ground pith sometimes used as animal feed, especially for pigs; when dried, for horses and chickens.
- Fiber: Processed pith yields a starch to produce fiber; leaves also yield a fiber used for making mats.
- Thatching and other uses: Fronds of palm used for thatching. In West Java, the palm is grown especially for leaf production. The rachis of fronds often used for walls. Bark used as floor material or fuel.(19)
- Brooms: In the Philippines, rachis from fronds used for making walis-na-tingting.
- Grubs: In decaying trunks, grubs, especially Rhynchophorus spp., may grow, which are considered delicacy by all sago growers. Grubs are eaten fresh or roasted. They yield 6.9% protein, 8.5& carbohydrate, 11.3% fat, and 0.7% ash. (19)
- Fertilizer: Waste from pith processing used as fertilizer. (27)
- Construction: Bark used as flooring material. Hard outside of the trunk used for building purposes. (27)
- Fuel: Dextrose sugar extract from sago palm starch can be processed to yield ethanol. Cortex of the trunk used for firing in paper mills. Dried bark may be used as domestic fuel. (13)
• Glycemic and Insulinaemic Responses: Study investigated the effect of different forms of sago supplementation on plasma glucose and plasma insulin responses, as compared to white bread supplementation in man, during resting state. Results showed sago paste and porridge may be used for supplementation before and during exercise, and sago gel after endurance exercise during recovery process. (1)
• Inexpensive Lactic Acid from Sago Palm: Dulce Flores, a researcher from the University of the Philippines in Mindanao discovered a new streptococcus strain called Enterococcus faecium with the capability of converting sago starch directly into lactic acid without the costly pre-enzymatic treatment. Lactic acid is a colorless acid found in sour milk; used as a preservative in dyeing and in making adhesives and pharmaceuticals. (17)
• Antioxidant / Cigarette Smoke Exposure: Study showed Sagu aqueous extract supplementation has a protective effect in reducing free radicals released from sidestream cigarette smoke before causing extensive damage to the tissues. SAE supplementation might have a beneficial role in protecting smokers and non-smokers exposed to sidestream cigarette smoke. (4)
• Nitrogen Fixation: Study evaluated the presence and contribution of diazotrophic bacteria to nitrogen concentrations in sago palm starch. Nitrogen fixation were considered too low to be of nutritional benefit. Sago starch does not add significantly to protein calorie intake and may be associated with susceptibility to nutritional-associated illnesses. (9)
• Antibacterial / Skin and Wound Pathogens: Study evaluated the antibacterial activities of Thai medicinal plant formulas and their components against skin and wound pathogens. Except for E. coli and MDR E. coli, M. sagu demonstrated the strongest antibacterial activity on both gram-positive and gram-negative pathogens including MDR strains. (14)
• Antifertiity Effect: Study evaluated four plants viz. Metroxylon sagu, B. balsamifera, C. tigliu, and F. racemosa for antifertility effects on Swiss Webster mice. All the plant extracts antifertility effects, with the decrease in corpus luteum and fetuses attributed to inhibition of folliculogenesis. (15)
• Adsorbent for Oil Spills: Waste material generated by Malaysia's sago palm industry has potential for use as adsorbent for cleaning up oil spills. When sago waste is chemically modified using fatty acid derivatives, it becomes more hydrophobic, i.e., less affinity for water and an excellent affinity for oil. (16)
• Stabilizing Agent in Yoghurt: Yoghurt with 0.25% concentration of Metroxylon sagu contributes to firm body texture, decrease in whey separation, increase viscosity and increase in shelf life. (18)
• Latent Polyphenol Oxidases: Study reports on the extraction, partial purification and activation of latent polyphenol oxidase (LPPO), an enzyme responsible for the browning reaction of sago starches during processing and storage. The LPPO was highly reactive toward diphenols and triphenols. Enzyme activity was greatly enhanced in the presence of trypsin, SDS, ethanol, and linoleic acid. (21)
• Antioxidant / Decoction and Leaves: Study searching for natural antioxidants from Philippine medicinal plants evaluated decoction and ethanol extracts of leaves of Ficus nota, Metroxylon sagu, Mussaenda philippica, Inocarpus fagifer, and Cinnamomum mercadoi. M. sagu decoction (403.00 mg GAE, 96.39 AAE, 139.61 BHTE) and ethanol extract (310.58 mg GAE/g, 73.49 AAE, 102.36 BHTE) showed the second and third highest amount of phenolics, strong free radical scavenging against DPPH and high antioxidant capacities, respectively. (22)
• Immunomodulatory / Water Soluble Polysaccharides: Study investigated the immunomodulatory activity of water soluble polysaccharides isolated from M. sagu using three different in-vivo experimental models of immunosuppression in rats. The WSPS showed dose-dependent stimulation of immunity in the animal models. However, it was more efficacious against ethanol-induced immunosuppression. (24)
• Antibacterial / Antidiarrheal / Roots: Study investigated the antibacterial effect of sago root infusion in Salmonella typhi induced diarrhea and in male mice with castor oil induced diarrhea. Results showed antibacterial activity and reduction of frequency and duration of diarrhea. The best concentration of the infusion was 20%. (25)
• Nanoparticles / Antibacterial: Study reports on a fast and simplified green synthesis method for the production of AgNPs via autoclaving. The synthesized AgNPs exhibited great antibacterial activities against Gm+ Micrococcus luteus and Gm- Escherichia coli. Results suggest potential application as antibacterial agent in various applications especially biomedical devices. (26)