Guaje pods grow from a tree known as Leucaena leucocephala.

leucocephala (“leu” meaning white from the Greek “leukos” and “cephala” – head refers to the flowers)

also known as cuaje, huajes, hauxya, huaxin, guash, guashe (Chiapas), guaje beans, cacalas, cascalhuite, Leadtree, White Popinac, Wild Tamarind or River Tamarind; Uaxim (Maya), ipil ipil (Philippines), Narendhar (India), Safed babul (Hindi), White Babool, Yin He Huan (Chinese)

When the Spanish arrived in southern Mexico in 1521, they found a region called Huāxyacac, the Nahuatl word for the pod of the tree Leucaena leucocephala. Not being able to easily pronounce the word they renamed the region Oaxaca.

Guaje are native to the West Indies, the Yucatan Peninsula and the Isthmus of Tehuantepec in southern Mexico and the northern region of South America. It can now be found growing in California, Texas, Florida, Australia, Brazil, Hawaii, Thailand, Indonesia and the Philippines. It is believed to be introduced into Asia through the Philippines by the Spanish via the Manila galleons

The tree produces long, flat, green pods filled with seeds about the size of a small lima bean which are used in Latin American cooking. The pod and seeds have a garlicky quality, and fresh pods are often chopped up and used to flavour various dishes. When the pods dry and turn brown, the seeds are scraped out and can be eaten raw or added to salads or cooked dishes. The seeds are often ground and used as a thickening for cooked sauces. Roasting or frying the seeds prior to use will enhance their flavour and impart a subtle sweetness to the seeds. Fresh or dried guaje can be purchased at Latin American markets.

People distinguish three types of guaje according to their qualities:

1. ‘guaje de vasca’ (vomitive guaje) which is toxic because of its high levels of secondary chemical compounds.
2. ‘guaje amargo’ (bitter guaje) which is slightly toxic but edible after being roasted, presumably with lower levels of secondary chemical compounds than the ‘guaje de vasca’
3. ‘guaje dulce’ (sweet guaje) that is edible raw, presumably because it has even lower levels of secondary chemical compounds than the other variants.

People tend to eliminate ‘guaje de vasca’ trees to prevent sickness in children. Sweet guajes and guajes with larger pods and seeds are preferred. These trees are allowed to remain where they are found and individual trees are protected and encouraged to grow in situ. Others of this tree are cultivated in home gardens (Casas & Caballero, 1996).

Almost every part of the L. leucocephala tree is consumed as human food and has been since the time of the Mayans. In Thailand and Central America, people eat the young leaves, flowers, and young pods in soups, salads and salsas
In Indonesia the leaves, flower buds, pods and seeds of this tree are eaten. The young leaves, flower buds, young pods and seeds are eaten raw as a salad (lalap/lalab). The half ripe seeds are used in botok, a traditional Javanese dish made from shredded coconut, beef or fish, and wrapped in banana leaf and steamed. The seeds of ripe pods are roasted and eaten with rice. In Java, seeds are fermented into a type of tempe (1).
In the Philippine Islands, the young pods are cooked as a vegetable and roasted seeds are used as a substitute for coffee. The young dry seeds can be popped like popcorn.

1. a traditional Indonesian soy product made from fermented soybeans.

The seeds are being considered as a non-conventional source of protein .

Guaxmole (also known as “huaxmole” or “mole de guaje”) is a dish that is prepared with guaje seeds

Huaxmolli (from the Náhuatl words “huaxin” (guaje) and “molli” (stew/cooked dish).

• 500g pork ribs cut into small pieces
• 1/3 white onion coarsely chopped
• 500g coarsely chopped tomatoes
• 1/3 white onion coarsely chopped
• 4 cloves of garlic
• 2 tablespoons lard
• 300g guaje seeds
• 6 serrano peppers (more or less depending on your preference for heat)
• 6 large cilantro sprigs
• 8 corn tortillas

Instructions

1. In a medium size pot, barely cover the meat with water, add the onion and salt and cook over low heat until it is half cooked. Drain meat and save the broth.
2. Blend the tomatoes with garlic and onion in a blender until you have a smooth puree.
3. In a skillet heat the lard and sauté the meat. Top with tomato sauce and cook over fairly high heat about 10 minutes, until it is well cooked and has reduced slightly.
4. Puree chiles with a cup of broth until mixture is smooth. Gradually add the guaje seeds and continue to blend until mixture is smooth.
5. Add this to the pan along with another cup of broth, cilantro and salt to taste and simmer, stirring and scraping the bottom of the pan to prevent sticking (for about 45 minutes). The sauce should have a medium consistency, add more broth or water if you need to dilute it.

Salsa de Guajes

INGREDIENTS

• 1 large handful of guaje pods, shelled (which is about 1/2 cup of guaje seed)
• 4 medium size tomatillos (husked and rinsed)
• 2 – 4 serrano chiles (or to taste)
• 1-2 cloves garlic (to taste)
• sea salt (al gusto)

Method

1. Using a comal or a dry frying pan (don’t add any oil when frying) placed on medium-high heat, roast the tomatillos, garlic cloves and chiles until slightly charred, be sure to turn the tomatillos and chiles so they roast evenly.  Put aside to cool.
2. Separately toast the guaje seeds, stirring constantly so they do not burn. This will not take long.  Once they begin to pop take them off the heat.  Set aside to cool.
3. Once the tomatillos are cool cut them into quarters.  Once the chiles are cool remove the stems and scrape off any charred skin (leave a few charred bits in for flavour). Do not wash the peeled chiles
4. Place the tomatillos, chiles, guajes, and garlic in a food processor or blender.  Pulse until you have a thick salsa. Do not blend it completely smooth.  If you use a molcajete, work in batches to grind the ingredients into a thick/chunky.  
5. Salt to taste. 

WARNING (?)

The leaves of this plant contain an antinutrient called mimosine. Mimosine is found distributed in all parts of the plant but the young leaves have the highest content (Soedarjo and Borthakur 1996). There are concerns that consuming this plant may lead to toxicity caused by the ingestion of mimosine (1). This issue can largely be resolved by cooking in metal pots. If leucaena containing soups and stews are cooked in iron pots, the mimosine is detoxified by complexing with the metal in the pot. Mimosine may cause hair loss. This can also be seen in animals (except for goats) who forage on the leaves. One of the symptoms of mimosine poisoning is hair loss.

1. Mimosine or leucenol is a toxic non-protein amino acid chemically similar to tyrosine, that was first isolated from Mimosa pudica. It occurs in a few other Mimosa spp. and all members of the closely related genus Leucaena. It is found in the seeds, foliage and stems.

The leaves of Leucaena are highly nutritious for ruminants and provide a good source of forage and fodder for cattle. However, the leaves which contain mimosine, are toxic to horses that eat them.

Medicinal use

Actions – abortifacient, alexeteric, anthelmintic, anti-androgenic, antibacterial, anti-dysenteric, antihistaminic, antipyretic, anti-proliferative, antidiabetic, anticancer, anti-inflammatory, antimicrobial, antioxidant; antitumor, astringent, cancer preventive, demulcent, diuretic, emollient, expectorant, haematinic, nematicide, pesticide, hypocholesterolemic, hepatoprotective, styptic, thermogenic, tonic, vulnerary (Zayed etal 2016).

L. leucocephala seeds have great medicinal properties and are used to control stomachache and as contraception and abortifacient (Meena Devi 2013). In Latin America a decoction of bark and roots is used as a powerful emmenagogue and in the West Indies it has been used as an abortifacient.

Diabetes

Leucaena is often used as an alternative, complementary treatment for diabetes (Salem etal 2011). Leaf and seed extracts have antidiabetic activity (Adekunle & Aderogba 2007). An aqueous extract derived from its boiled seeds was taken orally to treat Type-2 diabetes  (Joshi & Mahajan 2003) this treatment was also noted in Indonesia (Dalimarta 2006). The seed extract from L. leucocephala inhibits elevated blood glucose and lipids levels but increases the number of pancreatic islets (Syamsudin & Simanjuntak 2006). Although the seed extract from L. leucocephala exhibits antidiabetic and antioxidant activities and can be used for the treatment of diabetes without affecting hepatic function, there is an impact on renal function (Syamsudin & Simanjuntak 2006). The antioxidant activity is likely due to the phenolic content. An application of this extract should be considered as it can affect renal function by reducing the levels of albumin, ALP and total protein (Chowtivannakul etal 2017)

Antimicrobial actions.

L. leucocephala seed oil extract had a concentration-dependent activity against both Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Esherichia coli) bacteria (Aderigbigbe etal 2011). It has been used in traditional medicinal practices for intestinal parasitism (ascaris and trichinosis) and in China the seeds have been consumed to remove round worms. Seed extracts have also demonstrated anti dengue and yellow fever actions (Abd Kadir etal 2013). Seeds and leaves have been used to treat dysentery. Grind and consume the fresh seeds (usually as an ingredient in a salsa) or make a decoction by boiling a tender sprig of the plant in 1 litre of water for 12 minutes. Drink 1 cup.

Anti-cancer

Methanol extracts of leaves of L. leucocephala showed anti-inflammatory and antitumor activity (Zayed & Benedict 2016) and hexane, petroleum ether and ethyl acetate extracts of leaves of L. leucocephala showed antitumor activity (Zayed & Benedict 2016). Mimosine has been found to inhibit the proliferation of liver and lung cancer cells and can enhance the effect of chemotherapeutic drugs.

Medicinal actions of Leucaena constituents.

Compound	Secondary Metabolite	Therapeutic Action
Phytol	Diterpene	Antimicrobial, anticancer, cancer preventative, diuretic, anti-inflammatory
Squalene	Triterpene	Antibacterial, antioxidant, antitumour, cancer preventative, chemopreventative, immunostimulant, lipoxygenase inhibitor, perfumery, pesticide, sunscreen
n-Hexadecanoic acid	Palmitic acid	Antioxidant, hypocholesterolemic, nematacide, pesticide, antiandrogenic, flavour, 5-alpha reductase inhibitor
Pentadecanoic acid, 14-methyl-methyl ester	Palmitic acid methyl ester	Antioxidant
Hexadecanoic acid, 15-methyl-methyl ester	Fatty acid ester	Antioxidant, nematicide, pesticide, flavour, antiandrogenic
3,7,11,15-Tetramethyl-2-hexadecen-1-ol	Terpene alcohol;	Antimicrobial
9,12,15-Octadectrienoic acid, methyl ester	Linolenic acid ester	Anti-inflammatory, insectifuge, hypocholesterolemic, cancer preventative, hepatoprotective, nematicide, antihistaminic, antieczemic, antiacne, antiandrogenic, flavour, 5-alpha reductase inhibitor, antiandrogenic, antiarthritic, anti-coronary
9,12-Octadectrienoic acid, methyl ester	Linolenic acid ester	Anti-inflammatory, insectifuge, nematicide, hypocholesterolemic, cancer preventative, hepatoprotective,   antihistaminic, antieczemic,
Oxalic acid, allyl hexadecyl ester	Dicarboxylic acid	Acaricide, antiseptic, CNS-paralytic, hemostatic, irritant, pesticide, renotoxic, varroacide

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