Pittosporum resiniferum Hemsl.
Petroleum nut (English) Hanga (Philippine)
Source: James A. Duke. 1983. Handbook of Energy Crops. unpublished.
- Folk Medicine
- Yields and Economics
- Biotic Factors
Called petroleum nut because of the fancied resemblance of the odor of the
fruit's oil to that of petroleum, the fruits, even green ones, burn brilliantly
when ignited. Hence they are used like torch nuts or candlenuts for
illumination in the bush. Dihydroterpene (C10H18) is used in perfumes and
medicines. Heptane (C7H16) is a component of gasoline, and has been suggested
as a possible component of paint and varnish (Anonymous, 1981c).
Fruit is used as a panacea by Philippine traditionalists, especially, however,
for abdominal pain. The oleoresin is used to treat muscular pains and skin
diseases (Perry, 1980). The nut decoction is used for colds. Crushed nuts are
mixed with coconut oil as a relief for myalgia. Altschul (1973) quotes from a
1947 Sulit herbarium specimen, "Petroleum gas extracted from the fruit is
medicinal for stomachache and cicitrizant."
The volatile oil of the fruit is reported to contain "dihydroterpene and
heptane, which is a cardiac glycoside." (Perry, 1980). The Horticultural and
Special Crops Laboratory at Peoria analyzed an accession of fruit, and
identified, from its "squeezings", constituents passing through a gas
chromatographic column, heptane (about 45% of the elutents) nonane,
a-pinene or b-ocimene, b-pinene, myrcene, and unidentified materials.
According to Nemethy and Calvin (1982) the essential oil (8-10% of fruit
weight) contains myrcene (40%) and a-pinene (38%) in ± equal quantities
(P. undulatum's contains mostly limonene). The two components n-heptane
(5%) and n-nonane (7%) are minor components.
Aromatic tree to 30 m tall, but probably smaller in its elfin forest habitat
(perhaps even epiphytic); fruiting when only 612 m tall. Leaves aromatic,
coriaceous, entire (possibly evergreen), thickest above the middle, pinnately
nerved, with a short acumen at the tip. Flowers fragrant, white, clustered on
the stems. Fruits average 25 mm in diameter (1243). Each fruit has 572
seeds (average 31), the seeds ranging from 140 mm, averaging 3 mm. The seeds
are about as close to hexahedral and prismatic as any I have seen, being quite
angular, black to blackish gold, often still surrounded by a gummy or resinous
The FORI Director in the Philippines is actively collecting superior germplasm
in the high mountains of Bontoc and Benguet where they abound, especially in
elfin forests.(2n = 24)
In the Philippines, petroleum nut is locally known in Benguet as apisang,
abkol, abkel, and langis; in the Mountain Province, dael and dingo, and in
Abra, sagaga. It abounds in Mt. Pulis, Ifugao, and is reported from the
headwaters of the Agno and Chico River Basins. Also in the Bicol Provinces,
Palawan, Hindoro, Nueva Ecija, and Laguna Provinces. It is being cultivated at
FORI's Conifer Research Center, Baguio City.
Petroleum nut is reported to range from 6002,400 m elevation, usually in elfin
or Benguet Pine Forest. Average of 7 climatic data sites where the
Pittosporum grows, was close to 1,000 m, the range from ca 550 to 2,000
m. Whether or not it can stand frost, dry heat, and drought is questionable.
Frequently, species of elfin forests have very narrow ecological amplitudes and
do not thrive in other vegetation types. Results of transplants and trials are
unavailable to me now. Reportedly seed were introduced once, at least to
Hawaii. Thanks to Professors Ludivina S. de Padua, S.C. Hales, and Juan V.
Pancho of the Philippines, we now have a fairly good idea of the ecosystematic
amplitudes of the Pittosporum, an energy plant that has captured the
imagination of many. Professor de Padua checked off all the climatic data
points (from our climatic data base) at which Pittosporum resiniferum was growing, prior to its widespread introduction for
potential energy studies elsewhere in the Philippines. Ranging from Tropical
Dry to Moist through Subtropical Forest Life Zones, the petroleum nut grows
where the annual precipitation ranges from 15 to more than 50 dm (mean of 36
cases = 27 dm), annual temperature from 1828°C (mean of 17 cases =
26°C). Of 17 cases where both temperature and rainfall data were available
to us, 13 would suggest Tropical Moist Forest Life Zone, three would suggest
Tropical Dry, and one would suggest Subtropical Rain Forest Life Zones.
Seeds and cutting can be used to propagate the tree. Seeds may lose their
vitality rather rapidly. According to Juan V. Pancho (personal communication,
1982), "from my experience, the seed lost its viability after one month
Currently, seeds are harvested from the wild.
A single fruit yields 0.13.3 ml, averaging about 1.3 ml. In general, the
bigger the fruit, the larger the seed, and the greater the oil content
(Veracion and Costales, 1981). It is reported (Anonymous, 1981) that a single
tree from Mount Mariveles, Bataan, yielded 15 kg green fruits, which yielded 80
cm3 of oil. The residue, ground up and distilled with steam,
yielded 73 cm3 more. Another report gave 68 g per kg fresh nuts,
suggesting about 1 kg oil per tree yielding 15 kg (Anonymous, 1981c).
Currently seed are being sold at $2.00 per gram in 5-gram lots (ca 40 seed per
g) by the FORI Seed Officer, Forest Research Institute, College, Laguna,
The plant was discovered as a hydrocarbon source just after 1900, but based on
the previous paragraph, it seems it would take 1,000 trees per ha to get one MT
oil per hectare from the fruits. Perhaps the resin in the leaves, twigs, etc.
would equal or exceed this; figures are not yet available. The oil derived
from the fruits is quite sticky and rapidly turns resinous when laid thin. In
an open dish, it burns strongly, although with a sooty flame (Anonymous, 1981).
C.A. Arroyo (1981) notes that for home use as fuel, "the husk of African oil
palm nuts could be much better than the petroleum nut that emits sooty smoke
and strong smell." Recently, I heard rumors that President Marcos was
encouraging each Philippine farmer to plant five trees in the hopes that they
could obtain 300 liters of oil therefrom, per year. I saw nothing about this
at the Philippine exhibit at the World's Fair in June 1982. However, if yields
of 60 liters of oil per tree are possible, the tree should certainly be
examined! In the January 1981 issue of Canopy, Generalao (1981) lists petroleum
nut at the top of a long list of potential oil seeds including Pongamia
pinnata, Sterculia foetida, Terminalia catappa, Sindora supa, Calophyllum
inophyllum, Canarium luzonicum, Aleurites moluccana, Aleurites trisperma,
Mallotus philippensis, Barringtonia asiatica, Sindora inermis, Pithecellobium
dulce, Tamarindus indica, Chisocheton cumingianus, Jatropha curcas, and
Euphorbia philippensis to help the Philippines solve their energy
problem (importing 85%). Presidential Decree 1068 declares the imperative
acceleration of research on energy alternatives. Speaking in that same issue
of Canopy, an editorial notes that in 1978 FORI concluded the flammable element
in petroleum nut is volatile, evaporating quickly like acetone. Some chemists
believe admixing another element will stabilize the compound. One seed catalog
(Anonymous, ca 1983) has very optimistic notes about the plant. "The Gasoline
Tree produces masses of apricot-sized orange fruits which when cut and touched
with a match leap into flame and burn steadily. The fruits contain 46% of
gasoline type components (heptane,dihydroterpene, etc.), which are found in
extensive networks of large resin canals. If planted the estimated yield would
be about 45 tons of fruit or 2500 gallons of 'gasoline' per acre per year."
No data available.
Complete list of references for Duke, Handbook of Energy Crops
- Altschul, S. von R. 1973. Drugs and foods from little-known plants. Harvard
Univ. Press. Cambridge, Mass. 366 p.
- Anon. 1981c. Here comes (again). Canopy International 7(1):6.
- Anon. ca 1983. Hurov's tropical seeds. Catalog 34.
- Arroyo, C.A. 1981. Fuel for home use. Canopy International. 7(7):15.
- Generalao, M.L. 1981. Those seemingly insignificant plants. Canopy
- Perry, L.M. 1980. Medicinal plants of east and southeast Asia. MIT Press,
- Veracion, V.P. and Costales, E.F. 1981, The bigger, the more. Canopy Int.
Last update Wednesday, January 7, 1998 by aw