Agronomic Research in Mali Identifies Local Sources of Micronutrients
New results from research into the micronutrient content of
local plant species in Mali have shown that applying very
simple measures may enhance nutrient bio-availability. Over
the last three years, Malian agroforesters, in collaboration with
the Novartis Foundation and Roche's Sight and Life Task
Force, have discovered that the simple practice of drying
baobab leaves in the shade doubles the pro-vitamin A content
of the baobab powder. Furthermore, the choice of small
leaves (which is tree specific) also increases pro-vitamin A
levels by 20%. The combination of small leaves and shadedrying
result in a pro-vitamin A content of up to 27mg retinol
equivalents (RE) per gram of dried leaf powder, a very high
level (see graph; reference 1). These results are particularly
important for a country such as Mali, classified as having
‘clinical’ or severe vitamin A deficiency by WHO (1995)1, and
where few vitamin A-rich foods are consumed on a regular
basis. An exception to this are locally gathered baobab
leaves, which are typically sun-dried, pounded into powder,
and cooked in the daily family sauce.
Malian agroforesters and collaborators from the Novartis Foundation
and Roche's Task Force Sight and Life, have also
discovered a remarkable tree-to-tree variability in vitamin C
content in the fruit of baobab trees (2). This variation ranges
from 150 to 500mg vitamin C per 100g fruit and remains stable
from one year to the next. Baobab fruit pulp is known to be rich
in vitamin C, and across West Africa baobab fruit pulp is
consumed in cool drinks and warm gruels. It has also recently
become a popular ingredient in iced products in urban areas.
Researchers have grafted branches from trees with a high
content (500 mg/100g) of vitamin C onto over 100 young
baobab trees at the Cinzana Research Station in the Ségou
region of Mali. It is hoped that this ‘vitamin C’ orchard may
serve as important graft stock for Sahelian vitamin C orchards
in the future (3).
Both iron and zinc are lacking in foods eaten by Malian
children. Although the mineral content has been characterised
for many trees and plants in Mali (4), little is known about the
genetic variability of the mineral content within different
species. To this end, an iron and zinc survey of Zizyphus
mauritania fruits, and of Amaranthus viridis (borronboulou) and
Adansonia digitata (baobab) leaves is planned for the 1999
season. Plant materials will be gathered from a large number
of individual plants sampled from several diverse agroecological
zones. In order to respect full comparability of results, the
analyses will be carried out at Waite Analytical Services in
Adelaide, Austrailia.
Graph: Baobab leaf content of pro-vitamin A carotenoids as retinol equivalents (RE)
Lessons Learned
Experience in the measurement of nutrients from local plant
species has brought to light three findings worth sharing with
others seeking to undertake similar efforts:
1. Genetic diversity. The reporting of mean values of numerous
samples, or the values of bulked samples, can mask the
enormous diversity that may exist between individual plants. In
the Malian studies, the baobab fruit measurements of bulked
samples from many trees consistently resulted in vitamin C
values of around 220 mg/100g. It was only when researchers
measured bulked fruit from individual trees that a threefold
range of values from 150 to 500mg/100g vitamin C was
discovered.
2. Distinguishing between sun and shade drying. Pro-vitamin A
is very sensitive to sunlight. With baobab leaves, it was found
that shade drying can double the RE values compared to sun
drying, even though sun drying is the common local practice. It
is important to at least report how plant samples are dried, and
where possible, to compare pro-vitamin A or RE values from
sun-dried versus shade-dried plant samples.
3. Beware of market samples. We have measured many
market samples of baobab leaves and fruits. b-carotene and
vitamin C levels were far inferior to any samples that were
gathered directly from trees. We have been repeatedly told
that market samples are commonly extended with innocuous
material such as cereal stalk pulp. However, in the literature,
nutrient levels are commonly reported from plant samples
obtained in local markets rather than directly from original plant
sources.
The Baobab Tree
J Scheuring
Since 1979, the Malian agronomic research institute (IER),
through the continued support of the Novartis Foundation for
Sustainable Development, has been addressing various aspects
of child nutrition through agronomics, grain storage
technology, food technology, and agroforestry. Locally available
technologies have been developed to enrich the amino
acid quality of millet foods with cowpea, to increase caloric
density of infant gruels with malt, and most recently - as
described in this article - to obtain high levels of vitamin A and
C from baobab leaves and fruit. It is now time to put all this
research into action. In 1999, village-level feeding programmes
are planned. These will combine increased caloric density and
protein quality in children’s foods, as well as increase intake of
vitamins A and C from Baobab sources. This work will involve
the active inputs from agronomists, nutritionists, and anthropologists.
Nutrition Activities in Micronesia
The Federated States of Micronesia (FSM) is located in the
North Pacific and is made up of four states - Pohnpei, Chuuk,
Kosrae, and Yap. Evolving from the U.S. Trust Territories,
FSM became a new nation in 1986. The population is
estimated at 111,000. Difficulties involved in nutrition programmes
there, include the dispersed location of the four
island states, the eight different languages, different cultures,
as well as changes in the diet that have evolved in recent
years. However, some exciting progress has been made,
including projects supported by UNICEF, in conjunction with
the FSM Department of Health, Education and Social Affairs.
Baby Friendly Hospital Initiative (BFHI)
The smallest state of Kosrae is preparing for external assessment
for Baby-Friendly status. Its Breastfeeding Mothers Support
Group, has been described as “the first of its kind in the
Pacific” by the regional UNICEF breastfeeding officer, because
of the group’s enthusiasm and determination to reach every
mother on the island. In Kosrae’s internal BFHI assessment,
it was revealed that the local hospital was denying the group
the right to enter the delivery room for assistance to mothers.
The Hospital Chief of Staff admitted that he had not realised
how important the group was, and the hospital regulations
were changed. New badges for the support group mothers
provide identification, and the group will now be able to
provide support to mothers. Chuuk and Pohnpei are also
actively preparing for Baby Friendly status, and the National
Congress is considering the first FSM legislation on | 
