Increasing utilization of cowpeas to promote health and food security in

Africa

Principle Investigator

Joseph Awika, Texas A&M University, USA

Collaboratoring Scientists Susanne Talcott, Texas A&M University, USA Lloyd Rooney, Texas A&M University, USA

Bir Bahadur Singh, Texas A&M University, USA

Chitundu Kasase, University of Zambia, Zambia

John Shindano, University of Zambia, Zambia

Kalaluka Lwanga Munyinda, University of Zambia, Zambia

Kennedy Muimui, Zambia Agriculture Research Institute (ZARI), Zambia

Abdul Faraj, Prisca Tuitoek, Egerton University, Kenya

Amanda Minnaar, University of Pretoria, South Africa

Gyebi Duodu, University of Pretoria, South Africa

Abstract of Research Achievements and Impacts

Cowpea is a drought tolerant crop that has a major potential as a nutrition and food

security crop in Africa. In addition evidence indicates that legumes may contain

compounds that have health benefits against chronic diseases like cancer and

cardiovascular disease. However, large diversity in cowpea makes it difficult to

determine the varieties with the best potential to promote health. We screened 81 cowpea

lines of diverse phenotypes from around the world for phenol content and composition,

and antioxidant properties to allow for selection of lines that can be used to study health-

promoting potential of cowpea. Phenol content varied by a factor of more than 50 among

the samples analyzed (minimum 0.3, maximum 17.0 mg/g, gallic acid equivalent, GAE).

Based on seed coat color, the white varieties had the lowest phenol content (mean = 3.1

mg/g, GAE). The black, red, and light brown varieties had the highest phenol content

(means = 11.9 – 14.8 mg/g, GAE). Tannin contents also varied widely, with the lowest

values reported for the white cowpea varieties (mean = 0.59 mg/g, catechin equivalents,

CE), and the highest values in the light brown varieties (mean = 10.4 mg/g, CE).

Antioxidant activity followed the same trends as phenol content; the white cowpea

varieties had the lowest antioxidant activity (28 – 45 Umol Trolox equivalents, TE/g,

ORAC method), whereas the black, red and light brown varieties had the highest

antioxidant activity (171 – 282 Umol TE/g, ORAC method). Phenol contents correlated

significantly with antioxidant activity (R2 = 0.7 – 0.9). The antioxidants and phenols were

mostly (>97%) concentrated in the seed coat. Additionally, the trends for phenol and

antioxidant activity were consistent regardless of where the samples were grown,

suggesting that seed coat color is a major indicator of potential health benefits of cowpea.

From the screening data we have narrowed down our sample selection to the black, red

and light brown seed coat color as the ones most likely to have the best health promoting

potential. These phenotypes will be used in more advanced chemical and biochemical

studies. The selected lines will also be crossed with appropriate white cultivars to study

the genetic inheritance of seed coat color and antioxidant properties. The HC PIs and

technical personnel have been trained and are currently actively involved in generation of

data contributing to the goal of this project. Appropriate equipment were also purchased

to enable HC institutions to adequately contribute to project objectives.

Project Problem Statement and Justification Poor families in Sub Saharan Africa suffer high rates of malnutrition, especially among

children, while diet-related chronic diseases have become a common phenomenon among

urban African populations. For example, a recent survey reported that stunting and

overweight due to malnutrition coexisted and were rampant among school age children in

poor communities of Western Kenya, affecting up to 70% of the children (Abdulkadir et

al 2009). Moreover, evidence indicates that childhood malnutrition may lead to increased

risk of chronic diseases, e.g., cancer in adulthood. In fact nutrition-related chronic

diseases are becoming increasingly common in Africa, especially in urban areas, thus

putting a large strain on the limited health infrastructure and imposing economic burden

among the poor.

Research shows that regular consumption of dry beans and other legumes may reduce

serum cholesterol, improve diabetic therapy, and provide metabolic benefits that aid in

weight control (Winham and Hutchins 2007; Anderson et al 1999), as well as reduce the

risk for coronary heart disease (Bazzano et al 2001; Winham et al 2007), and cancer

(Lanza et al 2006). Thus in addition to alleviating protein malnutrition, grain pulses have

the potential to contribute to chronic disease prevention.

In Africa, malnutrition is closely linked to food insecurity, and thus the most vulnerable

groups are those in marginal rainfall rural areas, and the urban poor. Cowpea is one of the

most drought tolerant crops and has a big potential as a food security crop for many poor

African subsistence farmers. Additionally, cowpea has high quality proteins that compare

favorably with soybean proteins when substituted in diets at equivalent protein contents

(Obatuli et al. 2003; Aguirre et al 2003). A limited number of studies have also

demonstrated that cowpeas have high antioxidant capacity (Siddhuraju and Becker. 2007;

Nzaramba et al. 2005), and that the antioxidant properties may be improved by heat

processing or fermentation (Doblado et al. 2005). Recent evidence also suggests that

whole cowpea is effective at binding cholesterol and lowering blood cholesterol in

hamsters (Frota et al. (2008). However, information on how cowpea and its constituents

may directly impact human health is lacking. Additionally, how variations in cowpea

genetics affect their composition of potentially beneficial compounds is unknown. This

makes it difficult to promote cowpea as a healthy grain which dampens its demand and

utilization.

Constraints to consumption of cowpeas

The image of cowpea as a healthy food lags behind other commodities. Part of this is due

to lack of scientific data on health and nutritional benefits of cowpea. In many parts of

East and Southern Africa, the common perception that beans, cowpeas, and other pulses

are ‘poor man’s food’ has also been a major impediment to broader consumption of these

grains. Thus most of cowpea use is still restricted to the low income populations. This

leads to weak demand and depressed economic value of the crop, which in turn leads to

limited incentive to invest in efficient cowpea production and utilization infrastructure. In

the USA, lack of nutritional benefit information limits incentive to promote cowpea use

as a mainstream part of diet.

Project Rationale

Reliable scientific evidence is essential to make educated dietary recommendations on

type of cowpea, level of consumption, and design of food processing strategies that

maximize the beneficial effects. The evidence will also provide a basis for genetic and

agronomic improvement aimed at optimizing composition of beneficial compounds.

Sound scientific evidence is essential for consumer buy in. It is a first step in

transforming cowpea into a primary food to address malnutrition in poor populations, and

promoting cowpea as a mainstream part of healthy diet. This will lead to increased

demand for cowpea and improvement in economic well being of producers and overall

health of consumers.

Planned Project Activities for April 1, 2009 - September 30, 2010

Objective 1: Identify cowpea lines with high content of health enhancing compounds

and their relationship to seed color and other seed traits.

Approaches and Methods: Seeds of improved varieties and land races of cowpea

sourced from West Africa, East and Southern Africa, as well as the diverse types already

found promising in US collection were obtained and screened for bioactive compounds.

A total of 81 cowpea lines of diverse phenotypes have been screened for bioactive

composition. An additional 20 lines are being screened in Zambia and Kenya.

Gross phenolic composition. The following analyses were used for the screening: gross

phenol content, anthocyanin pigments, and tannins content. Samples were ground and

extracted in 1% HCl in methanol. Anthocyanin pigment content was measured by pH

differential method, which is based on measuring absorbance in pH 1.0 and pH 4.5

buffers at max using a scanning UV-Vis spectrophotometer, The Folin-Ciocalteu method

was used to estimate gross phenols content, by measuring reactant absorbance at 600 nm

using gallic acid as the standard. The vanillin-HCl method was used for condensed tannin

assay; reactant absorbance (with blank subtraction to correct for non tannin pigments)

was measured at 500 nm, catechin was used as standard.

To confirm location of the phenolic compounds; three representative samples were

selected and separated into seed coat and cotyledon, milled into flour and analyzed using

above methods.

From above analyses, samples were grouped into six phenotypes based on seed coat

color: black, red, light brown, brown, streaked, and white. Two representative samples

within each phenotype were selected for use in detailed chemical characterization and

biochemical assays.

Flavonoids profiling. Sample extracts obtained as described above were washed through

a C-18 column to remove sugars and other non-flavonoid constituents. Flavonoinds were

eluted using 70% acidified methanol, rotoevaporated and reconstituted in 10% methanol

containing 10 mL/L formic acid and filtered through 0.45 m membrane before analysis.

A reversed phase C-18 column was used for separation; and an Agilent 1200 HPLC

system was used for characterization.

Phenolic acid and phenolate esters. Free phenolic acids were measured in methanol

extract whereas alkaline hydrolysis of residue was used to measure esterified phenolic

acids. Reversed phase HPLC separation, with appropriate standards, was used to identify

the compounds.

Results, Achievements and Outputs of Research: The gross phenolics content of the

77 cowpea lines screened are summarized in Table 1. There was a very broad variability

in phenol content of the cowpea lines, with values ranging from 0.30 – 17 mg/g seed (dry

basis), based on the Folin-Ciocalteu method with gallic acid as the standard. This

represents more than 50 fold variability in phenol content of cowpea, which underscores

the need for a clear understanding of how the cowpea genetics and phenotypes influence

accumulation of the phenolics.

When the samples were grouped based on seed coat color, significant patterns were

observed; the white varieties generally had the lowest phenol content (0.30 – 5.5 mg/g;

mean 3.1 mg/g), with the higher value being observed in lines with a pigmented eye. The

black (mean = 14.8 mg/g), red (mean = 11.9 mg/g), and light brown (mean = 12.0 mg/g)

varieties had the highest level of phenols. The dark brown and streaked varieties had

intermediate phenol content. The results were party expected based on evidence from

other food plants; the darker seeded varieties of most plant materials usually have higher

phenol content than the non pigmented varieties. However, one unexpected observation

was that the high level of phenols in the light brown cowpea seeds, which were

comparable to the black and red varieties, and significantly higher than the dark brown

varieties. This data suggests that the types of phenols that are dominant in the light brown

phenotype do not absorb visible light. Siddhuraju and Becker (2007) also recently

observed that a light brown cowpea variety yielded extracts that contained more phenols

than a dark brown variety.

Tannins content of the cowpea lines generally followed the gross phenol content data

(Table 1). This suggests that synthesis of tannins in cowpea correlate with synthesis of

other phenolics, or that tannins contribute significantly to the phenol content of cowpeas.

The white varieties generally had very low levels of detectable tannins with an average of

0.59 mg/g (approximately 0.06%). On the other hand, the light brown cultivars had the

highest tannin content (8.8 – 12.3 mg/g).

As expected, anthocyanins were highest in the black cowpea varieties (optical density,

OD at max = 1.1), compared to the red varieties (OD at max = 0.14) and dark brown

(OD at max = 0.09). The rest of the phenotypes had trace levels of anthocyanins. The

anthocyanins likely contributed significantly to the phenol content of the black cowpea

varieties.

In investigating phenolic composition of cowpea with the goal to identify the lines with

the best potential to promote health, it is important to confirm the location of the phenols

within the seed. This would be essential when recommending processing strategies that

would limit loss of these compounds. A set of three samples were decorticated to separate

the seed coat from the cotyledon and these fractions analyzed separately. As expected,

the phenols were mostly concentrated in the seed coat (Table 2). The cotyledons

contained less that 2% of the total phenols in the cowpea. Among the major functions of

phenolic compounds in the seed is protection against pathogens and pests; thus it makes

sense that the plant would concentrate synthesis of these compounds in the seed coat.

Cereal grains are known to contain most of their phenolics in the bran layer (Awika et al

2005) More important is the implication of this information in terms of how cowpea is

processed for food in parts of Africa. In popular products like akara in West Africa, the

seed coat is typically removed, which would mean that any health benefits contributed by

the phenolics in the seed coat would be lost. As more data becomes available from this

project, we will be able to advice on appropriate ways to preserve potential health

benefits during cowpea processing.

A detailed analysis of the seed coat of selected varieties revealed that they contained

significant quantities of phenolic acids, mostly in soluble esterified and bound forms

(Table 3). The hydroxycinnamates were generally more abundant than the

hydroxybenxoates. The bound phenolic acids in the seed coats were mainly

hydroxycinnamates. The flavonoid group of phenols were more abundant than the

phenolic acids. Catechin was the most abundant flavonoid, while quercetin, naringenin,

kaempferol and rutin were also present in significant quantities. Many of these

compounds have been associated with various health benefits and it will be interesting to

discover how their levels in cowpea influence biomarkers for health.

Objective 2: Establish how the phytochemical profiles of cowpeas affect bioactivity by

measuring key markers/predictors of protection against chronic diseases

Approaches and Methods: Hydroxyl/free radical scavenging properties; protection

against oxidative stress is an important component of chronic disease prevention. Rapid

screening methods were used to determine antioxidant properties of the cowpea lines.

Antioxidant capacity of cowpeas and their fractions were measured by two widely

accepted methods that involve hydrogen atom transfer (HAT) and single electron transfer

(SET) that have been shown to correlate with biological oxidative status measures.

Oxygen radical absorbance capacity (ORAC), was the HAT method. Ability of cowpea

extract to protect fluorescein from free radical attack by AAPH was monitored for 90 min

at 37oC using a fluorescence spectrophotometer (excitation 485 nm, emission 528 nm).

The Trolox Equivalent Antioxidant Capacity (TEAC) was used for SET assay. Samples

were reacted with preformed ABTSº free radical, and ability of the sample to quench the

free radical measured after 30 min by monitoring absorbance at 734 nm. Trolox was used

as standard in both assays.

Results, Achievements and Outputs of Research: As with the gross phenolics content

there was wide variability in the antioxidant activity of the cowpea lines (Fig 1 & 2).

Antioxidant activity in the seeds ranged from 4.6 and 24.6 mol TE/g (TEAC and

ORAC methods, respectively) to 111 and 282 mol TE/g (TEAC and ORAC methods,

respectively). This represents 11 – 24 fold variation in antioxidant activity among the

cowpea cultivars. Given that antioxidant activity is broadly accepted as a major indicator

of health promoting potential of natural products and foods, this data clearly

demonstrates the importance of caution when selecting raw material for any studies

aimed at elucidating impact of legumes on health outcomes in animals and humans.

Contradictory evidence on health benefits of pulses reported in literature may be partly

attributed to the variability in phenolic composition and antioxidant activity of the raw

material used in these studies.

When the samples were grouped based on seed coat color, the white varieties once more

had the lowest antioxidant activity (5.2 – 9.6 and 28 – 45 mol TE/g, by TEAC and

ORAC methods, respectively. The light brown, red and black varieties had the highest

antioxidant activity (ranging from 69 – 111, and 171 - 282, by TEAC and ORAC

methods, respectively; the dark brown and streaked varieties had intermediate antioxidant

activity. Also, as was observed for phenol content, the antioxidant activity was

concentrated in the seed coat. The cotyledons had on average less than 3% of the

antioxidant activity observed in the cowpea seed (Table 5). This further underscores the

importance of processing method on potential health benefits of cowpeas.

Relationships between antioxidant activity and phenol content in the samples were strong

(R2 = 0.94 for TEAC versus phenol content and 0.67 for ORAC versus phenol content).

This implies that the phenolics in the cowpeas are a major contributor of the antioxidant

activity observed. Thus it is possible that determination of phenolic content of cowpea

would be a useful predictor of antioxidant properties of the cowpeas.

Significance of findings

The screening of the diverse lines of cowpea varying in seed coat color and other

properties has revealed that the composition of phenolics as well as antioxidant properties

of cowpeas vary widely, with orders of magnitudes over 50 for some attributes. This

implies that studying in vivo health properties of cowpea requires a significant level of

caution and clear characterization of the raw material to ensure that results can be

interpreted in the proper context, and also to avoid arriving at misleading inferences.

The ranking of the samples based on seed coat color was consistent for samples from

different locations, which implies that phenolic and antioxidant accumulation is

significantly influenced by genetics. Thus based on the screening results, we believe the

black, red, and light brown varieties have the best potential to produce health benefits.

Two representative lines within each of these seed coat colors have thus been selected for

detailed biochemical characterizations using human cell models. White cowpea varieties

will be used as checks in these biochemical studies. The black, red, and light brown

varieties were also selected for use in genetic trials.

Objective 3: Elucidate the mode of inheritance (heritability) of selected bioactive traits

in cowpea and genetic association between physical and bioactive traits

Approaches and Methods: Based on the results from Objectives 1&2, the following 10

varieties representing different seed colors were selected for inheritance studies:

1. IT98K-1092-1 – solid black seed coat

2. IT97K-1042-3 – solid red seed coat

3. IT82D-889 – solid red seed coat

4. IT97K-556-4 – solid brown seed coat

5. TX2028-1-3-1 – green seed coat with large black eye

6. CB-46 – white seed coat with large black eye

7. IT98K-205-8 – white seed coat with small black eye

8. GEC – white seed coat with small brown eye

9. Coronet – white seed coat with small pink eye

10. Early acre – White seed coat without eye color (eyeless)

These varieties have been planted in green house and crosses are being made using

different combinations. These are also being reanalyzed for phenols, antioxidants and

pigment composition. Efforts are being made to make sufficient types and number of

crosses to study the effect of seed coat color and eye patterns on the composition and

inheritance of different pigments and antioxidant activity.

Results, Achievements and Outputs of Research: The first planting of these parents for

crossing was done on July 26 and the second planting on Aug. 25. Based on the date of

flowering, some crosses have already been made and the process is continuing for other

crosses. The resulting F1s would be soon planted along with their parents to make

backcrosses and raise F2s for genetic studies.

Objective 4: Establish strong linkages with HC policymakers and other stakeholders,

and develop outreach strategies that will lead to long term increase in cowpea

consumption for health and food security

Approaches and Methods: HC PIs met with collaborators and representatives from

government ministries (e.g., Agriculture, Education, Public Health); and local community

based NGOs within their respective countries. The meetings were aimed to, 1) convey

project long term goal and current research plan, approaches and the rationale behind

them to stakeholders, and 2) based on expected research outputs, solicit stakeholder input

on dissemination/outreach strategies that are most likely to influence policymakers and

benefit target populations to achieve long term development impact. Each HC PI, in

conjunction with the project PI, compiled a report based on the meetings that summarizes

stakeholder suggestions.

Zambia: Through a participatory approach, a 1 day workshop was organized to which all

the identified key stakeholders were invited. In attendance was the Dean of the School of

Agriculture, University of Zambia, US PI and HC PI who gave presentations and

moderated the meeting. The collaborators were drawn from School of Agriculture and

ZARI; and key stakeholders were drawn from government ministries (Agriculture, Social

and Community Development, Health); local community and key international NGOs

(PAM, PELUM, Africare) as indicated in Table 6.

Kenya: The Kenyan stakeholders visited are detailed in Part V below.

Results, Achievements and Outputs of Research: Summary of stakeholders input from

Zambia and Kenya.

Overall: Stakeholders agreed that this project was timely and headed in the right direction

because health concerns are becoming a big demand driver in Africa. Thus the potential

to change cowpea image and demand is significant. They also agreed that this project had

a very good sustainability potential.

Specific key points

1. Need to involve stakeholders and learn from previous research experiences.

2. Must link output with strong business minded partners (business leaders) who can

see value and commercialize the output. Lack of commercialization of promising

technology has been a big problem.

3. Production goes hand in hand with utilization; i.e., do not overpromise farmers

market potential until clear demand is established. One stakeholder in Kenya

noted that we must learn from the ‘soybean experience’ when government

encouraged production but there was no ready/established market.

4. Need scientific evidence supported by facts when promoting utilization; the

evidence should be strong and compelling for easy government buy-in.

5. Involve medical doctors once data is available; people are more trusting of

doctors.

6. Develop recipes especially those that will be liked by children; this will allow

cowpea to be easily promoted through schools and youth organizations.

7. Ministry of Agriculture has a Programme that promotes ‘orphan’ crops. Cowpea

is one of the crops

8. Change locals way of thinking/attitude especially of relying on only one crop

(Maize) as a staple food

9. Develop/use of appropriate technologies e.g., using energy saving jikos, thus less

fuel for cooking

10. Proper documentation of findings is important to help policy makers

11. Talk to implementers at province and district levels

12. Go to the ground level and see what people are doing in terms of using cowpeas

13. Improve on seed delivery systems

14. Mode of preparing the cowpea for consumption; resources should be invested in

development of product variety that can appeal to not just the poor, but middle

income families as well.

15. Need to develop partnership with the stakeholder/industries to follow through

once project is completed. This could involve outcome implementation in a small

pilot area to easily demonstrate benefit.

16. Incorporate cowpea as one of the items in (i) World Food Programme packages

(ii) School feeding programme (iii) World Vision relief foods

Objective5: (Capacity Building) Strengthen cowpea nutrition research in Kenya and

Zambia

Degree Training:

PhD Student 1:

First and Other Given Names: Twambo

Last Name: Hachibamba

Citizenship: Zambia

Gender: Female

Training Institution: University of Pretoria

Supervising CRSP PI: Amanda Minnaar, Gyebi Duodu, Joseph Awika

Degree Program for training: PhD

Program Areas or Discipline: Food Science

Host Country Institution to Benefit from Training: University of Zambia

Start Date: August 2010

Projected Completion Date: June 2013

Training status (Active, completed, pending, discontinued or delayed): Active

Type of CRSP Support (full, partial or indirect) for training activity: Full

PhD Student 2:

First and Other Given Names: Alice

Last Name: Nderitu

Citizenship: Kenya

Gender: Female

Training Institution: University of Pretoria

Supervising CRSP PI: Amanda Minnaar, Gyebi, Duodu, Joseph Awika

Degree Program for training: PhD

Program Areas or Discipline: Food Science

Host Country Institution to Benefit from Training: Egerton University

Start Date: August 2010

Projected Completion Date: June 2013

Training status (Active, completed, pending, discontinued or delayed): Active

Type of CRSP Support (full, partial or indirect) for training activity: Full

PhD Student 3:

First and Other Given Names: Leonnard

Last Name: Ojwang

Citizenship: Kenya

Gender: Male

Training Institution: Texas A&M University

Supervising CRSP PI: Joseph Awika, Susanne Talcott

Degree Program for training: PhD

Program Areas or Discipline: Nutrition and Food Science

Host Country Institution to Benefit from Training: Egerton

Start Date: January 2010

Projected Completion Date: September 2012

Training status (Active, completed, pending, discontinued or delayed): Active

Type of CRSP Support (full, partial or indirect) for training activity: Partial

PhD Student 4:

First and Other Given Names: Archana

Last Name: Gawde

Gender: Female

Training Institution: Texas A&M University

Supervising CRSP PI: Joseph Awika

Degree Program for training: PhD

Program Areas or Discipline: Molecular & Environmental Plant Science

Start Date: January 2009

Projected Completion Date: September 2012

Training status (Active, completed, pending, discontinued or delayed): Active

Type of CRSP Support (full, partial or indirect) for training activity: Partial

MS Student 1:

First and Other Given Names: Billy

Last Name: Kiprop

Citizenship: Kenya

Gender: Male

Training Institution: Egerton University

Supervising CRSP PI: Abdul Faraj

Degree Program for training: MS

Program Areas or Discipline: Biochemistry

Host Country Institution to Benefit from Training: Egerton

Start Date: January 2010

Projected Completion Date: September 2011

Training status (Active, completed, pending, discontinued or delayed): Active

Type of CRSP Support (full, partial or indirect) for training activity: Partial

Short-term Training:

Type of training: Hands on laboratory techniques

Description of training activity: Hands on training on use of modern equipment and

laboratory techniques essential for the proposed project activities.

Location: University of Pretoria, Egerton University

Duration: 2 days

When did it occur: July 26 – 27, 2010; August 12, 2010

Participants/Beneficiaries of Training Activity: Chitundu Kasase (Zambia PI), Abdul

Faraj (Kenya PI), Alice Nderitu, Billy Kiprop, others

Numbers of Beneficiaries (male and female): 10 male, 7 female

PI/Collaborator responsible for this training activity: Amanda Minnaar, Gyebi Duodu,

Joseph Awika

List other funding sources that will be sought (if any): N/A

Training justification: PIs needed to familiarize themselves with the key techniques and

equipment essential for accomplishing the project objectives so they can train their

technical support staff to conduct the experiments.

Equipment (costing >$5,000):

Based on identified research capacity need by Zambian and Kenya HC project leaders,

the following equipment were acquired through Texas A&M and delivered to the HC

institutions.

Equipment 1

Specific Type of Equipment to be purchased:

Fluorescence/luminescence plate readers, with fluid delivery system

Justification for equipment to achieve workplan objectives:

University of Zambia, Zambia, requested the fluorescence plate reader that will be

essential for the free radical and related biochemical assays proposed. The data obtained

from this instrument will complement data from Kenya and South Africa. This

instrument is also very versatile and can be used to analyze DNA/RNA, cellular

toxicology, cell proliferation and various health-related biological assays. We expect that

as their human resource capability expands, University of Zambia researchers will be

able to fully take advantage of the instrument.

Institution benefitting from equipment: University of Zambia

Amount spent on equipment by TAMU: ~ $16,000 (including shipping cost)

Equipment 2

Specific Type of Equipment to be purchased:

True dual beam scanning UV-Vis spectrophotometers

Justification for equipment to achieve workplan objectives:

Egerton University requested a modern UV-Vis spectrophotometers to be able to perform

proposed phytochemical and biochemical characterization of cowpeas and related

analyses. The instrument will allow Egerton University to produce data that is

complementary to that from University of Zambia, and thus will enhance collaboration

between the HC institutions.

Institution benefitting from equipment: Egerton University, Kenya

Amount spent on equipment by TAMU: $12,000 (including shipping cost)

Networking and Linkages with Stakeholders During the Planning Meeting and Training Workshop held in Pretoria, South Africa from

26-29 July 2010. US PI and HC PI’s met with Ms. Cecilia M Khupe, Senior Regional

Agriculture Programme Manager from USAID Southern Africa to introduce the new

CRSP project and HC PI’s to the Mission.

USAID Zambia: the US PI and Zambia HC PI met with Mr Mlotha Damaseke,

Agriculture and Natural Resources and Mission Environmental Officer, at the USAID

mission in Lusaka. He was very enthusiastic about the project goals and promised to be

supportive.

Other field/stakeholder visits:

Zambia: Meetings/visits were organized by HC PI, and attended by both HC and US PI

1. SADC Plant genetic Resources center – Thandie Lupupa (Senior Program Manager)

2. National Genetic Resource Center, ZARI – Mr Phiri

3. Golden valley Research Trust (GART) – Mr Simunji (Technical officer)

4. National Food and Nutrition Commission – Dr Cassim Masi ( Executive Director)

5. Program Against malnutrition (PAM) – Dr Kayoya Masuhwa ( Executive Director)

6. Africare - Frank P Chisamanga (Market Improvement and innovation facility

Cordinator)

7. Participatory ecological land use management (PELUM) – Ms Faustina Chipalo –

V/Board chairperson).

8. National Institute for Scientific and Industrial research (NISIR) – Mr Luke Mugode

(Scientific Officer, Postharvest food processing and nutrition program)

9. National Plant protection Office, ZARI – Mr Ken Msiska (Technical Officer)

10. Ministry of Agriculture and Cooperatives(MACO) – Mr Aaron Simwanza

11. Ministry of Community Development and Social Services (MCDS) – Mr Siansimbi

(Food Security Pack Coordinator)

Kenya: Meetings/visits were organized by HC PI, and attended by both HC and US PI

1. Head of Home Economics (Veronica Kirogo), Ministry of Agriculture HQ NBI

2. Chief Nutritionist (Rosemary Ngaruro), Ministry of Medical Servives HQ NBI

3. Head, Nutrition Division (Terry Wefwafwa), Ministry of Public Health and Sanitation

HQ NBI

4. Legume Breeder (David Macharia) KARI Katumani

5. Simlaw Seeds Co. Ltd, a subsidiary of Kenya Seed Company (Robert Musyoki-

Research officer-NBI)

6. World Vision (Haron Chesaina) Marigat District

7. Ministry of Agriculture Marigat District- Extension section (Benjamin Chemjor)

8. Agronomist (Timon Moi) KARI – Pekerra

9. Food Biochemist (John Ndungu) – KARI – Njoro.

Tables/Figures Cited in the Report

Table 1: Phenol and tannin content of cowpea varieties grouped by seed coat color.

Seed coat color Gross phenol content (mg/g,

db)

Condensed tannin content (mg/g,

db)

N

Range Mean Range Mean

White 0.30 – 5.5 3.1 a 0.29 – 1.3 0.59 a 36

Light brown 5.7 – 16.5 12.0 c 8.8 – 12.3 10.4 d 21

Dark brown 5.2 – 9.0 6.8 b 1.9 – 6.7 3.6 b 8

Streaked 5.4 – 9.9 8.5 b 3.6 – 3.8 3.7 b 5

Red 10.1 – 14.2 11.9 c 4.8 – 7.8 7.3 c 5

Black 12.5 – 17.0 14.8 cd 6.3 - 9.0 7.7 c 3

N represents the number of varieties analyzed within a phenotype. Coefficient of variability for phenol

content determination was 3.1% and for condensed tannins was 4.4%. Values with same letters in a column

are not significantly different (p < 0.05).

Table 2: Phenolic content (g/100 g (dry weight basis) of extracts prepared from cowpea seed coats and

cotyledons with acidified dimethyl formamide (DMF) and acidified methanol1

Variety Solvent used

Glenda

Mae a tsilwane

Mogwe o kgotsheng

Glenda

Mae a tsilwane

Mogwe o kgotsheng

Acidified DMF

Seed coat

25.85 d2 (0.17)

3

33.41 e (0.41)

37.70 f (0.17)

Cotyledon

0.57 d (0.01)

0.41 c (0.01)

0.39 c (0.01)

Acidified methanol

Seed coat

13.46 a (0.01)

18.16 b (0.13)

21.84 c (0.01)

Cotyledon

0.29 b (0.02)

0.09 a (0.01)

0.08 a (0.02) 1Results are means of four determinations, on dry weight basis

2 Mean values for seed coats and cotyledons in each row and column with the same letter are not

significantly different at (p < 0.01) 3 Standard deviation values are given in parentheses

Table 3: Levels of phenolic acids and flavonoids (mg/kg sample on dry basis) in free, soluble-esterified and bound fractions from seed coats of

Mae a tsilwane and Mogwe o kgotsheng cowpea varieties

Phenolic compound Mae a tsilwane Mogwe o kgotsheng

Free Soluble

esterified

Bound Free Soluble

esterified

Bound

Hydroxybenzoates

Gallic acid

Protocatechuic acid

p-Hydroxybenzoic acid

Vanillic acid

Syringic acid

Hydroxycinnamates Caffeic acid

p-Coumaric acid

Sinapic acid

Ferulic acid

Cinnamic acid

Flavonoids Catechin

Rutin

Naringin

Myricetin

Quercetin

Naringenin

Kaempferol

Hesperetin

30.6 ab1 (1.5)

2

37.3 a (6.0)

ND3

45.0 c (10.8)

18.7 a (7.8)

63.5 ab (5.2)

26.8 a (0.8)

38.3 a (5.4)

6.2 a (0.7)

17.6 b (0.6)

919.7 b (21.5)

22.0 ab (4.4)

25.2 c (3.5)

ND

56.1 e (6.3)

6.2 b (0.7)

29.2 abc (3.4)

ND

30.5 ab (0.1)

97.7 c (0.2)

1.9 a (0.1)

28.2 ab (0.2)

ND

70.1 b (0.6)

31.9 ab (0.1)

35.5 a (0.9)

14.8 b (0.1)

16.6 ab (0.1)

467.7 a (12.4)

27.4 b (0.3)

14.1 a (0.4)

84.0 a (6.3)

32.0 ab (0.1)

ND

27.3 ab (0.1)

ND

41.8 d (0.1)

436.2 e (27.1)

ND

29.8 ab (1.6)

ND

81.5 c (2.4)

83.8 e (10.8)

37.7 a (6.2)

92.2 f (4.1)

47.5 d (0.9)

2838.2 e (19.7)

ND

40.0 d (2.2)

ND

ND

ND

31.5 cd (1.0)

ND

31.3 b (0.1)

53.4 ab (0.9)

ND

34.9 ab (1.1)

ND

106.9 d (13.5)

26.9 a (1.5)

29.0 a (0.1)

7.0 a (0.1)

16.6 ab (0.2)

1645.4d (48.9)

27.4 b (0.8)

20.6 bc (0.1)

80.8 a (1.5)

33.1 ab (0.2)

0.9 a (0.2)

28.4 abc (0.6)

ND

28.2 a (0.1)

149.4 d (19.5)

ND

26.7 a (1.0)

14.6 a (0.5)

54.1 a (0.2)

41.2 c (3.3)

129.6 c (17.5)

20.9 bc (1.5)

16.3 ab (0.2)

498.1 a (62.0)

17.8 a (2.2)

15.4 a (0.8)

ND

31.3 a (0.1)

ND

26.5 a (0.1)

ND

36.7 c (2.9)

93.0 c (11.1)

2.3 a (1.5)

26.9 a (0.1)

14.9 a (2.3)

70.7 bc (0.1)

51.9 d (0.8)

23.1 a (15.7)

54.1 d (5.5)

16.0 a (0.1)

1323.7 c (8.0)

58.9 d (1.6)

17.7 ab (2.6)

804.7 c (77.4)

39.1 cd (0.2)

ND

30.5 bc (0.5)

ND

1Mean values with different letters across the row are significantly different (p < 0.05)

2Standard deviations in parentheses

3ND – not detected

Table 4. Cowpea line Identification (for Fig 1&2)

Sample No. Variety Seed coat color

1 09FCV-E IT99K-407-8 Light brown

2 09FCV-M-UCR 799 Light brown, pink

3 09FCV-M-IT97K-556-6 Light brown, pinkish

4 09FCV-E YACINE Light brown (golden)

5 09FCV-E IT85M-303 White, brown patches

6 09FCV-M-UCR 5272 Red

7 09FCV-E IT85F-867-5 Red, brownish

8 09FCV-E IT95K-1105-5 Black

9 IT99k-216-48-1 Black

10 09FCV-M FVX421-25 dark brown (golden)

11 09FCV-M-IT93K-693-2 dark brown (golden)

12 09FCV-M-UCR 1432 Chocolate brown

13 09FCV-M MOUNGE Streaked

14 09FCV-E 5248 White, black eye

15 09FCV-E-BAMBEY 21 White, no eye

16 09FCV-E-IT95M-190 White, brown eye

17 09FCV-E-IT95K-1491 White, black eye, greenish

Table 5: Antioxidant (free radical scavenging) activity (TEAC)

1 of extracts prepared from cowpea seed coats and

cotyledons with acidified dimethyl formamide (DMF) and acidified methanol2

Variety Solvent

Glenda

Mae a tsilwane

Mogwe o kgotsheng

Glenda

Mae a tsilwane

Mogwe o kgotsheng

Acidified DMF

Seed coat

2470 d3 (39)

4

3053 e (30)

3385 f (60)

Cotyledon

50 d (1)

46 c (1)

44 c (1)

Acidified methanol

Seed coat

1187 a (44)

1625 b (32)

1796 c (11)

Cotyledon

36 b (1)

24 a (1)

23 a (1) 1(M Trolox Equivalent (TE)/ g)

2Results are means of four determinations, on dry weight basis

3Mean values for seed coats and cotyledons in each row and column with the same letter are not significantly

different at (p < 0.01) 4 Standard deviation values are given in parentheses

Table 6. List of Participants. Stakeholders meeting workshop. Golfview hotel, Lusaka, Zambia, 4th

August 2010.

NAME INSTITUTION ADDRESS

CASSIM

MASI

NFNC BOX 32669, Lusaka

JUDITH LUNGU UNZA 32379,Lusaka

HENRY NKHOMA MCDSS P/B W252, Lusaka

JOSEPH AWIKA TEXAS A&M 2474 TAMU

HIMOONGA.B.MOONGA UNZA BOX 32379

KENNEDY K. MUIMUI ZARI-KASAMA BOX 410055, Kasama

FRANK P. CHISAMANGA AFRICARE/MIIF BOX 3392

Lusaka

MUSONDA MOFU NFNC BOX 32669, Lusaka

FAUSTINA MWENDA PELUM ZAMBIA BOX 30443, Lusaka

AARON SIMWANZA MACO BOX 50291

KAYOYA MASUHWA PAM

KALALUKA MUNYINDA UNZA BOX 32379, Lusaka

MOSES BANDA UNZA BOX 32379, Lusaka

CHITUNDU KASASE UNZA BOX 32379, Lusaka

Fig 1. Antioxidant activity of 16 representative cowpea lines measured by the oxygen radical absorbance

capacity (ORAC) method (values are on dry basis). Error bars are ±sd [see table 4 for sample

identification]

Fig 2. Antioxidant activity of 16 representative cowpea lines measured by the trolox equivalent antioxidant

capacity (TEAC) method (values are on dry basis). Error bars are ±sd. (See table 4 for sample

identification)

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FY 2011 SEMI-ANNUAL INDICATORS OF PROGRESS BY INSTITUTIONS AND TIME PERIOD

Project Title: Increasing utilization of cowpeas to promote health and food security in Africa

Abbreviated name of institutions

Identify Benchmark Indicators by Objectives

TAMU UNZA EGER UP

4/1/11

9/30/11

4/1/11

9/30/11

4/1/11

9/30/11

4/1/11

9/30/11

4/1/11

9/30/11

4/1/11

9/30/11

Objective 1 Phytates X

Protein content X

Protein quality and digestibility X X

Screening backcrosses:

Phenolic tests X

SET and HAT X

Objective 2 Bile acid binding

assay X X

Inhibition of LDL oxidation X X

Glycemic Index X X

Phase II X X

Anti-proliferation x

Biomarkers for inflammation X X

Antioxidant biomarkers x

Objective 3 Perform relevant

crosses x x

Obtain F3 seed x x

Conduct field trials x x x x

Objective 4 HC stakeholder

workshops x x x

Graduate training (PhD) x x x x

Name of the PI responsible for reporting on benchmarks J Awika C Kasase A Faraj A Minnaar

Signature/Initials:

Date:

FY 2011 PERFORMANCE INDICATORS

for Foreign Assistance Framework and the Initiative to End Hunger in Africa (IEHA)

Project Title: Increasing utilization of cowpeas to promote health and food security in Africa

Lead U.S. PI and University: Joseph Awika, Texas A&M University Host Country(s): Zambia, Kenya

2011 Target 2011 Actual

Output Indicators (October 1, 2010-Sept 30,

2011)

Degree Training: Number of individuals enrolled in degree training

Number of women 2

Number of men 1

Short-term Training: Number of individuals who received short-term training

Number of women 15

Number of men 15

Technologies and Policies

Number of technologies and management practices under research 4

Number of technologies and management practices under field testing 1

Number of technologies and management practices made available for transfer 0

Number of policy studies undertaken 0

Beneficiaries:

Number of rural households benefiting directly 0

Number of agricultural firms/enterprises benefiting 0

Number of producer and/or community-based organizations receiving technical assistance

Number of women organizations receiving technical assistance

Number of HC partner organizations/institutions benefiting 3

Developmental outcomes:

Number of additional hectares under improved technologies or management practices 0