Featured Research

from universities, journals, and other organizations

Using cassava to address vitamin A deficiency

Date:
January 7, 2011
Source:
American Society of Plant Biologists
Summary:
Cassava is an important food source in many poverty-stricken regions of the world, including sub-Saharan Africa, but the low levels of micronutrients in commercial varieties do little to address hidden hunger. New research shows that a single, naturally arising change in one gene leads to high provitamin A levels in cassava roots and opens the door to addressing vitamin A deficiency via biofortified cassava.

White cassava roots (top) are low in micronutrients, whereas yellow-rooted plants can have twenty times as much provitamin A.
Credit: International Center for Tropical Agriculture (CIAT)

The roots of cassava (Manihot esculenta) serve as the primary source of carbohydrates in the diets of people in many arid regions of the world, including more than 250 million people in sub-Saharan Africa. Unfortunately the roots of commercial cassava cultivars are quite low in micronutrients, and micronutrient deficiencies are widespread in these regions. In addition to programs designed to deliver vitamin supplements, there has been considerable effort aimed at biofortification; that is, increasing the amounts of available micronutrients in staple crops such as cassava.

Related Articles


An article published in The Plant Cell this week describes the results of a collaborative effort led by Professor Peter Beyer from Freiberg University in Germany, together with researchers at the International Center for Tropical Agriculture (CIAT) in Colombia. These researchers studied a naturally arising variant of cassava with yellow roots in order to understand the synthesis of provitamin A carotenoids, dietary precursors of vitamin A. Beyer was also co-creator of Golden Rice, a biofortified crop which provides precursors of vitamin A not usually present in the rice that people eat.

In this work, the scientists compared different cassava cultivars with white, cream, or yellow roots -- more yellow corresponding to more carotenoids -- in order to determine the underlying causes of the higher carotenoid levels found in the rare yellow-rooted cassava cultivar. They tracked the difference down to a single amino acid change in the enzyme phytoene synthase, which functions in the biochemical pathway that produces carotenoids. The authors went on to show that the analogous change in phytoene synthases from other species also results in increased carotenoid synthesis, suggesting that the research could have relevance to a number of different crop plants. Furthermore, they were able to turn a white-rooted cassava cultivar into a yellow-rooted plant that accumulates beta-carotene (provitamin A) using a transgenic approach that increased the enzyme phytoene synthase in the root.

This work beautifully combines genetics with biochemistry and molecular biology to deepen our understanding of carotenoid biosynthesis. "It paves the way for using transgenic or conventional breeding methods to generate commercial cassava cultivars containing high levels of provitamin A carotenoids, by the exchange of a single amino acid already present in cassava" says Beyer. Thus, it has the potential be a big step the battle against vitamin A deficiency, which is estimated to affect approximately one third of the world's preschool age children.

This research was supported by the HarvestPlus research consortium, which received a grant from the Bill & Melinda Gates Foundation.


Story Source:

The above story is based on materials provided by American Society of Plant Biologists. Note: Materials may be edited for content and length.


Journal Reference:

  1. R. Welsch, J. Arango, C. Bar, B. Salazar, S. Al-Babili, J. Beltran, P. Chavarriaga, H. Ceballos, J. Tohme, P. Beyer. Provitamin A Accumulation in Cassava (Manihot esculenta) Roots Driven by a Single Nucleotide Polymorphism in a Phytoene Synthase Gene. THE PLANT CELL ONLINE, 2010; DOI: 10.1105/tpc.110.077560

Cite This Page:

American Society of Plant Biologists. "Using cassava to address vitamin A deficiency." ScienceDaily. ScienceDaily, 7 January 2011. <www.sciencedaily.com/releases/2010/10/101004130109.htm>.
American Society of Plant Biologists. (2011, January 7). Using cassava to address vitamin A deficiency. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2010/10/101004130109.htm
American Society of Plant Biologists. "Using cassava to address vitamin A deficiency." ScienceDaily. www.sciencedaily.com/releases/2010/10/101004130109.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) — The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) — Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) — Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Are Female Bosses More Likely To Be Depressed?

Are Female Bosses More Likely To Be Depressed?

Newsy (Nov. 24, 2014) — A new study links greater authority with increased depressive symptoms among women in the workplace. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins