About

Professor Raymond Glahn is associated with the Bronfenbrenner Center for Translational Research at Cornell University. The center assists faculty in developing translational research projects by providing support such as proposal preparation assistance, training, technical support, and help in brokering collaborative relationships. The center also offers workshops, an intensive summer institute, and talks on current research to facilitate the dissemination and application of research findings. While specific details about Professor Glahn's individual research focus or background are not provided on the page, his affiliation with the center indicates involvement in translational research efforts aimed at applying scientific knowledge to real-world issues.

Research topics

• Horticulture
• Biology
• Chemistry
• Food science
• Animal science
• Geography
• Agronomy
• Biochemistry

Selected publications

• Enhancing the Iron Nutrition of Beans: Utilizing the Slow and Non-Darkening Traits to Reduce Proanthocyanidins in Multiple Market Classes of Dry Beans

  Current Developments in Nutrition · 2024 · 3 citations

  1st authorCorresponding
  • Food science
  • Chemistry
  • Horticulture

  Objectives: Reducing proanthocyanidin concentrations (inhibitors of iron absorption) in bean seed coats via alleles in the non-darkening (j gene) or slow darkening (Psd) gene will enhance iron (Fe) bioavailability across multiple market (color) classes of dry beans. Methods: Dry beans (Phaseolus vulgaris L.) with slow-darkening (SD), non-darkening (ND), and regular darkening (RD) traits were grown at research sites in North America (U.S. and Canada) and Africa (Zambia). The Caco-2 cell culture bioassay was used to determine the iron bioavailability of cooked beans. Mineral analysis was conducted by ICP-ES and phytate measured with a Megazyme™ kit. Flavonoids ( >25 compounds) were measured using a newly developed Acetone-Methanol (acidified) extraction methodology before analysis with UPLC/MS. Results: SD pinto beans from North Dakota provide 2-7x more bioavailable iron than RD pinto varieties. Iron and phytate concentrations were similar between SD and RD pinto beans, however, flavonoid analysis revealed 4x more proanthocyanidins were detected in RD pintos after cooking. Similar findings were demonstrated in ND yellow, cranberry and purple beans produced in North America and Africa. The absence or low levels of proanthocyanidins in the seed coats of ND beans correlated with 5-7x more bioavailable iron than RD beans. The greatest enhancement was observed in the yellow bean market class with a ND variety exhibiting 200% of a white kidney bean reference control. There was no relationship between iron bioavailability, phytate or iron concentrations in cooked beans. However, there was a strong (P < 0.001) association between iron bioavailability and proathocyanidins across all market classes. Conclusions: In addition to a brighter seed coat appearance after storage, this study reveals that downregulating the synthesis of proanthocyanidins with the slow darkening (Psd) or non-darkening (j) gene could be a novel, as well as a sustainable strategy to improve the iron bioavailability of dry beans, especially those susceptible to darkening, including yellow, pinto, purple and cranberry beans. Funding Sources: U.S. Department of Agriculture, Agricultural Research Service.

  DOI

• On-Farm Evaluation in Uganda of Iron Concentration and Iron Bioavailability in the Fast Cooking Manteca Yellow Bean (Phaseolus vulgaris L.).

  Current Developments in Nutrition · 2020 · 1 citations

  1st authorCorresponding
  • Chemistry
  • Food science
  • Animal science

  To evaluate the genotype by environment (GxE) influence on Fe concentration and Fe bioavailability of select fast cooking bean varieties in Uganda. This study compared two fast cooking Manteca genotypes (Ervilha, Cebo) to eight other white, yellow and red mottled genotypes, which included farmer local check varieties NABE15 and Masindi yellow. Genotypes were produced as a group across nine on-farm locations in Uganda over two field seasons. Cooking time was standardized with a Mattson cooking device and iron bioavailability was measured with a Caco-2 bioassay, which measures ferritin formation (ng ferritin/mg cell protein) relative to a navy bean reference control (cv. Merlin) as an indicator of iron uptake. Iron concentration was measured via inductively coupled plasma emission spectroscopy (ICP-ES). Iron concentrations of the cooked beans were highly variable across Uganda with low board sense heritability (plot basis 0.40). Iron concentrations in cooked seed ranged from 41 to 97 mg/g, with a mean of 67 mg/g across the nine production environments. Iron bioavailability ranged from 8 to 116% of navy bean control and was highly heritable (plot basis 0.80) among this subset of white, yellow and red beans. The fast cooking white (Blanco Fanesquero) and two Manteca yellow beans consistently had the highest iron bioavailability (64 – 116% of control) across all locations in Uganda. There was a significant negative association (r = −0.438, p ≤ 0.05) between cooking time and iron bioavailability of the white, yellow and red beans produced in Uganda. This study demonstrates the high iron bioavailability trait of the two fast cooking Manteca yellow beans are stable across different production environments in Uganda. This study presents evidence that breeding for fast cooking times in yellow beans is not only a valuable end-use quality trait beneficial to smallholder farmers in Uganda, but could also be a sustainable approach for delivering more bioavailable iron to consumers in East Africa. The high variability of Fe concentration within genotypes raises concern that high Fe concentration can be a sustainable trait in Uganda. U.S. Agency for International Development (USAID), U.S. Department of Agriculture (USDA).

  DOI

• Iron Biofortification of the Common Bean: Assessment of Bean Iron Concentration and Iron Bioavailability from Markets and Breeder Collections in East Africa

  Current Developments in Nutrition · 2020 · 1 citations

  1st authorCorresponding
  • Horticulture
  • Chemistry
  • Geography

  To assess the practicality and assumptions of the high Fe concentration approach for bean Fe biofortification in east Africa. A collection of 76 marketplace samples (East Africa Marketplace Collection; EAMC) were assembled, consisting of multiple color classes from locations in Uganda, Rwanda, Democratic Republic of Congo, Burundi, Ethiopia, Kenya and Tanzania. In addition, because market samples can be a mixture of seed varieties within a market class, 170 samples from the Africa CIAT Collection were also assembled that represent beans of common markets in the region. Iron concentration was measured via inductively coupled plasma emission spectroscopy (ICP-ES) and Fe bioavailability via an established Caco-2 cell bioassay. Using these measures, the following assumptions of high Fe bean Fe biofortification approach were assessed: 1) the average Fe concentration in beans currently consumed in east Africa is approximately 50 μg/g (dry weight), 2) a 40 μg/g increase (target value 90 μg/g) can be sustained through traditional breeding, and 3) iron bioavailability from the biofortified bean will not decrease substantially to negate the increase in Fe concentration. The average EAMC bean Fe concentration was 72 μg/g, ranging from 52–93 μg/g, with a couple of outlying varieties at 105 μg/g (MAC9) and 129 μg/g (MAC49). The Africa CIAT collection averaged 67.5 μg/g with a range of 51–90 μg/g. The 18 biofortified varieties within the EAMC averaged 73 μg/g (range of 55–94 μg/g), which is essentially equal to the overall mean (70 μg/g) and range (54–93 μg/g) of the non-biofortified bean varieties in the EAMC. Using a Caco-2 cell bioassay to measure Fe bioavailability of the EAMC, the biofortified varieties did not deliver any additional Fe relative to non-biofortified varieties. The results indicate that the assumptions of the high Fe bean breeding approach are not met in the typical east African market place. Furthermore, based on the Fe content and bioavailability data collected from this study, the biofortified bean varieties from these markets are providing no additional dietary Fe. An alternative approach for bean Fe biofortification, such as enhanced Fe bioavailability should be pursued. USDA.

  DOI

Frequent coauthors

• Dennis D. Miller

  6 shared

• Jason A. Wiesinger

  Robert W. Holley Center for Agriculture & Health

  5 shared

• Zhiqiang Cheng

  Henan Normal University

  4 shared

• Elad Tako

  Cornell University

  4 shared

• Karen A. Cichy

  Michigan State University

  3 shared

• Chi Kong Yeung

  California Polytechnic State University

  3 shared

• Ross M. Welch

  3 shared

• Jonathan J. Hart

  2 shared

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