Kamala Sohonie Took a Cambridge PhD in 1939, Co-Wrote a Nature Letter on Cytochrome Oxidase in Plants With Robin Hill and Went On to Test Neera as a Low-Cost Source of Vitamins

Kamala Bhagvat, who became Kamala Sohonie after her marriage, took a doctorate from Cambridge in 1939. Her name is on a Nature letter of 29 April 1939, written with the plant physiologist Robin Hill, and on two more Nature letters from Bombay in 1954 and 1955. Between those came vitamin assays at the Nutrition Research Laboratory in Coonoor and, from 1947, food chemistry at the Royal Institute of Science in Bombay, where she later became director.

A first-class degree in 1933 and a probation year at Bangalore

The Institute of Science in Mumbai, which she later led, gives her birth as 18 June 1911. Google’s 2023 Doodle and Resonance, a journal of the Indian Academy of Sciences, give the same date. Narayanrao Bhagvat, her father, and his brother Madhavrao were chemists, and Resonance says they were among the first chemistry students to graduate from the Tata Institute in Bangalore, now the Indian Institute of Science. She finished first in the University of Bombay’s BSc examination in physics and chemistry in 1933 and applied to follow them there.

Bangalore refused her at first. Both Resonance and Lilavati’s Daughters, the Academy’s collection of lives of Indian women scientists, say its director, C. V. Raman, then admitted her on one year’s probation. They add that he later admitted other women. Resonance lists his conditions, among them that she work under supervision late into the night and not distract male colleagues, and notes that almost no first-hand record of the exchange survives. Quartz, drawing on the institute’s own archive site, says IISc had admitted only two women before her, a Miss M. M. Mehta in 1920 and a Miss R. K. Christie in 1922. That makes her 1933 admission the first for a woman in years rather than the first ever.

At Bangalore she worked under the biochemist M. Sreenivasaya on the proteins and nitrogen compounds in milk, pulses and legumes. By 1936 she had five papers, Resonance counts, two of them in the Biochemical Journal. Written with Sreenivasaya and published in April 1935, the first is titled “The non-protein nitrogen of pulses”. In Resonance’s summary, it characterised that fraction in nine well-known Indian pulses and showed it contained the simpler peptides, small chains of amino acids, that are easy to digest. A second Biochemical Journal paper in 1936 partitioned the nitrogen and determined the essential amino acids. A master’s degree followed in 1936, with distinction, the Institute of Science says.

Cambridge, and a letter in Nature

After a short spell at the Haffkine Institute in Bombay in 1937, Resonance says, she joined the Cambridge group of the biochemist Derek Richter. Two papers from that laboratory carry her name. “Animal phenolases and adrenaline” (1938), with Richter, appeared in the Biochemical Journal, and so did “Amine oxidase” (1939), with Richter and H. Blaschko, whose affiliations on the paper are the Biochemical and Physiological Laboratories at Cambridge and the Maudsley Hospital in London.

When Richter left, she moved to Hill’s group, which was working on plant tissue. That produced a letter to Nature dated 29 April 1939, with Hill as first author and K. Bhagvat second, both listed at the School of Biochemistry, Cambridge. Its abstract is two sentences long. Keilin first described the absorption spectrum of cytochrome in living flowering plants in 1925, the abstract says, and the authors had prepared, from germinating seeds and other tissues of monocotyledons and dicotyledons, “an insoluble residue showing the complete cytochrome spectrum”. Cytochromes are proteins that take part in the chain of reactions by which cells release energy, and cytochrome oxidase is an enzyme of that chain.

Higher plants have a true cytochrome oxidase and a respiratory mechanism like that of yeast and animals, Hill and Bhagvat concluded in the full text, according to Resonance. The work, it says, involved isolating and characterising succinate dehydrogenase as well as cytochrome oxidase from those tissues.

Her doctoral thesis described the cytochrome system in plant respiration. Lilavati’s Daughters says the research and writing took under 14 months from her arrival and ran to 40 typed pages. The figure of 14 months also appears in the Institute of Science’s profile, and Resonance gives 40 pages. Resonance calls her the first Indian woman to receive a doctorate from Cambridge. She then took a fellowship in the laboratory of Frederick Gowland Hopkins, it adds, and it could find no paper from that stay.

Vitamins at Coonoor

In 1939 she returned to India as professor and head of the newly opened biochemistry department at Lady Hardinge Medical College in Delhi, then became assistant director of the Nutrition Research Laboratory at Coonoor. Why she left Cambridge when she did is unclear, Resonance says. Resonance quotes her son Anil Sohonie, who says she was patriotic and wished to contribute to the freedom movement.

At Coonoor the main task, Resonance says, was to build reliable chemical and microbiological methods for measuring vitamins in food. By 1944 it had a steady run of papers on ascorbic acid (vitamin C), thiamin (vitamin B1) and nicotinic acid, and by 1947 at least sixteen articles. Its reference list also has a 1946 study of the toxic effects on guinea pigs of diets heavy in Lathyrus sativus, the pulse known as khesari dal.

Beans, fish and two more Nature letters

After her marriage to the actuary Madhav Sohonie she moved to Bombay in 1947 and joined the new biochemistry department at the Royal Institute of Science as professor. At Bombay, the Institute of Science says, her work with students centred on the nutritional value of legumes and staple foods eaten by poor communities. Three strands run through it in Resonance’s account: trypsin inhibitors and thiaminase, the protein and nutrient content of foods, and neera.

Thiaminase is an enzyme that breaks down thiamin. A Nature letter of 13 March 1954, by S. T. Deolalkar and Kamala Sohonie from the Biochemistry Department of the Institute of Science, Bombay, opens by noting earlier reports that fish might hold more than one thiaminase. Its authors set out to investigate thiaminases from different varieties of fish, and the title names freshwater, brackish-water and saltwater fish. Fish popular around Bombay were among those her group studied, Resonance adds.

Trypsin is a digestive enzyme, and a trypsin inhibitor is a substance in a food that blocks it. The Nature letter of 19 March 1955, by Sohonie and K. S. Ambe, begins from an earlier finding by M. K. Gaitonde and Sohonie, reported while studying how well Indian pulses are digested, that field bean, Dolichos lablab, contains one. A simple method of obtaining the field bean inhibitor in crystalline form is described, and the title extends the work to the double bean. Kunitz, Bowman and Tauber had earlier crystallised similar inhibitors from soybean, navy bean and lima bean, the letter notes. A further Nature letter of 1955, on a crystalline inhibitor from potato, appears in Resonance’s list, and it says the group went on to study how such inhibitors affect protein digestibility.

Neera and the Rashtrapati Award

Three sources, the Institute of Science, Resonance and Lilavati’s Daughters, say her neera work began on a suggestion from the President, Rajendra Prasad. Neera is the sweet sap collected from the flower stalks of palms. According to the Institute of Science, her research found useful amounts of vitamin A, vitamin C and iron in it and showed that these nutrients can stay present when the sap is boiled down to palm jaggery and molasses. In Resonance’s account the findings were good vitamin C content and sulfhydryl compounds, sulphur-containing molecules, that protected the vitamins in storage. Its reference list gives papers she wrote with students in Current Science in 1952 and 1953 on the stability of vitamin C in date palm neera at 37 degrees Celsius, on sulfhydryl compounds in neera by paper chromatography and on vitamins in palm jaggery.

Lilavati’s Daughters says she had her students run the work on neera samples from all over the country, that they worked for 10 to 12 years and always got the same results, and that introducing neera into the diet of malnourished tribal adolescents and pregnant women brought a significant improvement in health. She then promoted the drink and the jaggery for children and pregnant women, Resonance says. She received the Rashtrapati Award for the work, though none of the sources gives the year.

Fresh neera is perishable. A 2013 article in the Indian Coconut Journal by a Coconut Development Board officer says it ferments naturally within a few hours of extraction at ambient temperature unless treated. Two Mysore bodies, the Central Food Technological Research Institute and the Defence Food Research Laboratory, developed a way of packing and preserving it for up to 45 days, the article adds. That article concerns coconut neera in Karnataka and does not mention her work.

Director, consumer advocate, and the later honours

Gale’s dictionary entry has her teaching at the Institute of Science from 1949 and directing it from 1965 to 1969, while the Institute’s own profile gives 1947 as the year she joined and no dates for the directorship. Lilavati’s Daughters says she was kept from the post for four years before she got it, and quotes Richter on hearing the news: she had “made history by being the first lady Director of such a big science institute”.

She retired in 1969 and then, Resonance says, served the Consumer Guidance Society of India, one of whose founder members she was, designed a kit housewives could use to test food for purity and wrote science books for students in Marathi. Her presidency of the society in 1982 to 1983 is recorded by the Institute of Science. In 1997 she received the National Award for Excellence and Contribution to Science, Resonance says, and the Indian Council of Medical Research held a programme to honour her, at which she collapsed on the stage. She died on 28 June 1998 in New Delhi, according to the Institute of Science. Google marked her 112th birthday with a Doodle on 18 June 2023.

Where the accounts differ

Birth dates differ: 18 June 1911 in the Institute of Science profile, in Resonance and in Google’s Doodle, but 18 July 1911 in the Gale entry. Both the Institute and Google say she was born in Indore, the Doodle citing family records, while Resonance says Bombay.

The word “first” needs care. Each of the Institute, Google and Resonance describes her as the first Indian woman to earn a doctorate in a science or from Cambridge. A memoir of E. K. Janaki Ammal by the Indian National Science Academy records a DSc from the University of Michigan in 1931, and the John Innes Centre says she was one of the first women from India to obtain a PhD in botany there. Asima Chatterjee holds a separate first, the 1944 D.Sc. from an Indian university.

Popular summaries, including Google’s Doodle, say Sohonie discovered cytochrome c. Yet the 1939 Nature letter credits Keilin with the plant cytochrome spectrum in 1925, and Resonance’s own account of her work is of cytochrome oxidase and the cytochrome system as a whole. On the Institute of Science’s page she identified cytochrome c in plant cells, and the thesis itself was not available to check.

Gale has her working with Hopkins at Cambridge, the Institute of Science with Richter and then Hill, and Resonance with all three in turn.