Changes in Esculeoside A Content in Different Regions of the Tomato Fruit during Maturation and Heat Processing

2011 ◽  
Vol 59 (8) ◽  
pp. 4104-4110 ◽  
Author(s):  
Akiko Katsumata ◽  
Mizuki Kimura ◽  
Hiromi Saigo ◽  
Kei Aburaya ◽  
Masako Nakano ◽  
...  
2019 ◽  
Vol 61 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Masaru Nakayasu ◽  
Ryota Akiyama ◽  
Midori Kobayashi ◽  
Hyoung Jae Lee ◽  
Takashi Kawasaki ◽  
...  

Abstract Tomato plants (Solanum lycopersicum) contain steroidal glycoalkaloid α-tomatine, which functions as a chemical barrier to pathogens and predators. α-Tomatine accumulates in all tissues and at particularly high levels in leaves and immature green fruits. The compound is toxic and causes a bitter taste, but its presence decreases through metabolic conversion to nontoxic esculeoside A during fruit ripening. This study identifies the gene encoding a 23-hydroxylase of α-tomatine, which is a key to this process. Some 2-oxoglutarate-dependent dioxygenases were selected as candidates for the metabolic enzyme, and Solyc02g062460, designated Sl23DOX, was found to encode α-tomatine 23-hydroxylase. Biochemical analysis of the recombinant Sl23DOX protein demonstrated that it catalyzes the 23-hydroxylation of α-tomatine and the product spontaneously isomerizes to neorickiioside B, which is an intermediate in α-tomatine metabolism that appears during ripening. Leaves of transgenic tomato plants overexpressing Sl23DOX accumulated not only neorickiioside B but also another intermediate, lycoperoside C (23-O-acetylated neorickiioside B). Furthermore, the ripe fruits of Sl23DOX-silenced transgenic tomato plants contained lower levels of esculeoside A but substantially accumulated α-tomatine. Thus, Sl23DOX functions as α-tomatine 23-hydroxylase during the metabolic processing of toxic α-tomatine in tomato fruit ripening and is a key enzyme in the domestication of cultivated tomatoes.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Pablo D. Cárdenas ◽  
Prashant D. Sonawane ◽  
Uwe Heinig ◽  
Adam Jozwiak ◽  
Sayantan Panda ◽  
...  

AbstractThe genus Solanum comprises three food crops (potato, tomato, and eggplant), which are consumed on daily basis worldwide and also producers of notorious anti-nutritional steroidal glycoalkaloids (SGAs). Hydroxylated SGAs (i.e. leptinines) serve as precursors for leptines that act as defenses against Colorado Potato Beetle (Leptinotarsa decemlineata Say), an important pest of potato worldwide. However, SGA hydroxylating enzymes remain unknown. Here, we discover that 2-OXOGLUTARATE-DEPENDENT-DIOXYGENASE (2-ODD) enzymes catalyze SGA-hydroxylation across various Solanum species. In contrast to cultivated potato, Solanum chacoense, a widespread wild potato species, has evolved a 2-ODD enzyme leading to the formation of leptinines. Furthermore, we find a related 2-ODD in tomato that catalyzes the hydroxylation of the bitter α-tomatine to hydroxytomatine, the first committed step in the chemical shift towards downstream ripening-associated non-bitter SGAs (e.g. esculeoside A). This 2-ODD enzyme prevents bitterness in ripe tomato fruit consumed today which otherwise would remain unpleasant in taste and more toxic.


1991 ◽  
Vol 82 (2) ◽  
pp. 237-242 ◽  
Author(s):  
Erik Knegt ◽  
Evert Vermeer ◽  
Caroline Pak ◽  
Johan Bruinsma
Keyword(s):  

2020 ◽  
Vol 54 (6) ◽  
pp. 410-416
Author(s):  
Joyce M. Hansen ◽  
Scott Weiss ◽  
Terra A. Kremer ◽  
Myrelis Aguilar ◽  
Gerald McDonnell

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2, has challenged healthcare providers in maintaining the supply of critical personal protective equipment, including single-use respirators and surgical masks. Single-use respirators and surgical masks can reduce risks from the inhalation of airborne particles and microbial contamination. The recent high-volume demand for single-use respirators and surgical masks has resulted in many healthcare facilities considering processing to address critical shortages. The dry heat process of 80°C (176°F) for two hours (120 min) has been confirmed to be an appropriate method for single-use respirator and surgical mask processing.


2017 ◽  
Vol 4 (1) ◽  
pp. 36-47
Author(s):  
R. Osae G. Essilfie J. O. Anim

The study was conducted to assess the effect of different waxing materials on the quality attributes of tomato fruits. A 2 x8 factorial experiment layout in complete randomized design with 16 treatment combinations and 3 replication was adopted.The materials that were used for the experiment are two (2) varieties of tomatoes (Pectomech and Power Rano) and seven(7) waxing material (shea butter, cassava starch, beeswax, and a combination of shea butter + cassava starch, shea butter + beeswax, cassava starch + beeswax, shea butter + cassava starch + beeswax) and a control. Results from the experiment indicated that all waxing treatments delayed the development of weight loss, firmness, pH, total soluble solids, and total titrable acidity. The results also suggested that edible wax coatings delayed the ripening process and colour development of tomato fruits during the storage period and extended the shelf life. However Beewax treatment and its combinations performed better than the other treatments. It was therefore recommended that locally produced wax such as Beewax, Shea butter, Cassava Starch treatments and their combinations could be a good technology for preserving the quality and extending the shelf life of fresh tomato fruit as well as maintaining the physical and chemical properties.


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