trehalulose
{{Distinguish|Trehalose}}
{{chembox
| ImageFile = Trehalulose structure.png
| ImageSize = 200px
| IUPACName = 1-O-α-D-Glucopyranosyl-D-fructose
| OtherNames =
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 34448547
| StdInChI = 1S/C12H22O11/c13-1-4(15)7(17)8(18)5(16)3-22-12-11(21)10(20)9(19)6(2-14)23-12/h4,6-15,17-21H,1-3H2/t4-,6-,7-,8-,9-,10+,11-,12+/m1/s1
| StdInChIKey = NMELTECMHKKXLF-DGQJZECASA-N
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 51411-23-5
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = H39U51DD7Q
| PubChem = 162104
| EINECS = 257-183-7
| ChEBI = 79284
| KEGG = G01400
| SMILES = C(C1C(C(C(C(O1)OCC(=O)C(C(C(CO)O)O)O)O)O)O)O
}}
|Section2={{Chembox Properties
| C=12 | H=22 | O=11
| Appearance =
| Density =
| MeltingPt =
| BoilingPt =
| Solubility =
}}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
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}}
Trehalulose is a disaccharide made up of a molecule of fructose bound to a molecule of glucose. Like isomaltulose, it is a structural isomer of sucrose that is present in small quantities in honey.{{Cite book|editor=Wolfgang Gerhartz |url=https://www.worldcat.org/oclc/311987978|title=Ullmann's encyclopedia of industrial chemistry / Vol. A. Alphabetically arranged articles. 25, Starch and other polysaccharides to surfactants.|date=1994|publisher=VCH Verl.-Ges|isbn=3-527-20125-4|edition=5., completely rev |location=Weinheim|pages=426–427|oclc=311987978}} It makes up 50% of sugars in the honeydew of silverleaf whiteflies{{Cite journal|last1=Salvucci|first1=Michael E.|last2=Wolfe|first2=Gregory R.|last3=Hendrix|first3=Donald L.|date=1997-05-01|title=Effect of sucrose concentration on carbohydrate metabolism in Bemisia argentifolii: Biochemical mechanism and physiological role for trehalulose synthesis in the silverleaf whitefly|url=http://www.sciencedirect.com/science/article/pii/S0022191096001242|journal=Journal of Insect Physiology|language=en|volume=43|issue=5|pages=457–464|doi=10.1016/S0022-1910(96)00124-2|issn=0022-1910}}{{Cite book|url=https://www.worldcat.org/oclc/70262506|title=Dictionary of carbohydrates with CD-ROM|others=Collins, P. M.|date=29 November 2005|isbn=0-8493-7765-X|edition=2nd|location=Boca Raton|pages=538|oclc=70262506}} and is synthesised from sucrose by some bacteria,{{Cite journal|last1=Hamerli|first1=Dénes|last2=Birch|first2=Robert G.|date=2011|title=Transgenic expression of trehalulose synthase results in high concentrations of the sucrose isomer trehalulose in mature stems of field-grown sugarcane|journal=Plant Biotechnology Journal|language=en|volume=9|issue=1|pages=32–37|doi=10.1111/j.1467-7652.2010.00528.x|pmid=20492546|issn=1467-7652|doi-access=free}}{{Cite journal|last1=Tsuyuki|first1=Ken'ichiro|last2=Sugitani|first2=Toshiaki|last3=Miyata|first3=Yukie|last4=Ebashi|first4=Tadishi|last5=Nakajima|first5=Yoshikazu|date=1992|title=Isolation and characterization of isomaltulose- and trehalulose-producing bacteria from Thailand soil.|journal=The Journal of General and Applied Microbiology|volume=38|issue=5|pages=483–490|doi=10.2323/jgam.38.483|issn=1349-8037|doi-access=free}} such as Protaminombacter rubrum. Because the anomeric carbon of the fructose moiety is not involved in the glycosidic bond, it is a reducing sugar.{{Cite book|last1=Rosenplenter|first1=Kurt|url=https://books.google.com/books?id=xAG7yyKWEi0C&pg=PA259|title=Handbuch Süßungsmittel|last2=Lipinski|first2=Prof Dr Gert-Wolfhard von Rymon|last3=Nöhle|first3=Prof Dr Ulrich|date=2007-01-01|publisher=Behr's Verlag DE|isbn=978-3-89947-947-8|page=258|language=de}}
Physiology
Because the fructose and glucose molecules are linked by a 1,1 glycosidic bond, which is more stable than the 1,2 glycosidic bond in sucrose, it is broken down more slowly than sucrose in the small intestine, giving it a lower glycemic index. This more stable bond also means that it cannot be utilised by Streptococcus mutans, and it is therefore non-cariogenic.{{Cite journal|last1=Ooshima|first1=T.|last2=Izumitani|first2=A.|last3=Minami|first3=T.|last4=Fujiwara|first4=T.|last5=Nakajima|first5=Y.|last6=Hamada|first6=S.|date=1991|title=Trehalulose Does Not Induce Dental Caries in Rats Infected with Mutans Streptococci|url=https://www.karger.com/Article/FullText/261376|journal=Caries Research|language=en |volume=25|issue=4|pages=277–282|doi=10.1159/000261376|issn=0008-6568|pmid=1913765}}
Properties
Unlike isomaltulose, trehalulose strongly resists crystallisation, and forms an amorphous solid when dried. Its sweetness relative to sucrose has been estimated as between 0.4{{Cite patent|title=Process for producing a saccharide composition containing trehalulose|pubdate=1997-09-10|country=EP|number=0794259|assign=Hayashibara Seibutsu Kagaku Kenkyujo KK|inventor1-last=Nishimoto|inventor1-first=Tomoyuki|inventor2-last=Chaen|inventor2-first=Hiroto|inventor3-last=Fukuda|inventor3-first=Shigeharu|inventor4-last=Miyake|inventor4-first=Toshio}} and 0.7.{{Cite journal|last1=Ravaud|first1=Stéphanie|last2=Watzlawick|first2=Hildegard|last3=Haser|first3=Richard|last4=Mattes|first4=Ralf|last5=Aghajari|first5=Nushin|date=2005-01-01|title=Expression, purification, crystallization and preliminary X-ray crystallographic studies of the trehalulose synthase MutB from Pseudomonas mesoacidophila MX-45|url=http://scripts.iucr.org/cgi-bin/paper?S1744309104030623|journal=Acta Crystallographica Section F|volume=61|issue=1|pages=100–103|doi=10.1107/S1744309104030623|issn=1744-3091|pmc=1952383|pmid=16508103}}
It has a specific rotation of °.
Honey from stingless bees
In 2020 researchers at the University of Queensland found that some species of stingless bee in Australia, Malaysia, and Brazil produce honey containing between 13% and 44% trehalulose rather than the usual glucose and fructose. The university's findings supported the long-standing claims of Indigenous Australian people that native honey is beneficial for human health.{{Cite web|last=Layt|first=Stuart|date=2020-07-23|title=Scientists say native stingless bee honey hits the sweet spot|url=https://www.brisbanetimes.com.au/national/queensland/scientists-say-native-stingless-bee-honey-hits-the-sweet-spot-20200723-p55eud.html|access-date=2020-07-27|website=Brisbane Times|language=en}}{{Cite journal|last1=Fletcher|first1=Mary T.|last2=Hungerford|first2=Natasha L.|last3=Webber|first3=Dennis|last4=Carpinelli de Jesus|first4=Matheus|last5=Zhang|first5=Jiali|last6=Stone|first6=Isobella S. J.|last7=Blanchfield|first7=Joanne T.|last8=Zawawi|first8=Norhasnida|date=2020-07-22|title=Stingless bee honey, a novel source of trehalulose: a biologically active disaccharide with health benefits|journal=Scientific Reports|language=en|volume=10|issue=1|page=12128|doi=10.1038/s41598-020-68940-0|pmid=32699353|pmc=7376065|bibcode=2020NatSR..1012128F|issn=2045-2322|doi-access=free}} In 2021 the same researchers discovered that the bees convert all sucrose from nectar into trehalulose.{{Cite news|url=https://www.abc.net.au/news/rural/2021-08-28/native-bees-healthy-honey/100409558|title = Native bees make a healthy honey no others make, and now we know how|newspaper = ABC News|date = 27 August 2021}}