''Hanseniaspora opuntiae'' is a species of

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

in the family

Saccharomycetaceae The Saccharomycetaceae are a family of yeasts in the order Saccharomycetales that reproduce by budding. Species in the family have a cosmopolitan distribution, and are present in a wide variety of habitats, especially those with a plentiful suppl ...

. It has been isolated from locations worldwide, on grape berries and on prickly pear cacti.

Taxonomy

Samples of ''H. opuntiae'' were first isolated from samples taken from prickly pear cacti in

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

. The species was first described by Neža Čadež, Gé A. Poot, Peter Raspor, and Maudy Th. Smith in 2003 and given the

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

refers to the genus of the host plant where it was first isolated. Genetic sequencing shows that the species is closely related to '' Hanseniaspora lachancei'', ''

Hanseniaspora pseudoguilliermondii ''Hanseniaspora pseudoguilliermondii'' is a species of yeast in the family Saccharomycetaceae. Originally isolated from orange juice concentrate, it has been found on fruit and fruit juices in locations around the world. It has also been obser ...

'', and ''

Hanseniaspora guilliermondii ''Hanseniaspora guilliermondii'' is a species of yeast in the family Saccharomycetaceae. In its anamorph form, it is called ''Kloeckera apis''. Taxonomy The initial sample of the species was isolated by South African pathologist Adrianus Pij ...

''. The four species can only be differentiated from those species by using PCR fingerprinting and not by conventional physiological criteria.

Description

Microscopic examination of the yeast cells in YM liquid medium after 48 hours at 25°C reveals cells that are 3.0 to 16.0 μm by 1.5 to 5.0 μm in size,

apiculate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

ovoid An oval () is a closed curve in a plane which resembles the outline of an egg. The term is not very specific, but in some areas (projective geometry, technical drawing, etc.) it is given a more precise definition, which may include either one or ...

to elongate, appearing singly or in pairs. Reproduction is by

budding Budding or blastogenesis is a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. For example, the small bulb-like projection coming out from the yeast cell is know ...

, which occurs at both poles of the cell. In broth culture, sediment is present, and after one month a very thin ring and a sediment is formed. Colonies that are grown on malt agar for one month at 25°C appear cream-colored, butyrous, glossy, and smooth. Growth is flat to slightly raised at the center, with an entire to slightly undulating margin. The yeast forms poorly developed

pseudohyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or ...

on cornmeal or potato agar. The yeast has been observed to form four hat-shaped

ascospores An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or ...

when grown for at least seven days on 5% Difco malt extract agar. The yeast can ferment

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...

and

cellobiose Cellobiose is a disaccharide with the formula (C6H7(OH)4O)2O. It is classified as a reducing sugar. In terms of its chemical structure, it is derived from the condensation of a pair of β-glucose molecules forming a β(1→4) bond. It can be hyd ...

, but not

galactose Galactose (, '' galacto-'' + '' -ose'', "milk sugar"), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molec ...

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined ...

maltose } Maltose ( or ), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two- ...

lactose Lactose is a disaccharide sugar synthesized by galactose and glucose subunits and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from ' (gen. '), the Latin word for milk, plus the suffix '' - ...

raffinose Raffinose is a trisaccharide composed of galactose, glucose, and fructose. It can be found in beans, cabbage, brussels sprouts, broccoli, asparagus, other vegetables, and whole grains. Raffinose can be hydrolyzed to D-galactose and sucrose by ...

trehalose Trehalose (from Turkish '' tıgala'' – a sugar derived from insect cocoons + -ose) is a sugar consisting of two molecules of glucose. It is also known as mycose or tremalose. Some bacteria, fungi, plants and invertebrate animals synthesize it ...

. It has a positive growth rate at 37°C, but there is no growth at 40°C. It can grow on agar media containing 0.1% cycloheximide and 10% sodium but growth on 50% glucose-yeast extract agar is weak. It has been shown to thrive during the early stages of fermentation of alcoholic beverages, but has a relatively low alcohol tolerance and activity decreases as alcohol levels increase.

Ecology

Strains of the species have been isolated from rot occurring on prickly pear plants in Hawaii as well as on grape berries and wine in Australia, Greece, and China. A 2010 study found that ''H. opuntiae'' was the prevalent species involved with the post-harvest fermentation of

cocoa bean The cocoa bean (technically cocoa seed) or simply cocoa (), also called the cacao bean (technically cacao seed) or cacao (), is the dried and fully fermented seed of ''Theobroma cacao'', from which cocoa solids (a mixture of nonfat substances ...

s on a plantation in Malaysia. It is not known whether it has any human pathogenic potential, but it can grow at a normal body temperature.

Effects on wine production

A study on the effects of co-fermentation of wine with ''H. opuntiae'' and commercial wine yeast found that ''H. opuntiae'' increased the output of certain

fusel alcohol Fusel alcohols or fuselol, also sometimes called fusel oils in Europe, are mixtures of several higher alcohols (those with more than two carbons, chiefly amyl alcohol) produced as a by-product of alcoholic fermentation. The word ''Fusel'' is Ger ...

s which improved the aroma qualities of the finished wine. It also reduced the production of fatty acids in the wine, which contribute negative effects on wine aromas when they are present above their sensory threshholds. Co-fermentation with ''H. opuntiae'' increased the production of

phenylacetaldehyde Phenylacetaldehyde is an organic compound used in the synthesis of fragrances and polymers. Phenylacetaldehyde is an aldehyde that consists of acetaldehyde bearing a phenyl substituent; the parent member of the phenylacetaldehyde class of compound ...

, which lends a desirable floral and honey smell in wine. A different study examining the sequential fermentation of wine with ''H. opuntiae'' followed by commercial wine yeast after 7 days found an increase in the production of

glycerol Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...

ethyl acetate Ethyl acetate ( systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues ...

, several

monoterpene Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen funct ...

s and a decrease in the production of

decanoic acid Capric acid, also known as decanoic acid or decylic acid, is a saturated fatty acid, medium-chain fatty acid (MCFA), and carboxylic acid. Its formula is CH3(CH2)8COOH. Salts and esters of decanoic acid are called caprates or decanoates. The term ...

, fatty acid esters, and final alcohol content. Blind sensory panels in the study compared two wines produced from the same must; the first fermented with a commercial wine yeast, and the second fermented with ''H. opuntiae'' for seven days followed by a sequential fermentation with the commercial wine yeast. Panelists used negative descriptors such as "alcohol", "overripe fruit", and "vegetable", along with positive descriptors "spicy" and "black fruits" to describe the wine fermented only with the commercial wine yeast. The sequentially fermented wine was associated with positive descriptors such as "coffee", "hazelnut", "caramel", and "cherry", along with negative descriptors of "acetone". The panelists were able to detect clear differences in the wines fermented with ''H. opuntiae'' compared to commercial wine yeast alone, with a general preference expressed for the mixed culture wines.

References

{{Taxonbar, from=Q10517388 Saccharomycetes Yeasts Fungi described in 2003