,(;')
PEA1.53 Check ofthe grape pigment adsorption inthree generations of yeasts Andrea Caridi {7},R Sidari {7}
{7} Mediterranea University ofReggio Calabria, Italy
Inorderto check theGrape PigmentAdsorption (GPA)phenotype in wine yeasts,23strains of Saccharamycescerevisiae-:
wild types,16single-spore descendants and 4hybridsobtained bycrossing thedescendants - havebeenutilized. The GP~
trait wasstudied both onyeastbiomass,using the chromogenic medium Grape-SkinAgar,and by microvinification trials.
-computer-assisted assessment ofthe biomasscolour ofthe yeasts grown onGrape-SkinAgarwasperformed. The wines pro -ducedby themicrovinification trials have beenanalysed for absorbance at420,520, and 620nm,colour intensity, andFol
in-Ciocalteuindex.Datahaveconfirmed thepossibility to improve wineyeast as regards theGPAtrait. For example,considerinç
thetwo wild types RC029andRC039,the12 single-spore descendantsandthe two hybrid RC029A-1DxRC039C-1C (4) anc
RC029B-1C xRC039C-1C (7)itis evident thatthere is a significant improvement oftheGPAphenotype due totheevolutior
drivenbytheselection andthe breedingprogrammes.Geneticanalysis wasperformed onthe 3 wildtypes.Genome sizes werc
estimated byflow cytometry. Anaploid strainofthelaboratory yeastBY474i wasusedas thestandard and assignedarelative
fluorescence valueof 1.0.A diploid strain Zymaflor F15 andananeuploid strain Anchor NT50 [Bradbury etal.,Antonie va' Leeuwenhoek,2006,89, 27-37) werealsousedascontrol strains.Alithe strains hadgenomesizes consistent with their beinç diploid, so validating the observed results.This study would be veryuseful because demonstrates the possibility toirnprove
wine yeast asregards theGPA trait.
This work wassupported byPRIN2007"Wine strain improvement strategies to enhancered wine safety basedon parietal
adsorption activitv" We are grateful to AndreaPulvirenti for helpin hybridization technique betweensporesthat was conducted at theDepartment of"Scienze Agrarie edegliAlimenti", University ofModena andReggioEmilia,Reggio Emilia,
ltalv We would liketo thank Enrico Cundarifor helpinflow cytometric analysisthat wasconducted at the Institute of Molecular Biology andPathology, CNR, Rome,Italy.
PEA1.54 Grape pigment adsorption is an inheritable OTL of yeasts
Andrea Caridi{7},RSidari{7},ACostantino (1), VCrea (7), C vodolù (J). A Pulvirenti (2). G Blaiotta (3)
{7} Mediterranea University ofReggioCalabria,Italy
(2)University ofModena andReggioEmilia, Italy (3)"FedericoIl'University ofPortici (NA),Italy
Thepurpose ofthis work was the validation of theassumption, formulated ina previousstudy (Caridi etal.,Journal ofAp
-plied Microbiology, 2007,103,735-742), that GrapePigmentAdsorption (GPA)phenotype is aQuantitative TraitLoci (OTL)in
yeasts.Theoenological trait GPA was studied in153wine yeasts- 17wild typestrains of Saccharomycescerevisioeand136 single-spore descendants- bothonyeastbiomass,usingthechromogenic medium Grape-Skin Agar, andby microvinification
trials.Acomputer-assisted assessment ofthe biomasscolour of the yeastsgrown on Grape-SkinAgar wasperformed. The
winesproduced bythe microvinification trials havebeenanalysedfor pH,total acidity, absorbance at420,520,and620nm, colour intensity, andFolin-Ciocalteu index.Datahaveconfirmed that the oenological trait GPA isinheritable andpolygenic; effectively, for eachrelatedparameter -bothconcerning biomass colour and wine analysis-thereareacongruous number ofsingle-spore descendants significantly different from parents.Genetic analysis wasperformed on the10wildtypes having single-spore descendants showing superior fermentation properties. Genome sizeswereestimated by flow cytometry. An
aploid strain of the laboratory yeast BY474i was usedasthe standard and assigned arelative fluorescence value of 1.0. A diploid stra in Zymaflor F15 andan aneuploid strain Anchor NT50(Bradburyet al.,Antonie vanLeeuwenhoek,2006,89,27-37)
were alsousedas control strains.Alithe strainshadgenome sizesconsistent with their being diploid, so validating theinitial
assumption.This validation would be very useful becauseallowsthepossibility toimprovewineyeastasregards the GPAtrait. This work was supported byPRIN2007 "Wine strain improvement strategies toenhanceredwinesafety basedonparietal
adsorption activitv" Wewould liketo thank EnricoCundari forhelp in flow cytometric analysis that was conducted atthe Institute of Molecular Biology andPathology,CNR,Rome,Italy.
