Cryopreservation Of The Free Living Conchocelis Of Porphyra Yezoensis Ueda (03D) By Encapsulation-dehydration

Conchocelis　of　the　algae　Porphya　yezoensis　Ueda　03C　and　03D　were　preservation　using　encapsulation-dehydration.　In　the　study　of　cryopreservation,　conchocelis　were　encapsulated　in　3%　Ca-alginate　beads　with　30‰　NaCl.　Beads　were　desiccated　with　silica　gel　then　directly　immersed　in　liquid　nitrogen.　The　main　factors　influencing　the　viability,　such　as　dehydration　rate,　water　content　and　thawing　temperature　were　studied.　The　results　are　as　follows:　1.　Effect　of　dehydration　rate　on　viability　At　different　dehydration　rate　(a　water　reduction　per-hour　1%,　5%,　7.5%,　10%,　15%),　two　algae　both　obtained　highest　viabilities　at　the　dehydration　rate　of　7.5%　water　content/h.　2.　Effect　of　water　content　At　an　average　dehydration　rate　of　7.5%　water　content/h,　water　contents　in　beads　had　more　effects　on　viability　after　thawing　than　after　dehydration.　Both　algae　have　the　same　optimum　water　content　that　is　25%.　The　highest　viabilities　are　68.8%　and　30.1%　respectively.　3.Effect　of　thawing　temperature　In　this　part,　cochocelis　of　Porphya　yezoemsis　Ueda　03D　was　studied.　Beads　were　dehydrated　to　25%　water　content　at　an　average　dehydration　rate　of　7.5%water　content/h,　and　then　immersed　in　liquid　nitrogen.　Different　thawing　temperature　(0,　20,30,　40,　50℃)　were　chased.　The　results　indicated　that　the　viabilities　remarkably　higher　from　30℃　to　50℃　than　from　0℃　to　20℃.　The　optimum　thawing　temperature　was　30℃,　its　highest　viability　was　34.8%.　Then,　conchocelis　of　Porphya　yezoensis　Ueda　03D　were　preserved　in　usual　temperature　by　encapsulation-dehydration.　The　dehydrated　beads　were　remained　under　different　condition　(20℃　under　light　and　in　darkness,　4℃　and　-20℃　in　darkness).　The　results　are　as　follow:　under　4℃,　the　beads　which　have　higer　water　content　have　the　highest　viability　and　the　preservation　time　is　the　longest.