| In China and even all over the world, Porphyra is one of the most important economic seaweed algae. In China, Prophyra yezoensis and Prophyra haitanensis were the main two cultivating Porphyra. Not only the tastes well, but also the nutritional value great, so Porphyra was attracted to consumers. The tested materials were harvested from Nantong Porphyra cultivating firms in Jan., Feb., Mar. of2012year. The fatty acids composition, volatile organic compounds (VOCs) composition, and free amino acids contents and composition were studied in this paper, drawing the data to support the quality analysis and sorted procressing of Prophyra yezoensis.The fatty acid composition profile of Porphyra yezoensis of different strain in different harvesting time were analyzed using a modified Bligh-Dyer method and gas chromatography-mass spectrometry(GC-MS). Results indicated that the fatty acid composition of samples in different harvesting time was consistent, but the content of fatty acid among samples was significantly different. The saturated fatty acids (SFAs) were mainly composed of130,160,180, with160as the the highest component (about20%). Among the unsaturated fatty acids (UFAs) contained18:1n-9,182n-6,183n-3,20:1n-9,202n-7,203n-7,20:4n-6(AA),20:5n-3(EPA), the major composition was EPA (about50%). The concentration of total fatty acids and EPA was highest in samples harvested in Feb.indicated that low temperature was propitious to the accumulation of fatty acids especially UFAs. P. yezoensis was rich in UFAs, especially EPA, and the n-6/n-3ratios ranged from4.9to7.7was consistent with the recommending ratio of WHO/FAO. Thus, P.yezoensis will play a key role in dietary balance and the health condition improvement of human.The volatile organic compounds (VOCs) in Prophyra yezoensis was studied with headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) techniques. The results indicated that the VOCs comprised of hydrocarbon, alcohols, aldehyde, ketone, esters and other compounds, paraffin hydrocarbon and alkene were the main compounds of hydrocarbon. The carbochain length of paraffin hydrocarbon was10～20, and the relative contents of Undecane, Dodecane, Tridecane, Tetradecane, Pentadecane, Hexadecane and Heptadecane was significant. The carbochain length of alkene was7～19, and the relative contents of8-Heptadecene was highest. The carbochain length of alcohols was8～20, and the relative contents of Matsutakeol, Cyclooctanol, Cedrol, Undecanol, Pentadecanol, Hexadecanol, Heptadecanol was sigmheant. The carbochain length of aldehyde was about6-17, and the main compounds were Nonanal, Decanal, Beta cyclocitral, Tridecylic aldehyde, Myristic aldehyde, Pentadecanal. The carbochanin of ketones was8～18, the contents of a-Ionone, Pentadecanone was significant. Some kinds of the esters contents was significant. The relative contents of hydrocarbon, alcohols, aldehyde, ketone, esters ofthe samples harvested in Jan. was sperately52.6%～65.84%,5.21%～11.02%,17.91%～29.89%,0.6%～4.64%,0.91%～7.95%; The relative contents of hydrocarbon, alcohols, aldehyde, ketone, esters ofthe samples harvested in Feb. was sperately63.29%～73.94%,4.61%～9.24%,5.5%～11.35%,0.21%～3.63%,8.03%～14.88%; The relative contents of hydrocarbon, alcohols, aldehyde, ketone, esters of the samples harvested in Mar. was sperately70.52%～82.17%,5.65%～11.91%,3.9%～13.01%,0.28%～0.77%,2.06%～3.37%.The free amino acids of samples were derived with O-phthalaldehyde (OPA) and9-fluorenyl methylchloroforma (FMOC) inprecolumn and separated by RP-HPLC. The results showed that16kinds of free amino acids were indentified, and the total free amino acids of samp Is harvested in Jan. was ranged from5088.07mg/100g to6393.71mg/100g; the total free amino acids of sampls harvested in Feb. was ranged from4893.80mg/100g to6236.18mg/100g;the total free amino acids of sampls harvested in Mar. was ranged from4888.51mg/100g to6066.14mg/100g. The FAA contents of samples2,3,4,6and8was constantly high all over the three months, and the FAA contents of samples harvested in Feb. was highest among the three months’samples.The contents of Ala, Arg, Glu, Asp were significant in all samples, accounting for about80%of the total FAAs. The contents of samples harvested in Jan. ranged from4169.78mg/100g to4834.87mg/100g, The contents of samples harvested in Feb. ranged from4296.87mg/100gto5396.08mg/100g, The contents of samples harvested in Mar. ranged from3605.02mg/100g to4734.45mg/100g. Meanwhile the contents of Ala and Glu were significantly and positively correlated with the total FAAs (P<0.05). The taste amino acids contents of samples harvest in Jan. ranged from2835.43mg/100g to3238.62mg/100g, The taste amino acids contents of samples harvest in Feb. ranged from2889.45mg/100g to3459.35mg/100g, The taste amino acids contents of samples harvest in Mar. ranged from2241.02mg/100g to2942.05 mg/100g. The EAA contents of samples1,2,3,5,6and9was constantly high all over the three months, and the EAA contents of samples harvested in Mar. was highest among the three months’samples.Nostoc comm(?) comnonly namea (?)-can is one (?) worla-wide (?)ole Cyanobacteria, people in the countrys such as China, Japan, Pilipinas, are used to eat it. Nostoc commune is rich in nutritional materials, and is attracted to consumers. The tested materials were from Chinese Academy of Sciences Institute of Hydrobiology.Nostoc commune cultivated in two different conditions (with or without nitrogen in medium) were analyzed for their fatty acids composition using a modified Bligh-Dyer method and GC-MS. The results indicated that C16and C18were dominant compositions of total fatty acids (TFAs), among which the contents of unsaturated fatty acids (UFAs) were all above50%in all tested samples. TFAs contents of N.commune cultivated in medium without nitrogen (BG110) was13.29mg/g, while that of saturated fatty acids (SFAs) and UFAs were present at36.91%,63.09%respectively. C18:1was present at15.99%in particular; TFAs contents of N.commune cultivated in medium with nitrogen (BG11) was7.72mg/g, while contentss of SFAs and UFAs were present at47.91%,52.09%respectively. C18:1was1.74%. The present study showed that the contents of TFAs especially UFAs was significantly (p<0.05) higher in BGllo group than in BG11group. This demonstrated that the absence of nitrogen was propitious to the accumulation of fatty acids especially UFAs.The volatile organic compounds in Nostoc commune cultivated in two different conditions (with and without nitrogen in medium) is studied with headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) techniques.A total of39types of volatile compounds,including normal paraffinhydrocarbons (90.93%),alkenes (3.22%),alcohols (1.88%),esters (0.74%),ketones (2.87%) have been indentified from the Nostoc commune cultivated without nitrogen. And A total of40types of volatile compounds, including normal paraffin hydrocarbons (85.24%),alkenes (3.55%),alcohols (5.93%),esters (1.98%),ketones(1.65%) have been indentified from the Nostoc commune cultivated with nitrogen.Normal paraffin hydrocarbons,alkenes,alcohols,esters and ketones were the main compounds of volatile compounds of Nostoc commune.Among them,the contents of normal paraffin hydrocarbons was high to90%.The effect of nitrogen on the composition of normal paraffin hydrocarbon was significantly.The main compounds in the Nostoc commune cultivated without nitrogen were heptadecane and hexadecane,and in the one cultivated with nitrogen were heptadecane and7-methyl-heptadecane. |
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