• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.40-50
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• 1990

The purpose of this paper is to develop a colorant from krill, Euphausia superba, process wastes for use in food products. Carotenoproteins were extracted from preboiled krill processing offal(PKPO) and raw frozen krill processing offal(RKPO) with the aid of proteolytic enzymes. The long-term stability of the astaxanthin associated with the carotenoprotein by the addition of pretense inhibitor and antioxidant to the product were also investigated. Total astaxanthin contents of PKPO and RKPO were $35.1mg\%,\;22.1mg\%$ and those in carotenoproteins were $98.6mg\%,\;61.9mg\%$, respectively. The chitin contents of PKPO and RKPO were $6.9\%,\;4.5\%$, however, those of carotenoproteins were not determined. When $0.5\%$ trypsin was added to the extraction medium containing 0.5M $Na_3EDTA$ at $4^{\circ}C,\;74\%$ of astaxanthin and $83\%$ of the protein of PKPO were recovered as carotenoprotein in 24hrs. The amino acid profile in carotenoprotein was mainly composed of glutamic acid, methionine, aspartic acid and isoleurine. Their contents amounted to about 40% of the total amino acids, followed by alanine, phenylalanine, Iysine, leucine, threonine and tyrosine in that order, with a small amount of cysteine and tryptophan. The levels of essential amino acids were high as much as $38.3\%\~43.6\%$ of the total amino acids. The maximum observance of the carotenoid fraction from krill processing offal and from carotenoprotein was 469nm in petroleum ether. The separated components of carotenoprotein by TLC had Rfs $0.20\~0.23\;0.56\~0.60$ and $0.88\~0.91$. The carotenoids were comprised of astaxanthin, astaxanthin monoester and asthaxanthin diester in $25\~30\%\;,35\~40\%$and $40\~45\%$, respectively. The loss of carotenoids in the carotenoprotein can be prevented by the addition of pro-tease inhibitor(trasylol) and antioxidant(BHT) below $4^{\circ}C$.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.731-742
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• 2014

In the current study, we investigated effects of a combination of earthworm casting, environment-friendly by-product fertilizer, and cultivation soil of Gymnocalycium mihanovichii in a heavy fertilizing culture on diameter, height, numbers of tubercles, and chemical properties of soil thereby elucidating optimal mixture ratio for securing production as well as providing nutrients throughout cultivation period. The Gymnocalycium mihanovichii var 'Ihong', one of grafted cactus for export (Rootstock: 9 cm, Scion: $1.5{\times}1.3cm$ grafted cactus) was cultured in plastic houses of Agricultural Technology Center located in Naegok-dong, Seocho-gu, Seoul from June, 2013 through December, 2013. For the control group, a mixture of sand and fertilizer (50:50) was used as this ratio is widely utilized in farmhouses. In contrast, a variety mixtures of sand and earthworm casting that was produced with food wastes was compared; the mixture ratios were 80:20, 60:40, 40:60, 20:80, and 0:100 and pH for these mixtures were found to be similar each other (ranging between 7.1 and 7.4) which is in an appropriate range (pH 6.5-7.5) for cultivation of G. mihanovichii. The organic content was increasing along with increasing contents of earthworm casting ratio while it was lower than the treatment practice group (32-43 mg/kg vs. 55 mg/kg). The content of exchangeable cation was also increasing as the ratio of earthworm casting was elevated; although levels of $K^+$, $Na^+$, and $Mg^{2+}$ were lower than the treatment practice group, the level of $Ca^{2+}$ was higher ($9.1cmol^+/kg$ and $11.5-33.7cmol^+/kg$ in the treatment practice group and the earthworm casting group, respectively). Three months after grafting, diameters of G. mihanovichii were compared with the control group; consequently, there was a significant difference noted in between the earthworm casting group and the control group (31.39 mm vs. 32.46-37.59 mm). After 5 months, growth characteristics of G. mihanovichii were evaluated. Similarly, the diameter of G. mihanovichii was significantly increasing in the group with higher ratio of earthworm casting treatment (32.63 mm vs. 32.49-37.59 mm). The height of tubercles was 2.63 mm in the control group while it was significantly elevating along with the ratio of earthworm casting mixture. The more numbers of tubercles, the more incomes for farm-houses; as results, higher mixture ration of earthworm casting resulted more numbers of tubercles compared to the control group (2.7 vs. 3.2-8.3 ea). In particular, in the earthworm casting groups with 80% and 100% ratios, the numbers of tubercles were 6.2 and 8.3 ea, respectively, which is 2.5 times more than those of the control group. These results indicate that earthworm casting treatment may be utilized in G. mihanovichii farming houses for short term production of tubercles. In the group with 40% and 60% of earthworm casting mixture, the numbers of tubercles were found to be 4.5 and 4.8 ea, respectively which is higher than the control group as well; in these groups, there were no issues with soil drainage as well as moss formation. Given the analysis results of growth characteristics of G. mihanovichii, it was concluded that 40% and 60% of earthworm casting mixture might be the optimal ratios.