• Korean Journal of Soil Science and Fertilizer
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• v.11 no.1
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• pp.9-16
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• 1978

In order to establish a better combination of nutrients of complex fertilizer for apple tree a boron-enriched complex fertilizer ($N-P_2O_5-K_2O-B_2O_5-MgO$: 10 10-0.2-2.0) was compared with various treatments using urea superphosphate, potash muriate, usual complex fertilizer (22-22-11) and borax in its effect on the various growth status such as total leaf weight per tree and shoot growth of dwarf Fuji (1 year old) and super type Starcreamson (3 year old) grown at comparatively poor soils. For Fuji grown on sandy red soils the boron-enriched complex fertilizer (BC) was best and followed by-usual complex fertilizer NPK only, NPK only+Boron, BC+high boron (17times) and no phosphorus in the order. For Starcreamson grown on heavy clayey soils CB+high boron and phosphorus was best and followed by BC, usual complex fertilizer, NPK only, BC+high boron, NPK+boron and no phosphorus in the order. Without compost in the poor heavy clayey soil the growth was worse with high boron and best with NPK+boron and followed by BC Growth was poor with high boron alone but better with phosphorus and high boron, and it was thought that boron was effective when it was distributed in soil with N.P.K. Fertilizer response of apple tree was well appeared on leaf length, new shoot length and total leaf weight per tree. Suitable formulation of a boron-enriched complex fertilizer for apple tree appeared as 10-20-10-0.6 ($N-P_2O_5-K_2O-B_2O_5$) for poor fields and fields with moderate fertility. Chemical analysis of leaves suggested Mg effect on the increase of leaf weight. Effect of Fe was similar to thatof of Mg.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.60-68
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• 2018

A cold-active and alkaline serine protease (Pro21717) was partially purified from the Antarctic marine bacterium Pseudoalteromonas arctica PAMC 21717. On a zymogram gel containing skim milk, Pro21717 produced two distinct clear-zones of approximately 37 kDa (low intensity) and 74 kDa (high intensity). These were found to have identical N-terminal sequences, suggesting they arose from an identical precursor and that the 37 kDa protease might homodimerize to the more active 74 kDa form of the protein. Pro21717 displayed proteolytic activity at $0-40^{\circ}C$ (optimal temperature of $40^{\circ}C$) and maintained this activity at pH 5.0-10.0 (optimal pH of 9.0). Notably, relative activities of 30% and 45% were observed at $0^{\circ}C$ and $10^{\circ}C$, respectively, in comparison to the 100% activity observed at $40^{\circ}C$, and this enzyme showed a broad substrate range against synthetic peptides with a preference for proline in the cleavage reaction. Pro21717 activity was enhanced by $Cu^{2+}$ and remained stable in the presence of detergent surfactants (linear alkylbenzene sulfonate and sodium dodecyl sulfate) and other chemical components ($Na_2SO_4$ and metal ions, such as $Ba^{2+}$, $Mg^{2+}$, $Ca^{2+}$, $Zn^{2+}$, $Fe^{2+}$, $K^+$, and $Na^{2+}$), which are often included in commercial detergent formulations. These data indicate that the psychrophilic Pro21717 has properties comparable to the well-characterized mesophilic subtilisin Carlsberg, which is commercially produced by Novozymes as the trademark Alcalase. Thus it has the potential to be used as a new additive enzyme in laundry detergents that must work well in cold tap water below $15^{\circ}C$.