Chinin is the second most plentiful natural polymer. Currently, chitin and chitosan are manufactured commercially in large scale from crab and shrimp shell as fish processing waste. They is being used in many commercial application because of their various functional properties. Chitosan, in particular, is being evaluated as biomedical materials in a number of food and pharmaceutical industries. Despite their potential abilities, the perfect safety had been demonstrated until now. However, the long-term feeding with chitin was not any negative effect the body weights and serum enzymatic activities in mice. And, in rats supplied with $5\%$ of chitosan diet for 450 days, there was no changes of Ca concentration in blood, bone and other organs except for in muscle. Consequently, there was no direct toxicity of chitin and chitosan against some animals such as rat and mouse by recently reports.

Aloe의 추출 시료들 중 혈관생성을 촉진하는 물질이 G1M1D1M1 분획에 있음을 chorioallantoic-membrane(CAM) assay, in vitro angiogenesis assay, u-PA, PAI, u-PAR, 및 matrix metalloprotease(MMP)의 유전자 발현조사, gelatin zymogram assay, modified CAM assay를 하여 확인 하였다. 그런 다음 G1M1D1M1 분획을 다시 분리하여 단일 성분인 NY932와 3종의 분획들을(U>3,000, 3,000>U>1,000, U<1,000) 얻었다. 이들 각각에 대한 혈관 생성 촉진 작용을 CAM assay 방법으로 조사한 결과 순수단일 성분인NY932가 혈관 생성 촉진 활성을 가장 높게 나타났다. 즉 NY932의 농도를 100ng, 2, 10, 35, 60 $\mu$g으로 투여하였을 때, 각각 2/18($11\%$), 4/10($49\%$), 16/22($73\%$), 15/17($88\%$), 9/9($100\%$)의 혈관생성 촉진 효과를 보였다. 따라서 순수 단일 성분인 NY932의 혈관 생성 촉진 작용기전을 규명하기 위하여 혈관 생성에 관련된 효소들[matrix metalloprotease(MMP)s, urokinase-plasminogen activator(uPA) 등]과 그 저해제들(TIMPs, PAI)의 유전자 발현을 조사하였으며, wounding migration assay등을 수행하였다.

By using guinea pig lung mast cells, this study aimed to examine the effects of Aloe component(NY945) on the mediator releases caused by mast cell activation, and also aimed to assess the effects of NY945 on the mechanism of mediator releases in the mast cell activation. We partially purified mast cells from guinea pig lung tissues by using the enzyme digestion, the rough and the discontinuous density percoll gradient method. Mast cells were sensitized with $IgG_1$ (anti-OA) and challenged with ovalbumin. Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay The phospholipase D activity was assessed more directly by the production of labeled phosphatidylethanol or phosphatidylbutanol which was produced by phospholipase D-mediated transphosphatidylation in the presence of ethanol or butanol. The amount of mass 1,2-diacylglycerol was measured by the [$^3H$]1,2-diacylgycerol produced when prelabeled with [$^3H$]myristic acid. In the mast cells prelabeled with L-[$^3H$]methyl methionine the phospholipid methylation was assessed by measuring the incorporation of the [$^3H$]methyl moiety into phospholipids. Pretreatment of NY945(10$\mu$g) significantly decreased histamine and leukotrienes releases during mast cell activation. The decrease of histamine release was stronger than that of leukotrienes during mast cell activation. The phospholipase D activity increased by the mast cell activation was decreased by the dose-dependent manner in the pretreatment of NY945. The amount of mass 1,2-diacylglycerol produced by activation of mast cells were decreased in the pretreatment of NY945. NY945 pretreatment strongly inhibited the incorporation of the [$^3H$]methyl moiety into phospholipids. The data suggest that NY945 purified from Aloe inhibits in part an increase of 1,2-diacylglycerol which is produced by activating mast cells with antigen-antibody complexes which is mediated via phosphatidylcholine-phospholipise D and phosphatidylinositole-phospholipise C systems, and then followed by the inhibition of histamine release. Furthermore, NY945 reduces the phosphatidylcholine production by inhibiting the methyltransfsrase I and II, which decrease the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrines.