Analysis of Leaves of Bruguiera Gymnorrhiza for Its Elementary Chemical Composition

Sample of leaves of Bruguiera gymnorrhiza was analyzed for its elementary chemical composition.Fresh leaf sample was used for the determination of moisture,ash,acid-insoluble substance and sulfur in the ash and etc.Moisture was determined by the 120H electronic moisture determinator,and ash was determined as described in GB 5009.4-1985.Crude protein and fats were determined by the methods given in GB 5009.4-1985 and GB 5009.3-1985 respectively.Air-dried leaves were smashed and taken as sample for determination of micro amounts of inorganic elements and amino acids.Amino acids in the sample were extracted with 6 mol·L-1 HCl and decolored with active carbon.The filtrate obtained was used for determination of amino acid with the automatic amino acid determinator.ICP-AES method was applied to the determination of micro amounts of inorganic elements,with the sample treated in a similar way as in the determination of amino acids.Seventeen amino acids,amounting totally to 14.0 mg·g-1,were found in the leaf-sample,among which 7 amino acids,about 30% of the total,were essential for human health.Fifteen inorganic elements,i.e.B,Ba,Ca,Cu,Fe,K,Mg,Mn,Na,Ni,P,S,Si (soluble),Sr and Zn,were found,most of which were nutritious mineral elements.