根據世界衛生組織 (WHO) 之報告，鐵缺乏是全球盛行率最高的營養缺乏問題，鐵缺乏營養問題普遍存在於發展中國家，在先進富裕國家中也未完全解決，全球的盛行率高達 30%。植物性食物中鐵質生體利用率偏低是引起鐵缺乏之主要原因之一。一些研究亦發現鐵缺乏會導致脂質代謝異常。辣木（Moringa oleifera）含有豐富之營養素，在印度及非洲民間廣泛用於膳食中。因此本實驗利用大鼠血紅素再生法，探討辣木葉鐵質之生體可利用率及其對缺鐵導致之脂質代謝異常的改善功效。
採用 3 周齡 Wistar 品系雄鼠，耗鐵期全程自由攝食不含鐵的基礎飼料及二次水，飼養五週後，血紅素值達缺鐵貧血階段，分成五組，使每組各一隻平均體重與血紅素相近，進入再生期階段，包括 D 組 (不添加鐵)，12 C 組 (12ppm FeSO4·7H2O)，24C 組 (24ppm FeSO4·7H2O)，12M組 (12ppm 辣木葉鐵質)，24M 組 (24ppm 辣木葉鐵質)，其中 D 及 M 組再生期全程自由攝食，C 組則與 M 組採對飼育飼養，兩週尾巴採血分析血紅素濃度，五週後犧牲。結果顯示 : 在血紅素濃度與變化量、血紅素總鐵量和血紅素鐵變化量方面，除了缺鐵組維持不變，其餘各組皆有上升趨勢，並且呈現劑量反應。鐵來源硫酸亞鐵 (C組) 相對於辣木葉 (M組) 有較高的鐵質生體可用率。若以硫酸亞鐵為對照組，24M 與 12M 測得的辣木葉分別為50% 與 29%。缺鐵有增加血清三酸甘油酯濃度的趨勢，硫酸亞鐵和辣木葉均有顯著降低缺鐵導致肝臟高三酸甘油酯含量的功效。綜合上述，辣木葉和硫酸亞鐵均可降低血清和肝臟的三酸甘油酯濃度；辣木葉在蔬菜類屬於高鐵質生體可用率的食物，含豐富鐵量的辣木葉，期許未來可應用於改善鐵營養狀況及缺鐵性脂質代謝異常。 World Health Organization (WHO) has reportered iron deficiency is the most commom nutrional disorder in the world. Iron deficiency with or without concurrent anemia affects about 30% of the global population. Although the rates of deficiency are higher in developing countries, many persons living in developed nations also are iron deficient. The major responsible factor of iron deficiency anemia is poor iron bioavailability in the diet. A number of studies has suggested links between Fe deficiency and lipid metabolism alteration. Moringa oleifera plant is rich in nutrient and used as herbal medicines in India and Africa. The purpose of this study was to evaluate the effects of Moringa leaves on iron bioavailability and hepatic lipid metabolism using a rat hemoglobin (Hb) repletion bioassay.
Forty 3-week-old male Wistar-strain rats were used in experiment. In 5-wks depletion period, rats had free access to the iron-deficient diet and deionized water until blood Hb concentration was below 6 g/dL. In the beginning of the repletion period, all rats were divided into five groups according to Hb concentration and body weight : iron-deficient diet (D), D plus 12 ppm Fe from Moringa leaves (12M), D plus 24 ppm Fe from Moringa leaves (24M), D plus 12 ppm Fe as FeSO4 form(12C), D plus 24 ppm Fe as FeSO4 form (24C). D and M groups were fed ad libitum. The C groups was pair-fed to the M groups. In the second week of depletion period, blood for monitoring Hb concentration was drawn from rat’s tails. The repletion period lasted for 5 weeks. Results showed the regenerated Hb concentrations and gains in total Hb and in Hb iron all increased as the increasing dose of iron supplementation either as FeSO4 or as Moringa leaves. Those iron associated parameters in D group had the lowest response. Taking FeSO4 as baseline, the RBV of iron from Moringa leaves are about 29~50%. Fe-deficient rats tended to increase the TG concentrations of serum. Both FeSO4 and Moringa fed rats significantly reduced the rising effect of hepatic TG content induced by iron deficiency. In summary, both Moringa leaves and FeSO4 can decrease the TG concentrations of serum and liver. Moringa leaves has good iron bioavailability than most plant foods. Moringa leaves rich in natural iron source provide an another choice for improving the poor iron nutritional status in developing countries.
