Nchimbi Hamisi Yunus
College of Natural and Mathematical Sciences, University of Dodoma (UDOM), P. O. Box 259, Dodoma, Tanzania.
Heliyon. 2021 Mar 8;7(3):e06397. doi: 10.1016/j.heliyon.2021.e06397. eCollection 2021 Mar.
Due to the worldwide increase in the demands for bioenergy sources to replace fossil fuels. oil produced by stems and modified leaves (phylloclades) is a valuable liquid fuel as an alternative energy source for biofuel production. In this study, oils were extracted from stem barks with varying stem girths (20cm-80cm) and fully grown apical phylloclades. Soxhlet apparatus was used in oil extraction according to Luque de Castro and García (2000). The percentage (%) oil yield was calculated by the weight of extracted oil to the total weight of the dried sample (20g). The study hypothesized that significantly higher oil yields would be obtained from larger stem girths than phylloclades of the same trees in different Agro-Ecological Zones (AEZs). Likewise, the difference in oil yields was higher in the Semi-arid AEZ than in the Southern highland and the Coast AEZs (p > 0.05). Results showed slightly higher oil yields from large stem girths [16.47% ± 0.34%/(20g) max ≡ 82.35% ± 0.34%/(100g) max] than phylloclades [15.7% ± 0.49%/(20g) max ≡ 78.5% ± 0.34%/(100gmax] in different AEZs. Oil yields from Semi-arid [82.35% ± 0.34%/(100g) max and 78.5% ± 0.49%/(100g) max] were slightly higher than Southern highland [79.0% ± 0.34%/(100g) max and 76.4% ± 0.49%/(100g) max] and the Coast [76.4% ± 0.34%/(100g) max and 70.25% ± 0.49%/(100g) max] AEZ. But the difference in oil yields was not significant (p > 0.05). Results exhibited increasing patterns in the percentage (%) oil yields from low (20cm) to larger (80cm) stem girths. High oil yields between stem girths (82.35%) and phylloclades (78.5%) suggest that oil is suitable for liquid biofuel production as an energy source in Tanzania.
由于全球对生物能源的需求不断增加以取代化石燃料，茎和改良叶（叶状枝）产生的油作为生物燃料生产的替代能源是一种有价值的液体燃料。在本研究中，从不同茎围（20厘米至80厘米）的茎皮和完全成熟的顶端叶状枝中提取油。根据卢克·德·卡斯特罗和加西亚（2000年）的方法，使用索氏提取器进行油的提取。出油率（%）通过提取油的重量与干燥样品总重量（20克）计算得出。该研究假设，在不同农业生态区（AEZs），相同树木较大茎围的出油率会显著高于叶状枝。同样，半干旱农业生态区的出油率差异高于南部高地和海岸农业生态区（p>0.05）。结果表明，在不同农业生态区，较大茎围的出油率[16.47%±0.34%/（20克）最大值≡82.35%±0.34%/（100克）最大值]略高于叶状枝[15.7%±0.49%/（20克）最大值≡78.5%±0.34%/（100克）最大值]。半干旱地区的出油率[82.35%±0.34%/（100克）最大值和78.5%±0.49%/（100克）最大值]略高于南部高地[79.0%±0.34%/（100克）最大值和76.4%±0.49%/（100克）最大值]以及海岸地区[76.4%±0.34%/（100克）最大值和70.25%±0.49%/（100克）最大值]农业生态区。但出油率差异不显著（p>0.05）。结果显示，出油率（%）从低茎围（20厘米）到较大茎围（80厘米）呈增加趋势。茎围（82.35%）和叶状枝（78.5%）之间的高出油率表明，在坦桑尼亚，这种油作为能源适合用于液体生物燃料生产。
