2 Industrial Plant Oil Extraction
79
These fatty acid compositions revealed in this study are similar to those reported by
Salimon et al. and Ogunniyi. Among them, ricinoleic acid (C 18 H 34 O 3 ) was the most
predominant fatty acid; it is a structurally cis-12-hydroxyoctadeca-9-enoic acid, 18carbon hydroxylated fatty acid having one double bond, which can be easily oxidated,
hydrogenated, and dehydrated, making it widely be used for industrial applications
like bio-lubricating oil and biodiesel with excellent viscosity and fluidity. There was
no significant difference (p > 0.05) in the amount of major fatty acids of the AEE
oil compared with SE. The same results were observed in Camellia, Pumpkin, and
Balanites aegyptiaca kernel oil. Suggesting AEE would not affect the fatty acid
composition of castor seed oil.
2.6.2.4 Scanning Electron Micrographs (SEM)
The castor seed kernels samples before and after extraction were fixed in the glutaraldehyde solution for 2 h and stored in −4 °C for 5 min; after ethanol dehydration
and vacuum desiccation, the samples were sputtered with a thin layer of carbon and
gold. The morphological alterations of these samples were observed with a JEM-1200
scanning electron microscope system (JEOL Company, Japan).
To gain a better understanding of the AEE mechanism of castor seeds oil, the
cell surface structure of castor seed kernel samples were investigated by SEM. As
shown in Fig. 2.8a, a smooth and intact cell surface was observed before extraction,
some protein bodies were released out due to the physical grounding pretreatment.
After aqueous extraction process (without addition of enzymes), more protein and
oil were diffused, but the external surface of seed tissues was still intact and smooth
(Fig. 2.8b). After enzymes were applied, the cell walls of seed tissue begin to rupture
(Fig. 2.8c). A significant destruction of the morphological structure of seed tissues
was observed as the extraction time increasing from 1 to 4 h, and most inner cells
were disorganized and broken (Fig. 2.8d).
2.6.2.5 Statistical Analysis
All the experiments were performed in triplicate whereas the statistical analysis of
the data was done by analysis of variance (ANOVA). A probability value at p <
0.05 was considered statistically significant. Mean separation among treatments was
conducted using Tukey’s honest significant difference (HSD) multiple comparison.
All statistical analyses were performed using JMP (version 12, SAS Institute Inc.,
Cary, NC).
Based on the results of mono-factor tests, the enzyme concentration from 2.5
to 3.5%, hydrolysis temperature from 45 to 55 °C, hydrolysis time from 4 to 6 h,
and ratios of material to water from 1:3 to 1:5 were selected for BBD (Table 2.13).
Moreover, the significance of each coefficient of the model was also determined
using the t test and p-value.
79
These fatty acid compositions revealed in this study are similar to those reported by
Salimon et al. and Ogunniyi. Among them, ricinoleic acid (C 18 H 34 O 3 ) was the most
predominant fatty acid; it is a structurally cis-12-hydroxyoctadeca-9-enoic acid, 18carbon hydroxylated fatty acid having one double bond, which can be easily oxidated,
hydrogenated, and dehydrated, making it widely be used for industrial applications
like bio-lubricating oil and biodiesel with excellent viscosity and fluidity. There was
no significant difference (p > 0.05) in the amount of major fatty acids of the AEE
oil compared with SE. The same results were observed in Camellia, Pumpkin, and
Balanites aegyptiaca kernel oil. Suggesting AEE would not affect the fatty acid
composition of castor seed oil.
2.6.2.4 Scanning Electron Micrographs (SEM)
The castor seed kernels samples before and after extraction were fixed in the glutaraldehyde solution for 2 h and stored in −4 °C for 5 min; after ethanol dehydration
and vacuum desiccation, the samples were sputtered with a thin layer of carbon and
gold. The morphological alterations of these samples were observed with a JEM-1200
scanning electron microscope system (JEOL Company, Japan).
To gain a better understanding of the AEE mechanism of castor seeds oil, the
cell surface structure of castor seed kernel samples were investigated by SEM. As
shown in Fig. 2.8a, a smooth and intact cell surface was observed before extraction,
some protein bodies were released out due to the physical grounding pretreatment.
After aqueous extraction process (without addition of enzymes), more protein and
oil were diffused, but the external surface of seed tissues was still intact and smooth
(Fig. 2.8b). After enzymes were applied, the cell walls of seed tissue begin to rupture
(Fig. 2.8c). A significant destruction of the morphological structure of seed tissues
was observed as the extraction time increasing from 1 to 4 h, and most inner cells
were disorganized and broken (Fig. 2.8d).
2.6.2.5 Statistical Analysis
All the experiments were performed in triplicate whereas the statistical analysis of
the data was done by analysis of variance (ANOVA). A probability value at p <
0.05 was considered statistically significant. Mean separation among treatments was
conducted using Tukey’s honest significant difference (HSD) multiple comparison.
All statistical analyses were performed using JMP (version 12, SAS Institute Inc.,
Cary, NC).
Based on the results of mono-factor tests, the enzyme concentration from 2.5
to 3.5%, hydrolysis temperature from 45 to 55 °C, hydrolysis time from 4 to 6 h,
and ratios of material to water from 1:3 to 1:5 were selected for BBD (Table 2.13).
Moreover, the significance of each coefficient of the model was also determined
using the t test and p-value.