Anatomical structure of Camellia oleifera shell
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The main product of Camellia oleifera is edible oil made from the seeds, but huge quantities of agro-waste are produced in the form of shells. The primary components of C. oleifera fruit shell are cellulose, hemicellulose, and lignin, which probably make it a good eco-friendly non-wood material. Understanding the structure of the shell is however a prerequisite to making full use of it. The anatomical structure of C. oleifera fruit shells was investigated from macroscopic to ultrastructural scale by stereoscopic, optical, and scanning electron microscopy. The main cell morphology in the different parts of the shell was observed and measured using the tissue segregation method. The density of the cross section of the shell was also obtained using an X-ray CT scanner to check the change in texture. The C. oleifera fruit pericarp was made up of exocarp, mesocarp, and endocarp. The main types of exocarp cells were stone cells, spiral vessels, and parenchyma cells. The mesocarp accounted for most of the shell and consisted of parenchyma, tracheids, and some stone cells. The endocarp was basically made up of cells with a thickened cell wall that were modified tracheid or parenchyma cells with secondary wall thickening. The most important ultrastructure in these cells was the pits in the cell wall of stone and vessel cells that give the shell a conducting, mechanical, and protective role. The density of the shell gradually decreased from exocarp to endocarp. Tracheid cells are one of the main cell types in the shell, but their low slenderness (length to width) ratio makes them unsuitable for the manufacture of paper. Further research should be conducted on composite shell-plastic panels (or other reinforced materials) to make better use of this agro-waste.
KeywordsCamellia oleifera shell Anatomical structure Exocarp Mesocarp Endocarp
Conceived and designed the experiments: JH, YL, SC; Performed the experiments: JH, YS, SC; Analyzed the data: JH, YS, YL, SC; Wrote the paper: JH, YS, SC. All authors contributed to preparing the manuscript. All authors read and approved the final manuscript.
This work was financially supported by the Hunan Provincial Natural Science Foundation of China (2017JJ1038), Opening Project of National Engineering Research Center for Oil-tea Camellia (2014CY02) in China.
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The authors declare that they have no conflict of interest.
- Agnihotri S, Dutt D, Tyagi CH (2010) Complete characterization of bagasse of early species of Saccharum officinerum-Co 89003 for pulp and paper making. BioResources 5:1197–1214Google Scholar
- Cao HJ (1992) Botany. Second Edition, China Forestry Publishing House, BeijingGoogle Scholar
- Lan F, Cui Y, Su ZH, Li ZM, Xie S (2012) Design and test on shelling and sorting machine of camellia oleifera fruit (in Chinese with summary in English). Transactions of the Chinese Society of. Agric Eng 28:33–39Google Scholar
- Panwar V (2001) Best available technology for 300 TPD bleached hardwood pulp of brightness 90 percent. A project report. University of Roorkee, Roorkee, pp 4–6Google Scholar
- Peng KY, Hu JB, Chen GH, Hu KF, Ma XW (2016) Research of chemical composition and combustion performance of Camellia oleifera fruit shells (in Chinese with summary in English). J Cent South Univ Forestry Techn 36:123–128Google Scholar
- Shen JF, Jiang TJ (2006) Nutritional value and health care function of camellia seed oil (in Chinese with summary in English). Cereal F Ind 13:6–8Google Scholar
- Zobel B, Webb C, Henson F (1959) Core or juvenile wood of loblolly and slash pine trees. Tappi Journal 42:345–356Google Scholar