Extraction and concentration of biogenic calcium oxalate from plant leaves

Abstract

SUMMARYThe objective of this study was to extract and concentrate calcium oxalate (CaOx) crystals from plant leaves that form the above mentioned crystals. The chemical and physical studies of CaOx from plant to be performed depend on an adequate amount of the crystals. The plant used in this study was croton (Codiaeum variegatum). The leaves were ground in a heavy duty blender and sieved through a 0.20 mm sieve. The suspension obtained was suspended in distilled water. The crystals were concentrated at the bottom of a test tube. The supernatant must be washed until it is free of plant pigments and other organic substances. Biogenic CaOx crystals have well-defined and sharp peaks, indicating very high crystallinity. Moreover, the CaOx crystals were not damaged during the extraction procedure, as can be seen on the scanning electron microscope images. The porposed method can be considered efficient to extract and concentrate biogenic calcium oxalate.Index terms: biogenic calcium oxalate, biomineral, extraction of calcium oxalate. RESUMO: EXTRAÇÃO E CONCENTRAÇÃO DE OXALATO DE CÁLCIO BIOGÊNICO DE FOLHAS DE PLANTASO objetivo deste estudo foi extrair e concentrar cristais de oxalato de cálcio (CaOx) a partir de folhas de plantas que formam os cristais mencionados. Os estudos químicos e físicos de CaOx de plantas a serem realizados demandam uma massa adequada dos cristais. A planta usada neste estudo foi o cróton (Codiaeum variegatum). As folhas foram trituradas por um liquidificador industrial e peneiradas em peneira de 0,20 mm. Ao suco obtido foi adicionada água destilada. Os cristais foram concentrados no fundo da proveta. É necessário manter a lavagem dos cristais até que o sobrenadante fique livre de pigmentos de plantas e outras substâncias orgânicas. Os cristais de CaOx apresentaram picos bem formados e estreitos, indicando que sua cristalinidade é muito alta; além disso, esses cristais não foram danificados durante o procedimento de extração, o que pode ser visto observando-se as fotos obtidas pelo microscópio eletrônico de varredura. O método apresentado pode ser considerado eficiente para extrair e concentrar cristais de oxalato de cálcio biogênico.Termos de indexação: oxalato de cálcio biogênico, biomineral , extração de oxalato de cálcio.

Biochar application to a contaminated soil reduces the availability and plant uptake of zinc, lead and cadmium

“…5), in both treatments. Despite the lack of evidence to substantiate some functional properties of CaOx, the participation of intra and extracellular calcium regulation in plant protection and detoxification of metal is quite evident (Costa et al, 2009). …”

Physico-chemical characteristics and thermal stability of calcium oxalate crystals isolated from Beta vulgaris root

“…Root tissues retained in the sieve was ground again with equal volume (v:w) of double distilled water and the juice was collected by filtration. The procedure was repeated until the plant juice becomes clear (da Costa et al, 2009). Juice was centrifuged at 6000 rpm for 30 min to separate calcium oxalate crystals with fine plant tissues.…”

“…Crystals in plants serve as structural supports for their growth, calcium oxalate crystals occur in many plants and in most organs and tissues (Franceschi and Horner, 1980;Holloway et al, 1987;Oscarsson et al, 2007). Calcium oxalate in plants are highly crystalline and are not damaged during extraction (da Costa et al, 2009).…”

Calcium oxalate biomineralization in plants

“…于被子 植物 , 50%的目属于双子 叶植物 [4,6~8,10,24~60] , 说明草酸钙晶体在植物界中分布广泛, 主要存在于 维 管 束 植 物 中 (图 1). 草 酸 钙 主 要 沉 积 部 位 分 布 在 叶片、茎、种子、苞片、花药、根等器官中的晶异细 胞 中 [8,58,62] , 另 外 还 可 形 成 在 特 定 的 组 织 或 细 胞 类 型中, 如通气组织和石细胞 [9] . 草酸钙晶体与淀粉 体、叶绿体和其他细胞质组分沿细胞骨架以一定速 度移动, 表明草酸钙晶体也存在于细胞质中 [24] .…”