**7. Genes that contributes in production of ergastic crystals**

Even though the nature of control of crystal shape and composition phenomena is yet fully unknown the taxonomic value of crystal shape assumes that it is under genetic control. The scanty knowledge about the mechanisms regulating production and crystal formation is another reason to establish the genetic contribution. Leaves from a chemically mutagenized *Medicago truncatula* population were visually screened for alterations in calcium oxalate crystal formation was performed by Nakata and Mc Conn and seven different classes of calcium oxalate defective mutants were identified. Genetic analysis suggested that crystal formation is a complex process involving more than seven loci [52]. Oxalate-producing plants, which include many crop plants, accumulate oxalate in the range of 3–80% (w/w) of their dry weight [25].

shoot [19]. So the presence of ergastic crystals from various plant parts, its size and structure is an important taxonomic key for the making difference between medicinally important

Ergastic Crystal Studies for Raw Drug Analysis http://dx.doi.org/10.5772/intechopen.74278 37

Land resources are blessed with numerable plants, which are of multifarious use. The combined effect of plant introduction and cultivation has largely accelerated the interest of scientists and industrialists to focus on herbal medicine and other economic products. For the sake of consumption of various plants with diverse phyto combinations processing of various level is suggestive. Even though modern biotechnological methods for analyzing and ensuring standards for stabilizing ergastic crystal concentration in raw, prepared food and herbal medicine is not available; traditional methods such as heating, boiling, frying, baking, battering, mashing, fermentation and sun drying, likely work by neutralization of cysteine proteases or through release of raphides from idioblasts or both. Neutralization of calcium oxalate from the dietary compounds still remains a bigger health question than the neutralization of specific crystal form of raphides. A traditional approach of avoiding plant pericarp rich in calcium oxalate and multilayered skin with lignified walls has beneficial effects. Discovery of fungi and bacteria that can break down calcium oxalate and plant genes that regulate calcium oxalate formation and crystallization have offered hope to

species *Costus pictus* and *Costus speciosus.*

counteract calcium oxalate toxicity.

Thara K. Simon and Justin R. Nayagam\*

University, Kottayam), Kerala, India

\*Address all correspondence to: justinr@uccollege.edu.in

Pune: Nirali Prakashan Publishers; 2010

[2] Esau K. Plant Anatomy. Fifth edition. Wiley Eastern Reprint. 1985

[3] Fahn A. Plant Anatomy. Oxford, New York: Pergamon Press; 1990

Department of Botany, Union Christian College, Aluva (Affiliated to Mahatma Gandhi

[1] Kokate CK, Purohit AP, Gokhale SB. Pharmacognosy. 46th ed. Vols. I & II. Shivaji Nagar,

[4] Coté GG. Diversity and distribution of idioblasts producing calcium oxalate crystals in *Dieffenbachia seguine* (Araceae). American Journal of Botany. 2009;**96**:1245-1254

**Author details**

**References**

**9. Conclusion**

Of the several metabolic pathways proposed, cleavage of ascorbic acid appears to be the most appreciable [53]. According to this view, once produced the oxalate combines with calcium to generate variety of crystal shapes and sizes. Further studies are required to identify the pathway(s) of oxalate production and calcium oxalate crystal formation.

A genetic approach would circumvent such technical limitations (e.g. idioblast number) and is a proven complement of biochemical and cellular investigations. Although the specific genes that have been altered are not yet to be identified it is understood that the control of crystal morphology is complex and under strict genetic control. As suggested by studies in other systems, mutations affecting protein, lipid, or polysaccharide function could contribute to alterations in crystal size or shape. Roles in ion balance (e.g. calcium regulation), in tissue support, in plant defense, in light gathering and reflection, and in detoxification have all been proposed [30]. Calcium oxalate crystals rapidly increase in size and number as the concentration of calcium in the plant environment is increased [54].

Nutritional studies have shown that oxalate is an anti-nutrient that sequesters calcium in a state that renders it unavailable for nutritional absorption by humans. Even though increasing nutritional quality by biotechnological method is fast in progress attempts to reduce or nullify the amount or effect of potential anti-nutritional agents from the economically useful plants is important.
