The principles of effective antimicrobial treatment Essay

The varied response of microorganisms to biocides may be ascribed to variations in morphological structure (e.g. vegetative cell versus mature spore) and chemical composition of the individual microorganism (Maillard, 2002 Turner et al., 2000). Addition of chemical preservatives to the holding solution is recommended to prolong the vaselife of cut flowers. All holding solutions must essentially contain two components viz., sugar and germicides. The sugars provide a respiratory substrate, while the germicides control harmful bacteria and prevent plugging of the conducting tissues. Therefore, developing proper techniques to prolong the vaselife of cut flowers will be a great asset to the growers and users. To be effective, an antimicrobial treatment must function in all conditions, including across varying vase solution composition (Knee, 2000), and against the prevalent microorganism, such as a specific bacterial and fungal species (Turner et al., 2000).

The principle antimicrobial compounds that have been used to extend the vase life of cut flowers are hydroxyquinoline (HQ) compounds, such as 8hydroxyquinoline citrate (HQC) (Knee, 2000) and 8hydroxyquinoline sulphate (HQS) (Hussein, 1994) as well as silver compounds, such as silver nitrate (AgNO3) (Fujino et al., 1983). 8HQ, which is broadly used, is very expensive and most harmful preservative for humans causing irritation to skin, eyes and respiratory tract. Nowadays, some of the chemical compounds, such as silver nitrate and silver thiosulfate are less applied because they cause blacking of the flower stem and are dangerous from human health and environment perspective (Damunupola and Joyce, 2008). Therefore, researchers tend to identify new, safe and less toxic materials for preservation and increment of the vase life of cut flowers (Shimamura et al., 1997).

The safe alternatives are the natural chemical compounds like herbal extracts and essential oils extracted from aromatic and medicinal plants. Herbal extracts and essential oils have been used for long for different purposes. The most emphasized subject is antimicrobial characteristics. Although the preservative nature of some plant extracts has been known for centuries, the antimicrobial properties of extracts of aromatic plants have received renewed attention for only a decade or so.

In recent times, the search for potent antimicrobial agents has been shifted to plants. Due to increased resistance of many microorganisms towards established antibiotics, investigation of the chemical compounds within traditional plants has become desirable. Most plants are medicinally useful in treating disease in the body and in most of cases the antimicrobial efficacy value attributed to some plants is beyond belief.

The beneficial medicinal effects of plant materials typically result from the combinations of secondary metabolites such as alkaloids, steroids, tannins, and phenol compounds, flavonoids, resins fatty acids gums which are capable of producing definite physiological action on body (Joshi et al., 2009).

Plantbased antimicrobials remain a vast untapped source for medicines with enormous therapeutic potential. They are effective against many infectious microorganisms, while simultaneously mitigating many of the side effects that are often associated with synthetic antimicrobials. The important advantages of medicinal plants are their safety besides being economical, effective and their easy availability (Siddiqui, 1993).