Abstract
Carrageenan (car-) are comprised of linear sulfated polysaccharides family isolated from the species of Rhodophyta (Patel 2012; Shukla et al. 2016). These polysaccharides and their derivatives have been exploited in cosmetics, food, and pharmaceuticals. Another beneficial activity of the car- has been further explored in the drug delivery system as a controlled release agent that possesses antioxidant properties as well (Genicot et al. 2018; Li et al. 2014). There are three variants of the car- i.e. lambda, kappa, iota, and among them κ- possess a peculiar range of properties such as biocompatibility, biodegradability, mechanical strength, and hydrophilicity exploited in the food industry as a stabilizing and thickening agent (Derkach et al. 2018; Ghanbarzadeh, Golmoradizadeh, and Homaei 2018; Sahiner, Sagbas, and Yılmaz 2017). Car- films in combination with glycerol and citric acid further ameliorate the anti-microbial activity (Khare et al. 2016; Sedayu, Cran, and Bigger 2019). While reliable bioassays are needed to recognize a wide range of pharmacological properties present in plants and their corresponding metal complexes. Chromium (Cr3+) is a toxic metal and carcinogenic but its complexation with few ligands proves them to be a potential therapeutic agent. Cr3+ complexes with amino acid derivatives showed antimicrobial activity against different bacterial species. Antibiotics with ceftriaxone with metal complexes showed good antimicrobial properties. The complex of metals with 4-hydroxypyridine and azide ion Zn2+ complex with tridentate ligand showed low antibacterial but high antifungal properties.
The movement of Cr3+ in living organisms depends considerably on the complexation of the metal center by chelating nitrogen donor ligands. Cr3+ cysteine and hydrazide complexes, on the other hand, have noticeable antibacterial and antifungal activities. Sulfonamides, Sulfanilamide derivatives, and cephapirin with Cr3+ complexes showed good antimicrobial properties. Monoamine oxidase-B inhibition by Cr3+ triethanolamine complexes leads to the prevention of some neurodegenerative diseases.
The activities of compounds obtained from plants and their metal complexes can be detected by the same conventional methods based on the same principle and are not equally efficient and sensitive. It is clear that biological evaluation, in general, can be carried out much more proficiently on water-soluble, nice crystalline complexes than on mixtures like plant exudate (Zaidi et al. 2012). However, the antibacterial activities of Cr3+ with κ, to the best of our knowledge, have not been reported yet.
Previously, we had studied the preparation and antimicrobial activity of nicotine and its Zn2+ complex. However, minimum inhibitory concentration (MIC) was the basis for the evaluation of the antibacterial activity. In this study, the complexed κ- in-vitro activity was evaluated against different types of pathogenic gram-negative and gram-positive bacteria.