Evaluation of Scaling Inhibiting Compounds in Cajanus cajan and Vigna subterranea Shell Extracts for Industrial Utilization

Abstract

The objective of this paper is to evaluate and present the scaling inhibiting compounds of aqueous and methanolic extracts obtained from cajanus cajan (c. cajan) and vigna subterranean (v.subterranea) shells collected from Nsukka, Enugu State, Nigeria using appropriate standard techniques.  Quantitative phytochemical analysis (expressed in mg/100g) revealed the following secondary metabolites for C. cajan: flavonoids (2226.50± 47.35), phenolics (6294.65±117.35), saponins (2.53±0.15), alkaloids (587.42±42.3), steroids (0.77±0.02), terpenoids (989.87±26.72), and tannins (176.49±13.18). Similarly, V. subterranean exhibited; flavonoids (2226.50± 47.35), phenolics (6400.11±65.22), saponins (1.79±0.4), alkaloids (114.22±17.64), steroids (0.46± 0.06), terpenoids (308.94±10.22), and tannins (58.18±1.12). GC-MS analysis of both C. cajan and V. subterranean extracts revealed 14 peaks of different compounds which includes; phenol, methylphenol, dimethylphenol, 2-furaldehyde, 2-hydroxymethifuran, levoglucosan, 4-mehtylguaiacol, vinylphenol, 4-vinylguaiacol, eugenol, vanillin, isoeugenol, 4-allyl-2-6dimethoxphenol and dimethylbenzene. Additionally, FT-IR spectra identified functional groups such as O-H (phenolics) at 3438 and 3430, CH₂ stretching aliphatic at 2923 and 2884, and C=C unsaturated at 1635 and 1643, present in both extracts. The results from GC-MS, FT-IR, and phytochemical studies collectively suggest that these extracts contain environmentally friendly constituents, particularly higher concentrations of phenolic and foaming agents. This supports the potential of C. cajan and V. subterranean as candidates to be deployed as environmentally friendly scale inhibitors.