Quality control of certain slimming herbal products present in the Egyptian market

Abstract

Two commercial slimming herbal tea products present in the Egyptian market viz; Sekem Herbal Tea (commercial herbal tea-1) and Royal Regime Tea (commercial herbal tea-2) were quality-evaluated compared to two prepared standard mixtures; prepared standard herbal tea-1, composed of mixture of herbs of Sekem Herbal Tea (chicory, marjoram, nettle and senna leaves, liquorices roots, celery fruits and calendula flowers) and prepared standard herbal Tea-2 composed of mixture of herbs of Royal Regime Tea (fennel, senna and chicory). Quality control of both commercial and prepared herbal teas was conducted through microscopical identification of their diagnostic elements, determination of certain heavy metals and pharmacopeial constants and detection of aflatoxins content and total microbial count. Quality control was also conducted through HPLC quantitative estimation of main active constituents of the commercial and prepared standard herbal teas, where results revealed that as for the percentages of sennoside A in commercial herbal tea-1 and its standard tea were 58.87 and 56.70, respectively, while its percentage in commercial herbal tea-2 and its standard tea were 59.30 and 55.17, respectively, as for esculetin percentages in commercial herbal tea-1 and its standard tea were 0.41 and 0.73, respectively, while its percentages in commercial herbal tea-2 and its standard tea was the same 0.17 and as for scopoletin percentage in commercial herbal tea-1 and its standard tea were 0.19 and 0.18, respectively, which all within the reported standard limits. Quality control was also conducted through GC/MS of the volatile oil constituents, the percentage yields of volatile oils, which were obtained by hydrodistillation of both commercial tea-1 and its corresponding standards tea were 1.8 and 2.0 V/W, respectively, while that of commercial tea-2 and its corresponding standard tea were 2.0 and 2.2 V/W, respectively. GC-MS analysis revealed that the major oil components of both commercial teas and their corresponding prepared standard teas were nearly the same with slight significant different percentages. Lipid profile tests (cholesterol, triglycerides and total lipids) were carried out in induced hypercholesteremic rats and after eight weeks of oral treatment with aqueous extracts of commercial teas-1 and -2 and their standard teas, showing significant reduction in cholesterol, triglycerides and total lipids plasma levels. Sekem herbal tea decreased the glucose levels by 10.7% in normoglycemic rats after 30 minutes of glucose oral administration and by 8.3% in STZinduced diabetic rats after 30 days treatment; while it's prepared standard tea caused 5.7 and 4.5% reduction, respectively. Royal Regime Tea decreased the glucose levels in normoglycemic and hyperglycemic rats by 3.0 and 6.0% reduction, respectively; while it's prepared standard tea decreased the blood glucose level by 9.6 and 8.3% in normoglycemic and hyperglycemic rats after 30 minutes and 30 days of treatment, respectively.