The Safety Assessment of Toxic Metals in Commonly Used Pharmaceutical Herbal Products and Traditional Herbs for Infants in Jordanian Market

The objective of this study was to assess the levels of contamination by toxic metals (Pb, Al, Ni, Cd and As) that may be present in 25 infant pharmaceutical herbal products and 15 traditional herbs in Jordan. Both products and medicinal herbs are currently prescribed by paediatricians. They are available as over-the-counter medicines and are sold the in herbal market, ensuring easy accessibility for parents. Inductively coupled plasma-optical emission spectroscopy (ICP-OES), with limit of detections (LODs) of 0.10, 1.00, 0.20, 0.15 and 2.00 mg.kg⁻¹ for Pb, Al, Ni, Cd and As respectively, was employed to measure the levels of toxic metals in the samples. Pb, Al and Ni were detected in 88, 76 and 4% of the analysed samples of pharmaceutical herbal products and in 93, 87 and 13% of the analysed samples of traditional herbs, respectively. Neither Cd or As were detected in all analysed samples. The data obtained were subsequently compared by referral to the acceptable limits of toxic heavy metals according to World Health Organisation (WHO) standards. Largely, the results showed acceptable toxic metal levels in the finished pharmaceutical products and the traditional medicinal herbs for infants. One exception to this was Persian Thyme (Satureja thymbra) with Pb content of 41.18 mg.kg⁻¹. Also, the daily intake of detected metals through pharmaceutical herbal products was found to be lower than the daily tolerable intake limit set by the regulatory bodies, except of 8% of products that exceeded the tolerable daily intake of Pb set by US FDA, as compared to traditional medicinal herbs, where the tolerable daily intake for Pb, Al and Ni were exceeded in 40, 60 and 8% of the analysed herbs, respectively. The results obtained revealed that the excessive use of medicinal plants as alternative medicine should be used with caution keeping in mind the safety factor in infants.

     

Biochemical Characterization,Molecular Cloning,and Structural Modeling of an Interesting β-1,4-Glucanase from Sclerotinia Sclerotiorum

The filamentous fungus Sclerotinia sclerotiorum produces a complete set of cellulolytic enzymes needed for efficient solubilization of native cellulose, the major component of plants. In this work, we reported the molecular characterization of an important glycosyl-hydrolase enzyme classified as endo-β-1,4-glucanase. The importance of this enzyme was revealed with the in-gel activity staining, showing a high degradation capacity of cellulose. When purified from native gel and ran in denaturing polyacrylamide gel, the polypeptide has an apparent molecular mass of about 34 kDa called Endo2. For further characterization of this protein, a mass spectrometry approach was carried out. The LC–MS/MS analysis revealed two peptides belonging to this enzyme. The genomic DNA and cDNA sequences were resolved by PCR amplification and sequencing, revealing a gene with two intron sequences. The open reading frame of 987 bp encoded a putative polypeptide of 328 amino acids having a calculated molecular mass of 33,297 Da. Yet, the molecular modeling and comparative investigation of different 3D cellulase structures showed that this endoglucanase isoform has probably two domains. A core domain having a high similarity with endoglucanases family 5 and a cellulose-binding domain having similarities with those of exo-type cellulases of family 1, linked together by a serine-threonine-rich region. These results are with great interests and show new characteristics of S. sclerotiorum glucanase.