DNA Barcode ITS Effectively Distinguishes the Medicinal Plant Boerhavia diffusa from Its Adulterants

Boerhavia diffusa (B. diffusa), also known as Punarnava, is an indigenous plant in India and an important component in traditional Indian medicine. The accurate identification and collection of this medicinal herb is vital to enhance the drug’s efficacy and biosafety. In this study, a DNA barcoding technique has been applied to identify and distinguish B. diffusa from its closely-related species. The phylogenetic analysis was carried out for the four species of Boerhavia using barcode candidates including nuclear ribosomal DNA regions ITS, ITS1, ITS2 and the chloroplast plastid gene psbA-trnH. Sequence alignment revealed 26% polymorphic sites in ITS, 30% in ITS1, 16% in ITS2 and 6% in psbA-trnH, respectively. Additionally, a phylogenetic tree was constructed for 15 species using ITS sequences which clearly distinguished B. diffusa from the other species. The ITS1 demonstrates a higher transition/transversion ratio, percentage of variation and pairwise distance which differentiate B. diffusa from other species of Boerhavia. Our study revealed that ITS and ITS1 could be used as potential candidate regions for identifying B. diffusa and for authenticating its herbal products.     

FLOWER CULTURE OF A MALE STERILE STAMENLESS-2 MUTANT OF TOMATO (LYCOPERSICON ESCULENTUM)

Young floral buds of a male sterile stamenless-2 (sl-2/sl-2) mutant of tomato were cultured, at the sepal primordia stage, in a liquid Murashige and Skoog medium containing either benzylaminopurine (BAP) or gibberellic acid (GA₃) or both. In the basal medium (BM), the buds initiated petal and stamen primordia only and they showed limited development. In buds grown in BM supplemented with 10^–6 M BAP, all types of organ primordia were initiated but the petals remained small and the stamens and carpels were immature. Well-developed flowers with a normal complement of floral organs were, however, produced in a medium containing both BAP (10^–6 M) and GA₃ (10^–7 M to 10^–5 M). The development of stamens was variable and ranged from the complete absence of microsporogenesis to the formation of abnormal pollen. Gynoecium development was normal and ovules with megaspores were produced in the ovary. The results show that male sterility in the sl-2/sl-2 mutant can be expressed in vitro and that GA₃ is essential for the in vitro growth and development of all the floral organs of this mutant.     

Electrochemical determination of antihypertensive drug irbesartan in pharmaceuticals

A sensitive voltammetric method has been developed for the determination of irbesartan in a Britton–Robinson buffer medium. Irbesartan exhibited a well-defined cathodic peak over the entire pH range from 2.0 to 12.0. The mechanism of reduction was postulated on the basis of controlled potential electrolysis, coulometry, and spectral analysis. Under optimal conditions, a linear response of irbesartan was obtained in the range from 3.0 × 10⁻⁵ to 5.7 × 10⁻³ mol L⁻¹ and with a limit of detection of 5.33 × 10⁻⁷ mol L⁻¹. The effect of cationic surfactant on the voltammetric reduction peak of irbesartan in Britton–Robinson buffer is also described.     

Safety Assessment of Potential Probiotic Lactobacillus fermentum MTCC-5898 in Murine Model after Repetitive Dose for 28 Days (Sub-Acute Exposure)

Safety assessment of probiotic Lactobacillus fermentum MTCC-5898 (LF) with three doses (10⁷, 10⁹, and 10¹¹ cfu/day/animal) was carried on Swiss albino mouse weanlings for 28 days using oral route. Health status of animals was monitored by physical assessment of body weight, organ indices, and histological appearances of liver and intestine along with measurement of hematological parameters (Hb, WBC, RBC count, MCHC, MCV, MCH), biochemical analytes in blood involving glucose, serum enzymes (ALT, AST and LDH), urea, creatinine, and lipid profile (total cholesterol, triglycerides, HDL, VLDL, LDL, and atherogenic index). LF showed no adverse effects on above parameters of general health status after continuous consumption for the experimental period. On the other hand, significant increase (p ≤ 0.05) in TGF-β (regulatory cytokine) and considerable decrease (p ≤ 0.05) in IFN-γ (pro-inflammatory cytokine) without any major changes in IL-4 and IL-12 in intestinal fluid on consumption of 10⁹ cfu/animal/day confirmed its dose-specific response for immune homeostasis. Further, safety of LF was also confirmed by insignificant changes in release of FITC-dextran (4 kDa) in blood on its consumption than control group where only saline was given orally. Moreover, significantly (p ≤ 0.05) increased mRNA expression of claudin-1 and MUC-2 in intestinal epithelial cells on feeding L. fermentum further supported FITC-dextran permeability data which otherwise showed increased flux of FITC-dextran in blood on consumption of E. coli (10⁹ cfu/animal/day) due to intestinal damage. Thus, in vivo results confirmed that Lactobacillus fermentum MTCC 5898 is safe and non-toxic to weanling mice and may be considered for functional food application after clinical testing.

     

Formation of a G-quadruplex at the BCL2 major breakpoint region of the t(14;18) translocation in follicular lymphoma

The t(14;18) translocation in follicular lymphoma is one of the most common chromosomal translocations. Most breaks on chromosome 18 are located at the 3'-UTR of the BCL2 gene and are mainly clustered in the major breakpoint region (MBR). Recently, we found that the BCL2 MBR has a non-B DNA character in genomic DNA. Here, we show that single-stranded DNA modeled from the template strand of the BCL2 MBR, forms secondary structures that migrate faster on native PAGE in the presence of potassium, due to the formation of intramolecular G-quadruplexes. Circular dichroism shows evidence for a parallel orientation for G-quadruplex structures in the template strand of the BCL2 MBR. Mutagenesis and the DMS modification assay confirm the presence of three guanine tetrads in the structure. 1H nuclear magnetic resonance studies further confirm the formation of an intramolecular G-quadruplex and a representative model has been built based on all of the experimental evidence. We also provide data consistent with the possible formation of a G-quadruplex structure at the BCL2 MBR within mammalian cells. In summary, these important features could contribute to the single-stranded character at the BCL2 MBR, thereby contributing to chromosomal fragility.