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Genetic engineering of artemisinin biosynthesis: prospects to improve its production

100%

Abdin N. Z. , Alam P.

Acta Physiologiae Plantarum

2015

tom 37

nr 02

Artemisinin, a potent antimalarial natural compound, is obtained from aerial parts of Artemisia annua L. plants. The demand (101–119 MT) for artemisinin is exponentially increasing every year because of increased incidence of drug-resistant malaria throughout the world, especially in Africa and Asia. However, the presence of low concentrations (0.01–1.1 %) of the compound in A. annua L. plants poses a major constraint in the commercialization of artemisinin-based combination therapies (ACTs) recommended by WHO for the treatment of multidrug- resistant and cerebral malaria. Further, the improvement in the yield of artemisinin through conventional breeding, in vitro culture, cell suspension culture and total organic synthesis still poses a challenge. However, possibilities are there to enhance the artemisinin biosynthesis either by overexpression of the genes encoding enzymes associated with the rate-limiting steps of the mevalonate and artemisinin biosynthetic pathways or by the suppression of genes encoding enzymes of other competing pathways. Based on the current understanding of the pathway and cloning of the related genes, efforts have been made for the past few years to increase the artemisinin content in A. annua L., Cichorium intybus L. and microbes through metabolic engineering. In the present review, we have discussed the metabolic engineering strategies in both plant and microbial systems for artemisinin accumulation in bioengineered hosts.

Matrix solid-phase dispersion method coupled with high-performance liquid chromatography for the simultaneous quantification of selected compounds from freeze dry pomegranate juice

80%

Kamal Y. T. , Yusufoglu H. , Alam P. , Fouda A.

Acta Chromatographica

2018

tom Vol. 30, no. 3

153--157

In this research, a novel method was developed for the matrix solid phase dispersion (MSPD) followed by high-performance liquid chromatography (HPLC) quantification of four marker constituents (vitamin C, gallic acid, rutin, and ellagic acid) in the freeze-dried pomegranate fruit juice. Various MSPD parameters like type of dispersant, sample–dispersant ratio, solvents, its volume, and time of extraction have been optimized after many trials. Furthermore, HPLC method has been developed and optimized for the analysis of all four components. The HPLC separation was achieved using a 250 × 4.6 mm column, particle size of 5 μm, C18 reverse phase column, with a mobile phase consisting of acetonitrile and 0.05% H3PO4, in gradient elution mode with a mobile phase flow rate of 1 mL/min, using ultraviolet (UV)–visible detection at 254 nm. All calibration curves showed good linear regression (r2 ≥ 0.9925) within test ranges. The extraction recoveries of the marker constituents analyzed by MSPD methods were found as ranging from 97.5% to 103.5%. From comparing the chromatograms, validation data and other parameters like time, labor, and feasibility, we found that MSPD technique was most suitable for the analysis as compared to conventional liquid–liquid extraction technique.

Densitometric HPTLC analysis of cordifolioside A in Tinospora cordifolia and commercial formulations

80%

Alam P. , Ali M. , Singh R. , Shakeel F.

Acta Chromatographica

2009

tom Vol. 21, no. 4

683--692

A densitometric HPTLC method for analysis of cordifolioside A both in 60% methanolic extract of Tinospora cordifolia and in a commercial formulation has been established and validated. Cordifolioside A was separated on aluminum-backed silica gel 60 F254 plates with chloroform-methanol 85:15 (%, v/v ) as mobile phase. A compact band was obtained for cordifolioside A at R F 0.52 ± 0.03. The limits of detection (LOD) and quantification (LOQ) were 20.12 and 60.36 ng per band, respectively. The highly precise and accurate method was used for analysis of cordifolioside A.