Noor Azmi Shaharuddin

Antiartherosclerotic effects of plant flavonoids.

Atherosclerosis is the process of hardening and narrowing the arteries. Atherosclerosis is generally associated with cardiovascular diseases such as strokes, heart attacks, and peripheral vascular diseases. Since the usage of the synthetic drug, statins, leads to various side effects, the plants flavonoids with antiartherosclerotic activity gained much attention and were proven to reduce the risk of atherosclerosis in vitro and in vivo based on different animal models. The flavonoids compounds also exhibit lipid lowering effects and anti-inflammatory and antiatherogenic properties. The future development of flavonoids-based drugs is believed to provide significant effects on atherosclerosis and its related diseases. This paper discusses the antiatherosclerotic effects of selected plant flavonoids such as quercetin, kaempferol, myricetin, rutin, naringenin, catechin, fisetin, and gossypetin.

HMG-CoA reductase inhibitory activity and phytocomponent investigation of Basella alba leaf extract as a treatment for hypercholesterolemia.

The enzyme 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase is the key enzyme of the mevalonate pathway that produces cholesterol. Inhibition of HMG-CoA reductase reduces cholesterol biosynthesis in the liver. Synthetic drugs, statins, are commonly used for the treatment of hypercholesterolemia. Due to the side effects of statins, natural HMG-CoA reductase inhibitors of plant origin are needed. In this study, 25 medicinal plant methanol extracts were screened for anti-HMG-CoA reductase activity. Basella alba leaf extract showed the highest inhibitory effect at about 74%. Thus, B. alba was examined in order to investigate its phytochemical components. Gas chromatography with tandem mass spectrometry and reversed phase high-performance liquid chromatography analysis revealed the presence of phenol 2,6-bis(1,1-dimethylethyl), 1-heptatriacotanol, oleic acid, eicosyl ester, naringin, apigenin, luteolin, ascorbic acid, and α-tocopherol, which have been reported to possess antihypercholesterolemic effects. Further investigation of in vivo models should be performed in order to confirm its potential as an alternative treatment for hypercholesterolemia and related cardiovascular diseases.

Functional characterization of sesquiterpene synthase from polygonum minus

Polygonum minus is an aromatic plant, which contains high abundance of terpenoids, especially the sesquiterpenes C15H24. Sesquiterpenes were believed to contribute to the many useful biological properties in plants. This study aimed to functionally characterize a full length sesquiterpene synthase gene from P. minus. P. minus sesquiterpene synthase (PmSTS) has a complete open reading frame (ORF) of 1689 base pairs encoding a 562 amino acid protein. Similar to other sesquiterpene synthases, PmSTS has two large domains: the N-terminal domain and the C-terminal metal-binding domain. It also consists of three conserved motifs: the DDXXD, NSE/DTE, and RXR. A three-dimensional protein model for PmSTS built clearly distinguished the two main domains, where conserved motifs were highlighted. We also constructed a phylogenetic tree, which showed that PmSTS belongs to the angiosperm sesquiterpene synthase subfamily Tps-a. To examine the function of PmSTS, we expressed this gene in Arabidopsis thaliana. Two transgenic lines, designated as OE3 and OE7, were further characterized, both molecularly and functionally. The transgenic plants demonstrated smaller basal rosette leaves, shorter and fewer flowering stems, and fewer seeds compared to wild type plants. Gas chromatography-mass spectrometry analysis of the transgenic plants showed that PmSTS was responsible for the production of β-sesquiphellandrene.

Exogenous proline significantly affects the plant growth and nitrogen assimilation enzymes activities in rice (Oryza sativa) under salt stress

Salinity has been shown to be a major factor contributing to low nitrogen availability in plants. To verify the changes in nitrogen metabolism activity as affected by the exogenous application of proline under salt stress and its relation to salt tolerance, in vitro rice shoot apices were used as a model to study the growth performance and changes in nitrogen assimilation activities in two Malaysian rice cultivars MR 220 and MR 253. Results revealed that salt stress greatly reduced the plant height, shoot nitrate (NO3−) content, shoot glutamine synthetase (GS), and root nitrate reductase (NR) activities in both cultivars. Supplementation of proline significantly increased the plant height, number of roots, root NO3− content, root NR, and root GS activities under salt stress in both cultivars with greater enhancement in MR 253 than MR 220. The results also indicated that MR 253 possessed higher nitrite reductase (NiR) and glutamate synthase (NADH–GOGAT) activities as compared with MR 220 in all tested treatments. It was suggested that the NO3− content, NR, and GS activities played important roles in regulating nitrogen metabolism under salt stress. Taken together, it was concluded that the ability of proline in mitigating salt stress-induced damages was correlated with the changes in nitrogen assimilation activities.

Structure and Principal Components Analyses Reveal an Intervarietal Fusion in Malaysian Mistletoe Fig (Ficus deltoidea Jack) Populations

Genetic structure and biodiversity of the medicinal plant Ficus deltoidea have rarely been scrutinized. To fill these lacunae, five varieties, consisting of 30 F. deltoidea accessions were collected across the country and studied on the basis of molecular and morphological data. Molecular analysis of the accessions was performed using nine Inter Simple Sequence Repeat (ISSR) markers, seven of which were detected as polymorphic markers. ISSR-based clustering generated four clusters supporting the geographical distribution of the accessions to some extent. The Jaccard’s similarity coefficient implied the existence of low diversity (0.50–0.75) in the studied population. STRUCTURE analysis showed a low differentiation among the sampling sites, while a moderate varietal differentiation was unveiled with two main populations of F. deltoidea. Our observations confirmed the occurrence of gene flow among the accessions; however, the highest degree of this genetic interference was related to the three accessions of FDDJ10, FDTT16 and FDKT25. These three accessions may be the genetic intervarietal fusion points of the plant’s population. Principal Components Analysis (PCA) relying on quantitative morphological characteristics resulted in two principal components with Eigenvalue >1 which made up 89.96% of the total variation. The cluster analysis performed by the eight quantitative characteristics led to grouping the accessions into four clusters with a Euclidean distance ranged between 0.06 and 1.10. Similarly, a four-cluster dendrogram was generated using qualitative traits. The qualitative characteristics were found to be more discriminating in the cluster and PCA analyses, while ISSRs were more informative on the evolution and genetic structure of the population.

Molecular cloning and characterization of novel phytocystatin gene from turmeric, Curcuma longa

Phytocystatin, a type of protease inhibitor (PI), plays major roles in plant defense mechanisms and has been reported to show antipathogenic properties and plant stress tolerance. Recombinant plant PIs are gaining popularity as potential candidates in engineering of crop protection and in synthesizing medicine. It is therefore crucial to identify PI from novel sources like Curcuma longa as it is more effective in combating against pathogens due to its novelty. In this study, a novel cDNA fragment encoding phytocystatin was isolated using degenerate PCR primers, designed from consensus regions of phytocystatin from other plant species. A full-length cDNA of the phytocystatin gene, designated CypCl, was acquired using 5′/3′ rapid amplification of cDNA ends method and it has been deposited in NCBI database (accession number KF545954.1). It has a 687 bp long open reading frame (ORF) which encodes 228 amino acids. BLAST result indicated that CypCl is similar to cystatin protease inhibitor from Cucumis sativus with 74% max identity. Sequence analysis showed that CypCl contains most of the motifs found in a cystatin, including a G residue, LARFAV-, QxVxG sequence, PW dipeptide, and SNSL sequence at C-terminal extension. Phylogenetic studies also showed that CypCl is related to phytocystatin from Elaeis guineensis.

Anti-HMG-CoA Reductase, Antioxidant, and Anti-Inflammatory Activities of Amaranthus viridis Leaf Extract as a Potential Treatment for Hypercholesterolemia

Inflammation and oxidative stress are believed to contribute to the pathology of several chronic diseases including hypercholesterolemia (elevated levels of cholesterol in blood) and atherosclerosis. HMG-CoA reductase inhibitors of plant origin are needed as synthetic drugs, such as statins, which are known to cause adverse effects on the liver and muscles. Amaranthus viridis (A. viridis) has been used from ancient times for its supposedly medically beneficial properties. In the current study, different parts of A. viridis (leaf, stem, and seed) were evaluated for potential anti-HMG-CoA reductase, antioxidant, and anti-inflammatory activities. The putative HMG-CoA reductase inhibitory activity of A. viridis extracts at different concentrations was determined spectrophotometrically by NADPH oxidation, using HMG-CoA as substrate. A. viridis leaf extract revealed the highest HMG-CoA reductase inhibitory effect at about 71%, with noncompetitive inhibition in Lineweaver-Burk plot analysis. The leaf extract showed good inhibition of hydroperoxides, 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), and ferric ion radicals in various concentrations. A. viridis leaf extract was proven to be an effective inhibitor of hyaluronidase, lipoxygenase, and xanthine oxidase enzymes. The experimental data suggest that A. viridis leaf extract is a source of potent antioxidant and anti-inflammatory agent and may modulate cholesterol metabolism by inhibition of HMG-CoA reductase.

Towards a better understanding of Artemisia vulgaris : Botany, phytochemistry, pharmacological and biotechnological potential

Artemisia vulgaris is one of the important medicinal plant species of the genus Artemisia, which is usually known for its volatile oils. The genus Artemisia has become the subject of great interest due to its chemical and biological diversity as well as the discovery and isolation of promising anti-malarial drug artemisinin. A. vulgaris has a long history in treatment of human ailments by medicinal plants in various parts of the world. This medicinal plant possesses a broad spectrum of therapeutic properties including: anti-malarial, anti-inflammatory, anti-hypertensive, anti-oxidant, anti-tumoral, immunomodulatory, hepatoprotective, anti-spasmodic and anti-septic. These activities are mainly attributed to the presence of various classes of secondary metabolites, including flavonoids, sesquiterpene lactones, coumarins, acetylenes, phenolic acids, organic acids, mono- and sesquiterpenes. Studies related to A. vulgaris morphology, anatomy and phytochemistry has gained a significant interest for better understanding of production and accumulation of therapeutic compounds in this species. Recently, phytochemical and pharmacological investigations have corroborated the therapeutic potential of bioactive compounds of A. vulgaris. These findings provided further evidence for gaining deeper insight into the identification and isolation of novel compounds, which act as alternative sources of anti-malarial drugs in a cost-effective manner. Considering the rising demand and various medical applications of A. vulgaris, this review highlights the recent reports on the chemistry, biological activities and biotechnological interventions for controlled and continuous production of bioactive compounds from this plant species.

Quantitative assessment of indica rice germination to hydropriming, hormonal priming and polyethylene glycol priming

2 CHILEAN JOURNAL OF AGRICULTURAL RESEARCH 76(1) JANUARY-MARCH 2016 4 OCTOBER DECEMBER 2016 Seed priming is a useful technique which improves seed germination parameters. The present investigation was conducted to evaluate some of the most important germination parameters such as total germination, germination rate, mean germination time, average speed, germination percentage (GP), germination vigor index (GVI), relative frequency, plumule fresh and dry weight, radical fresh and dry weight, plumule and radical length, leaf and root proline content of six indica rice (Oryza sativa L.) varieties, including MR219, MR219-4, MR219-9, MR220, MR159, and MR 211 under hydro-, hormonaland polyethylen glycol (PEG)priming conditions. The highest germination parameters were achieved under the hydro-priming treatment, at 18 h (100%), 6 h (100%), 18 h (90.3%), 12 h (91.6%), 18 h (86.6%), and 18 h (78.3%) for the genotypes MR219, MR219-4, MR2199, MR220, MR159, and MR211, respectively. The best germination feedback of the rice varieties under the hormonal priming were observed in 50 mg L abscisic acid (ABA), 10 mg L gibberellic acid-3 (GA3), 50 mg L indole-3-acetic acid (IAA), 50 mg L GA3, 100 mg L ABA, and 10 mg L GA3 for the genotypes MR219, MR219-4, MR219-9, MR220, MR159 and MR211, respectively. The rice varieties showed different responses to various levels of PEG in which MR219, MR219-4 and MR219-9 responded positively to higher PEG levels, while MR220, MR159 and MR211 showed better feedback under lower PEG concentrations. These outcomes comply with the higher tolerance of MR219, MR219-9 and MR219-4 varieties to drought stress.

Alternative Strategy in Crop Protection: Protease Inhibitors from Turmeric

In an effort to meet the increasing demand for food arising from the growing human population, it is important to ensure food security by maintaining the continual supply of crop products and increase their productions. However, crops plantations are often challenged by the presences of pest insects and pathogens that could inflict diseases or feed on the crop plants and lead to massive losses in the crop productions. While chemical pesticides are commonly employed to control pest insects and pathogens problems, it is often associated with numerous negative side effects and excessive usage would cause lasting detrimental effects to the environments and consumers. Alternatively, crop plants with improved traits were produced through the application of biotechnology techniques to provide phytoprotection against pest insects and pathogens. Genes that encode for natural plant defence products, such as protease inhibitors, are genetically engineered into the crop plants and it is reported to be effectively showing insecticidal and anti-pathogenic properties. For this purpose, it is crucial to constantly discover uncharacterized protease inhibitors from novel sources as candidate for phytoprotection as this helps to overcome the adaptation and resistance buildup by the pest insects and pathogens. Turmeric plant is a well-known herbal plant commonly used as traditional medicine and it acts as a suitable novel source for discovery of protease inhibitors. As turmeric’s secondary metabolites are reported to exhibit a wide range of medicinal properties, it could be contributed by protease inhibitors which possessed high anti-pathogenic and inhibitory properties.