Sanjay Guleria

Natural Products: Bioactivity, Biochemistry, and Biological Effects in Cancer and Disease Therapy

The drug discovery for chemoprevention and chemotherapy remains a challenge. Natural products-derived extracts and compounds are frequently reported to discover therapeutic agents for disease and cancer. The overall scenario of this special issue of The Scientific World Journal presents the recent advances in biological function of selected natural products for cancer and disease therapy in terms of crude extracts and components. Some studies describe the bioinformatics tool to help to investigate the field of natural products. The papers by S. Guleria et al. and C.-C. Lee et al. provide the essential oil and/or extracts of herb Zanthoxylum alatum and Zingiber officinale for its antioxidant and antimicrobial properties, respectively. O. O. Igbinosa et al. and C.-C. Lee et al. provide the animal experiments using extractsfrom Jatropha curcas (Linn) leaf and from supercritical carbon dioxide extracted ginger, respectively. Three studies (F. M. Al-Jasass and M. S. Al-Jasser, X.-W. Chen et al., and C.-Y. Lo et al.) focus on biological functions of the compounds from Saudi Arabia herbs, Chinese herb Huang Lian (Rhizoma coptidis), and from Alpinia galangal, respectively. Further, C.-Y. Yen et al. provide the toxicological study for cardiotoxin III in growth inhibition of oral cancer. C.-Y. Lin et al. provide a review article for the chemoprevention of cytochrome P450 in oral potentially malignant disorders (OPMDs) patients in terms of betel quid metabolism. S.-S. Liang et al. introduce the novel technique for online monitoring oxidative products and metabolites of nicotine based on tandem mass spectrometry. Some papers introduce the bioinformatics methods or resources to study or review the natural products-related studies. L. Wang et al. introduce the gene ontology (GO) network for the systems-theoretical analysis of human hepatocellular carcinoma. Y.-C. Lin et al. provide the database (TIPdb) for anticancer, antiplatelet, and antituberculosis phytochemicals from indigenous plants in Taiwan. Three papers (W.-H. Huang et al. and J.-Y. Tang et al.) provide the drug discovery for cancer and disease therapy in terms of RNA editing, alternative splicing, and long noncoding RNAs as well as the summary for their bioinformatics resources. Hsueh-Wei Chang Li-Yeh Chuang Sanjay Guleria Sammia Yasmin

CRISPathBrick: Modular Combinatorial Assembly of Type II-A CRISPR Arrays for dCas9-Mediated Multiplex Transcriptional Repression in E. coli.

Programmable control over an addressable global regulator would enable simultaneous repression of multiple genes and would have tremendous impact on the field of synthetic biology. It has recently been established that CRISPR/Cas systems can be engineered to repress gene transcription at nearly any desired location in a sequence-specific manner, but there remain only a handful of applications described to date. In this work, we report development of a vector possessing a CRISPathBrick feature, enabling rapid modular assembly of natural type II-A CRISPR arrays capable of simultaneously repressing multiple target genes in Escherichia coli. Iterative incorporation of spacers into this CRISPathBrick feature facilitates the combinatorial construction of arrays, from a small number of DNA parts, which can be utilized to generate a suite of complex phenotypes corresponding to an encoded genetic program. We show that CRISPathBrick can be used to tune expression of plasmid-based genes and repress chromosomal targets in probiotic, virulent, and commonly engineered E. coli strains. Furthermore, we describe development of pCRISPReporter, a fluorescent reporter plasmid utilized to quantify dCas9-mediated repression from endogenous promoters. Finally, we demonstrate that dCas9-mediated repression can be harnessed to assess the effect of downregulating both novel and computationally predicted metabolic engineering targets, improving the yield of a heterologous phytochemical through repression of endogenous genes. These tools provide a platform for rapid evaluation of multiplex metabolic engineering interventions.

Microbial production of value-added nutraceuticals.

Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches.

Chemical Composition and Fungitoxic Activity of Essential Oil of Thuja orientalis L. Grown in the North-Western Himalaya

The essential oil from fresh leaves of Thuja orientalis L. grown in the north-western Himalaya was isolated by means of hydrodistillation and analyzed by GC and GC/MS. Twentytwo compounds representing 94.0% of the total oil were identified. The leaf oil contained α- pinene (29.2%), Δ-3-carene (20.1%), α-cedrol (9.8%), caryophyllene (7.5%), α-humulene (5.6%), limonene (5.4%), α-terpinolene (3.8%) and α-terpinyl acetate (3.5%) as major constituents. The essential oil showed antifungal activity against Alternaria alternata in a direct bioautography assay. Two main bioactive compounds named as b1 (Rf = 0.54) and b2 (Rf = 0.80) were observed and tested for antifungal activity; they produced an inhibition zone of 5 and 10 mm in diameter, respectively. The components b1 and b2 were further purified by preparative thin layer chromatography and their antifungal efficacy was re-tested. The minimum inhibitory amount (MIA) of b1 and b2 against A. alternata was determined as 30.5 and 4.5 μg, respectively, using a bioautography assay. The bioactive constituent corresponding to b1 was determined as α-cedrol by using GC/MS analysis. The potential of essential oils as a source of natural biocides is discussed

Antioxidant and Antimicrobial Properties of the Essential Oil and Extracts of Zanthoxylum alatum Grown in North-Western Himalaya

The essential oil obtained from the fresh leaves of Zanthoxylum alatum was analysed by gas chromatography/mass spectrometry (GC/MS). Fourteen components were identified, and linalool (30.58%), 2-decanone (20.85%), β-fenchol (9.43%), 2-tridecanone (8.86%), β-phellandrene (5.99%), Sabinene (4.82%), and α-pinene (4.11%) were the main components. The EO and methanolic extract of Z. alatum exhibited potent antifungal activity against Alternaria alternata, Alternaria brassicae, and Curvularia lunata. The EO also showed significant antibacterial activity against Bacillus subtilis, Micrococcus luteus, Staphylococcus aureus, and Escherichia coli. Further, antimicrobial constituents of the EO were isolated by bioautography and preparative thin layer chromatography (PTLC) and identified as β-fenchol and linalool using GC/MS analysis. In addition to this, the free radical scavenging activity and antioxidant potential of EO and methanolic extract/fractions of Z. alatum were also investigated using in vitro assays including scavenging ability against DPPH•, reducing power and chelating ability on Fe2+ ions. Our results demonstrate that Z. alatum could be used as a resource of antioxidant and antimicrobial compounds which may find applications in food and pesticide industries.

Antioxidant Activity and Protective Effect Against Plasmid DNA Strand Scission of Leaf, Bark, and Heartwood Extracts from Acacia catechu

UNLABELLED The antioxidant activity of methanol extract/fractions of leaf, bark, and heartwood of Acacia catechu was evaluated by various antioxidant assays, including free radical, superoxide and hydroxyl radical, reducing power, metal ion chelation, as well as hydroxyl radical induced DNA strand scission. The leaf, bark, and heartwood powder was extracted in methanol and the lyophilized methanol extract was fractionated with different solvents in the order of increasing polarity. The results indicate that ethyl acetate fraction of heartwood has the highest antioxidant capacities, presenting lower EC(50) values particularly in free radical scavenging activity, including DPPH radicals (4.76 ± 0.14 μg/mL), superoxide anions (26.21 ± 0.79 μg/mL), and hydroxyl radicals (33.69 ± 1.42 μg/mL), in direct assay systems. Reducing power was also highest in ethyl acetate fraction of heartwood (EC(50) of 79.05 ± 1.02 μg/mL). As for the chelating power on ferrous ions, leaf extract was more effective than bark and heartwood extracts. Furthermore, the ethyl acetate and acetone fractions of heartwood significantly protected pBR322 supercoiled plasmid DNA against strand scission induced by hydroxyl radicals in a Fentons reaction mixture. PRACTICAL APPLICATION The present investigation suggests that the three organs of A. catechu differ significantly in their antioxidant potential as seen in the DPPH radical scavenging assay, reducing power assay, metal ion chelating assay, superoxide radical scavenging assay and hydroxyl radical scavenging assay. Further, our results showed that crude methanol extract and ethyl acetate fraction of heartwood of A. catechu might have a good potential as a source for natural health products due to its antioxidant and DNA protective activities.

Antifungal activity of Agave americana leaf extract against Alternaria brassicae, causal agent of Alternaria blight of Indian mustard (Brassica juncea).

Abstract Leaf extract of Agave americana was evaluated for antifungal activity against Alternaria brassicae, the causal agent of Alternaria blight of Indian mustard [Brassica juncea (L.) Czern. & Coss]. Methanolic leaf extract (crude extract) of A. americana showed antifungal activity against A. brassicae. The green mass obtained by vacuum drying of the crude extract was used for further sequential fractionation using ethyl acetate, n-butanol and methanol. Among the three fractions, the methanolic fraction showed the strongest antifungal activity by its inhibition of conidial germination of A. brassicae. The methanolic fraction of A. americana leaves was fractionated further using open column liquid chromatography into six sub-fractions (I – VI). Among the six sub-fractions tested, sub-fraction II showed a strong inhibitory effect on conidial germination of A. brassicae and thereby inhibited lesion development of Alternaria blight of Indian mustard at a concentration of 40 µg/ml or higher. Qualitative separation of molecules present in sub-fraction II by thin layer chromatography followed by diagnosis with Libermann – Burchard reagent indicated that sub-fraction II contained a mixture of saponins. The potential of using A. americana for the management of fungal pathogens of crop plants is discussed.

Toxicity of Solanum xanthocarpum fruit extract against Alternaria brassicae, causal agent of Alternaria blight of Indian mustard (Brassica juncea).

Fruit extract of Solanum xanthocarpum was evaluated for its toxicity against Alternaria brassicae, the causal agent of Alternaria blight of Indian mustard [Brassica juncea (L.) Czern. & Coss]. The mass obtained after vacuum drying of the crude methanolic extract was utilised for further sequential fractionation using n-hexane, ethyl acetate, n-butanol and methanol. Among the crude and different fractions tested, methanolic fraction was most effective with a minimum inhibitory concentration (MIC) of 62.5 μg/ml. The methanolic fraction was further fractionated using open column liquid chromatography into five subfractions (I–V) to identify the antifungal bioactive compounds. Among the five subfractions (SFs) tested SF IV was most effective at inhibiting A. brassicae conidial germination and thereby inhibited lesion development of Alternaria blight at a concentration of 15.625 μg/ml or higher. Furthermore, bioautography of SF IV with Alternaria alternata and diagnosis with Dragendorff reagent indicated that SF IV contains a mixture of bioactive alkaloids, namely a1 (Rf = 0.12) and a2 (Rf = 0.22). The potential of using S. xanthocarpum as a resource for the development of biofungicides is discussed.

Toxicology and Disease/Cancer Therapy in Reactive Oxygen Species-Mediated Drugs and Treatments

Reactive oxygen species (ROS) induce or protect cellular oxidative damage. ROS are also known to play an important role in apoptosis, autophagy, endoplasmic reticulum stress, mitochondrial dysfunction, cell migration, and invasion. This special issue presents the recent advances in basic research and association studies of some natural products and chemical drugs for cancer and disease treatments. The papers by M.-G. Lee et al. and H.-W. Huang et al. reported the antioxidant/tyrosinase suppression/wound repair properties and antiproliferative effect on oral cancer of Cinnamomum osmophloeum Kanehiraand Cryptocarya concinna Hance root extracts, respectively. Similarly, S.-C. Chien et al. reported the protective effect of Chinese herbal medicine “Jia-wei-xiao-yao-san” against chemical-induced hepatic fibrosis in rats. Y. Fong et al. reported the antiproliferative and antiapoptotic effects on lung cancer cell lines of sirtinol, a sirtuin inhibitor. W.-C. Lee et al. reported that indoxyl sulfate (IS) induced oxidative stress and endothelial dysfunction in chronic kidney disease patients can be due to mitochondrial dysfunction and impaired biogenesis which can be reverted by treatment with antioxidants. The papers by B. Huang et al. and P.-H. Chen et al. provided the findings on the upstream role of H2S and arsenic in modulating protein S-nitrosylation in endothelial cells and keratinocytes, respectively. W.-T. Chang et al. reported that epirubicin/progesterone combination is effective in increasing apoptosis and inversely decreasing autophagy on HA22T/VGH cells and can potentially be used to treat hepatocellular carcinoma. The papers by S.-J. Wu et al. and P.-H. Chen et al. provided the cancer association studies of betel quid-consuming patients in terms of oxidative stress response genes such as polymorphisms for the human retinoic acid (RA) 4-hydroxylase (CYP26), the monoamine oxidase, and the cytochrome P450, family 26, subfamily B, polypeptide 1 (CYP26B1) genes. Finally, the paper by Y.-R. Lin et al. introduced the proteomics technique for evaluating cytotoxicity of unmodified nano-Fe3O4 based on tandem mass spectrometry (LC-MS/MS) and T.-C. Cheng et al. provided the in silico virtual screening to discover specific inhibitors for intestinal E. coli  β-glucuronidase. Hsueh-Wei  Chang Shao-Yu  Chen Li-Yeh  Chuang Sanjay  Guleria