Health benefits of Stevia rebaudiana Bertoni as zero calorie natural sweetener: a review

Stevia rebaudiana Bertoni is a perennial herbal species with a number of therapeutic properties. The leaves of S. rebaudiana are the most important part of the plant as they contain high level of sweetener compounds known as steviol glycosides; which are known to possess antioxidant, antimicrobial, and antifungal activities. Among the steviol glycosides, stevioside and rebaudioside A are the most abundant sweetening compounds of interest, documented to be 30 - 250 folds sweeter than sucrose or refined sugar. The therapeutic properties of the species make it more interesting as they play important roles as anti hyperglycaemic agent to lower glucose levels in the blood, thus commonly used in the treatment of diabetes mellitus and obesity. Known to have sweet tasting leaves, its extract which contains antioxidant compounds have been used to treat cancer, reduce inflammatory, and hypertension. S. rebaudiana has drawn the attention of health-conscious fitness lovers all over the world as non-caloric sweetener, and has been widely cultivated for being the most suitable sweetening substitution

In vitro responses of plant growth factors on growth, yield, phenolics content and antioxidant activities of Clinacanthus nutans (Sabah snake grass)

Clinacanthus nutans, commonly known as Sabah snake grass, is one of the more important medicinal plants in Malaysia’s herbal industry. C. nutans has gained the attention of medical practitioners due to its wide range of bioactive compounds responsible for various biological activities, such as anti-cancer, anti-venom and anti-viral activities. Due to its high pharmacological properties, the species has been overexploited to meet the demands of the pharmaceutical industry. The present study was conducted to establish a suitable in vitro culture procedure for the mass propagation of C. nutans. Murashige and Skoog (MS) basal medium, supplemented with different types of cytokinins, auxins, basal medium strength and sucrose concentrations, were tested. Based on the results, a full-strength MS basal medium supplemented with 12 µM 6-benzylaminopurine (BAP) and 30 g/L sucrose was recorded as the best outcome for all the parameters measured including the regeneration percentage, number of shoots, length of shoots, number of leaves and fresh weight of leaves. In the analysis of the phenolics content and antioxidant activities, tissue-cultured leaf extracts assayed at 100 °C exhibited the highest phenolic content and antioxidant activities. The propagation of C. nutans via a plant tissue culture technique was recorded to be able to produce high phenolic contents as well as exhibit high antioxidant activities

Estimation of total phenolic acids, flavonoid compounds and antioxidant activity of Ficus deltoideavarieties and their HPLC profiles with different solvents

The aim of this study was to evaluate the effect of methanol and ethanol extraction on antioxidant activities, total polyphenol, phenolic acid and flavonoid content of different Ficus deltoideavarieties. Our findings revealed that fresh leaves of F. deltoideavar. kunstleri; FDK1 had the highest total polyphenol, phenolic acid, flavonoid and antioxidant activities compared to that of other varieties. Ethanol extraction of FDK1 showed the highest activity in total antioxidant (DPPH) (4.48 mg TE/g FW), polyphenol (1.13 mg GAE/g FW) and flavonoid content (6.81 mg RE/g FW) while methanol extraction showed the highest activity in total antioxidant (FRAP) (2.43 mg TE/g FW) and phenolic acid content (4.54 mg GAE/g FW). HPLC quantification in dried leaves of FDK1 found out rutin exhibited higher than naringin. The highest rutin and naringin was found in FDK1 and FDT2 (12.83 and 3.04 μg/g DW). These results demonstrate that extraction solvent and F. deltoideavariety influence the activity of total antioxidant, polyphenol, phenolic acid and flavonoid content

In vitro mutagenesis using bio-beam irradiation on in vitro culture of Cavendish banana cultivar (Musa acuminata Colla) explants

Banana, Musa acuminata cv. Cavendish, was commonly propagated by use of suckers from selected field grown clumps. An in vitro technique has in recent years provided with rapid and efficient system propagation. However, high demand for planting material has caused significant shortages and subsequently attempts at improving the efficiency of in vitro propagation technique have been initiated. The current study investigated the effect of gamma irradiation using bio-beam on in vitro propagation of banana cv. Cavendish. The main objective was to assess the effect of mutation induction using gamma source on growth and development of plantlets while in culture. Tissue cultured banana plantlets were used as source of explant materials. The plantlet was trimmed of leaves and halved before culturing on Murashige and Skoog (MS) media. Then, the explants radiated with gamma source using Ion-Beam with selected dose [0 (control), 30 Gy, 60 Gy, 90 Gy, 120 Gy and 150 Gy] and transferred to fresh MS media with 5 mg/l of BAP. The analysis showed dosage of 30 Gy and 60 Gy produced significant survival rate and favourable effect on growth especially on plant height, shoot number, leaf production and root production. Thus, this study contributed to develop in vitro mutagenesis of M. acuminata cv. Cavendish through gamma rays coupled with in vitro system for future breeding of new varieties of banana

Factors affecting cell biomass and flavonoid production of Ficus deltoidea var. kunstleri in Cell Suspension Culture System

A study was conducted to establish in vitro culture conditions for maximum production of biomass and flavonoid content for Ficus deltoidea var. kunstleri, locally named as Mas Cotek, known to have a wide variety of potential beneficial attributes for human health. Size of initial inoculum, cell aggregate and initial pH value have been suggested to influent content of biomass and flavonoid for cell suspension culture in several plant species. In the present study, leaf explants were cultured by cell suspension culture procedures in MSB5 basal medium supplemented with predetermined supplements of 30 g/L sucrose, 2.75 g/L gelrite, 2 mg/L picloram and 1 mg/L kinetin with continuous agitation of 120 rpm in a standard laboratory environment. Establishment of cell suspension culture was accomplished by culturing resulting callus in different initial fresh weight of cells (0.10, 0.25, 0.50, 1.0, and 2.0 g/25 mL of media) using similar basal medium. The results showed that the highest production of biomass (0.65 g/25 mL of media) was recorded from an initial inoculum size of 2.0 g/25 mL media, whereas the highest flavonoid (3.3 mg RE/g DW) was found in 0.5 g/25 mL of media. Cell suspension fractions classified according to their sizes (500–750 µm, 250–500 µm, and <250 µm). Large cell aggregate size (500–750 µm) cultured at pH 5.75 produced the highest cell biomass (0.28 g/25 mL media) and flavonoid content (3.3 mg RE/g DW). The study had established the optimum conditions for the production of total antioxidant and flavonoid content using DPPH and FRAP assays in cell suspension culture of F. deltoidea var. kunstleri

In vitro growth responses of Gynura procumbens to different medium strengths and BAP concentrations

Gynura procumbens is an important medicinal plant belongs to Asteraceae family. G. procumbens is traditionally used in treatment of various ailments such as diabetes, cancer and hypertension. Due to its beneficial values, the demand for raw material of G. procumbens is keep increasing. However, the conventional propagation of G. procumbens is slow and not uniform. Hence, in vitro technique was proposed to produce massive amount of G. procumbens plantlets. The nodal segments of G. procumbens were used as explants and inoculated onto the MS media. The study was carried out by using Completely Randomized Design (CRD) with two factorials; media strength (quarter, half and full strength of MS) and BAP concentration (0, 1.25, 2.50, 3.75 and 5.00 mg/L). Based on the results, full strength MS media with 1.25 mg/L BAP produced the highest number of shoot. However, the highest yield was obtained from the full strength MS media with 3.75 mg/L BAP. The highest number of leaves, fresh and dry weight also was obtained from nodal segments cultured in full strength MS media with 3.75 mg/L BAP. For the root induction, the most suitable media was found in full strength MS media without addition of plant growth regulators. From this finding, mass production of raw materials of G. procumbens can be produced in a short time, hence, the market demand for raw materials of G. procumbens can be fulfilled for industrial purposes

Diagnostic approach and genetic diversity of jackfruit bronzing bacterium in Malaysia

A serious problem faced in the jack fruit industry in Malaysia caused by bronzing disease by pathogen Pantoea stewartii subspe. stewartii (P. stewartii subsp. stewartii ) as it reduces the quality of the fresh jack fruit, hence, affects the consumer preference towards the fruits. It is important to keep the fruit healthy as it provides revenue to the local and export markets in Malaysia. This review aimes to present an overview and diagnostic approach of jackfruit bronzing disease in Malaysia. Detection and identification methods following past and recent study of the causal pathogen via phenotypic identification, molecular identification, pathogenicity test, genetic relationship and genetic diversity. Successful detection and identification were obtained with appropriate phenotypic tests performed and molecular identification using CPSL1/CPSR2c primers and ES16/ESIG2c primers. Pantoea stewartii subsp. stewartii strains were also pathogenic to healthy detached and attached jack fruit and the high liability of the phylogenetic and clustering analyses in the causal pathogen via multilocus sequencing analysis (MLSA) of the partial nucleotide sequences of the genes gyrB, rpoB, atpD and infB, using a bootstrap analysis with 1000 replicates on the individual and concatenated peptide sequence trees. The presented review provides an overview on bronzing disease of jackfruit in Malaysia, the appropriate detection, identification, pathogenicity of its causal pathogen and the application of multilocus sequence analysis (MLSA) as the best tool to study the pathogen diversity and evolution. Up to now, little information and studies have been done on bronzing disease of jackfruit and its causal agent, P. stewartii subsp. stewartii in Malaysia

Draft genome sequencing data of a pathogenic Pantoea stewartii subspecies stewartii strain SQT1 causing bronzing disease of jackfruit in Malaysia

A Gram-negative bacterium, Pantoea stewartii subspecies stewartii (P. stewartii subsp. stewartii) has been recognized as the causative agent for jackfruit bronzing disease in Malaysia. Here, we report the whole genome sequencing dataset of P. stewartii subsp. stewartii strain SQT1 isolated from local infected jackfruit. The paired-end libraries with an insert size of 350 bp was subjected to the Illumina Hiseq 4000, generating a genome size of 4,783,993 bp with a G+C content of 53.7%. A total protein of 4,671 was identified including virulence factors, resistance factors and secretion systems. Pantoea stewartii subsp. stewartii strain DC283 (NCBI accession no. CP017581.1) was used as a reference genome, where the query hit 72% coverage and average sequencing depth of 68. In total, 28,717 nucleotide polymorphisms, 520 small insertion/deletions and 142 structure variants were identified. The complete genome was deposited at the European Nucleotide Archive under the sample accession number ERP119356 and study accession number PRJEB36196