Nepal Journal of Biotechnology
Not a member yet
208 research outputs found
Sort by
Regeneration Technique of Bamboo Species through Nodal Segments: A Review
Micropropagation is an alternative technique to propagate at large scale plants to meet global plant demand. Various researchers have worked on the micropropagation technique to regenerate bamboo species by using nodal segments from years. Contamination, browning, necrosis, and acclimatization with physiological stress are the extreme problems of the micropropagation technique. But, many numbers of papers have been published on micropropagation of the bamboo species through nodal segments as explants. The proliferation of the bamboo shoots is dependent on the season of collection, size of explants, the position of explants, diversity of plants, concentration and combination of plant growth regulators, most adequate culture medium, environmental condition of the equipment, handling, and individual species. Bamboo is a monocarpic fast-growing, tall perennial grass and having the high potential to generate economic and social benefits. It helps to maintain land patterns and control soil erosion. The long life cycle of the bamboo produces a huge amount of seeds but unfortunately, mostly, they are non-viable. So, bamboos are propagated from vegetative by cutting and air layering. However, these methods are only for a small scale and they also tend to destroy large mother plant stocks and difficult to be transported. So, the in vitro propagation technique is useful to obtain large progenies from desired genotypes. Mostly, BAP and TDZ growth hormones are widely used for shoot multiplication and IBA, NAA and IAA are used for root initiation as per developed protocols in tissue culture for large scale production. This review intends to explore an overview of the recent literature reports to summarize the importance of micropropagation by using nodal segments of bamboo species and factors influencing it
Study of the Impact of Organic Manures and Biofertilizers on growth of Phaseolus aureus Roxb.
Weed sare wild plants growing where they are not wanted, and they compete with the cultivated crop for nutrition. Though they are seen as agricultural waste throughout the year, they are rich sources of nutrients. They grow in abundance during the rainy season, but as the season ends these biomasses get wasted. In the present investigation, Tephrosia hamiltonii Drumm belonging to family Fabaceae, and Achyranthes aspera L. belonging to the family Amaranthaceae were used as a nutrient source to develop crop Phaseolus aureus Roxb. Weed manures, Vermicompost and Compost, were prepared by using weeds T.hamiltonii Drumm and A.aspera L. in 1:1 proportion. Chemical analysis of weed and weed manures were done before administering it into the soil. Neem cake was also used as one of the organic manures. In the experiment, a single dose of biofertilizers Azotobacter and Phosphate solubilizing bacteria were mixed with Weed Vermicompost, Weed Compost and Neem cake; and in one of the treatments, only biofertilizers were used indouble dose. Treatments were given to the crop as ATVB, ATCB, NCB, BioD, NPK, and Control in a randomized block design of experimental plot size 1.5X 1.5 m. The use of chemical pesticides or fertilizers was completely avoided except for NPK treatment plots. Single plant analysis of pulse crop P. aureus Roxb. was done. Observations were recorded in the forms of fresh weight and dry weight of root, stem, leaves, leaf (4th number), and legumes. Total fresh yield (kg ha-1), DM (kg ha-1) increase over control, and Nitrogen efficiency ratio were recorded. Results showed that %DM (an increase over control) and DM kg ha-1 recorded highest in ATVB treatment and the highest N efficiency ratio was in BioD. The present investigation emphasized reducing the input cost of the farm products along with protection of the environment and natural resources
Comparative Assessment of Antibiotic Resistance in Lactic Acid Bacteria Isolated from Healthy Human Adult and Infant Feces
Lactic acid bacteria are normal inhabitants of the gastrointestinal tract of humans. Their occurrence in infant and adult feces is abundant. The current study assesses and compares the antibiotic resistance in lactic acid bacteria isolated from healthy human adult and healthy infant fecal samples. A total of 255 lactic acid bacteria isolates (126 from adult feces and 129 from infant feces) were isolated and characterized from 60 fecal samples. Lactobacillus spp., Pediococcus spp. and Enterococcus spp. were included in the study. The study was done using the WHONET software for the analysis of antibiotic susceptibility data of lactic acid bacteria. Most of the Lactobacillus and Pediococcus strains were sensitive to vancomycin. Enterococcus strains showed resistance against vancomycin. Ampicillin, ciprofloxacin and cefuroxime resistance were significantly (p<0.05) higher in Lactobacillus strains isolated from adult fecal samples than those isolated from infant fecal samples. A similar pattern was observed in Enterococcus strains with erythromycin, gentamycin and tobramycin resistance. Pediococcal isolates from adult feces showed significantly higher resistance against tobramycin, ciprofloxacin, gentamycin, cefotaxime and cefuroxime in comparison with infant fecal isolates. Antibiotic resistance was exhibited by lactic acid bacteria against most commonly used antibiotics and it was higher in strains isolated from adult fecal samples than in the strains isolated from infant fecal samples. The increasing trend in antibiotic resistance from infant to adult might be due to food habits and antibiotic intakes. Thus, the widespread antibiotic resistance in different lactic acid bacteriamay pose a food safety concern as well
Regeneration Technique of Bamboo Species through Nodal Segments: A Review
Micropropagation is an alternative technique to propagate at large scale plants to meet global plant demand. Various researchers have worked on the micropropagation technique to regenerate bamboo species by using nodal segments from years. Contamination, browning, necrosis, and acclimatization with physiological stress are the extreme problems of the micropropagation technique. But, many numbers of papers have been published on micropropagation of the bamboo species through nodal segments as explants. The proliferation of the bamboo shoots is dependent on the season of collection, size of explants, the position of explants, diversity of plants, concentration and combination of plant growth regulators, most adequate culture medium, environmental condition of the equipment, handling, and individual species. Bamboo is a monocarpic fast-growing, tall perennial grass and having the high potential to generate economic and social benefits. It helps to maintain land patterns and control soil erosion. The long life cycle of the bamboo produces a huge amount of seeds but unfortunately, mostly, they are non-viable. So, bamboos are propagated from vegetative by cutting and air layering. However, these methods are only for a small scale and they also tend to destroy large mother plant stocks and difficult to be transported. So, the in vitro propagation technique is useful to obtain large progenies from desired genotypes. Mostly, BAP and TDZ growth hormones are widely used for shoot multiplication and IBA, NAA and IAA are used for root initiation as per developed protocols in tissue culture for large scale production. This review intends to explore an overview of the recent literature reports to summarize the importance of micropropagation by using nodal segments of bamboo species and factors influencing it
Standardization of Ayurvedic Drug- Nyctanthes arbor-tristis, Hippophae salicifolia, Ocimum tenuiflorum and Reinwardtia indica and Combined Herb-Herb
The herbal medicines have reached extensive acceptability as therapeutic agents for various clinical diseases due to global demand. Therefore, standardization is the essential and initial step to drug development. It is for the establishment of consistent biological activity, a consistent chemical profile and biomarker identification. It improves the safety and efficacy of herbal medicine to provide the best herbal medicine to society and increase popularity rather than non-standardized extracts. In addition, it is essential to practice or maintain a quality assurance program for the production and manufacturing of herbal medicine that includes the basis of organoleptic characters and photomicrographs, physicochemical, proximate analysis phytochemical evaluation and quality control analysis and order to assess the quality of drugs, based on the concentration of their active principles. WHO has provided specific guidelines for the assessment of the safety, efficacy and quality of herbal drugs as a prerequisite for global harmonization and of utmost importance. In the present study, the herbal extracts were cleaned, dried in the shade and powdered by passing through the sieve as per the method described in the standard protocol. An overview covering various techniques employed in the extraction and characterization of Nyctanthes arbortristis, Hippophae salicifolia, Ocimum tenuiflorum and Reinwardtia indica, standardization is reported in this study. The obtained data would be very significant for future clinical aspects, as the bioactive molecules present in the extracts may exhibit synergistic effect with other bioactive compound and show a better therapeutic value. Thus, this study provides standardized and therapeutically potential data of active polyherbal formulations for the different ailments
Phytochemical Evaluation, Antioxidant and Antimicrobial Activities of Various Extracts from Leaves and Stems of Bryophyllum pinnatum
Antioxidant and antimicrobial activities of different extracts (methanol and ethyl acetate) of leaf and stem of Bryophyllum pinnatum were studied. The screening for the secondary metabolites was carried out using the standard methods. The antioxidant capacities of the different extracts were assessed using DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and Ferric reducing antioxidant power (FRAP) while the antimicrobial activity of the extracts obtained were screened against Gram-positive, Gram-negative bacteria and fungi (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa Salmonella spp., Vibrio cholerae, Candida albicans and Aspergillus niger) using Agar well diffusion method. Both extracts obtained from leaf and stem of Bryophyllum pinnatum contained most of the phytochemical compounds tested for. However, anthocyanins and anthraquinone were not detected in leaf extracts while coumarin was absent in stem extracts. Quantification of bioactive compounds showed that both extracts contained the highest concentration of polyphenols (34.49 ±0.47 mg GAE/g and 32.32 ±1.2 mg GAE/g for methanol leaf and stem extracts respectively) while the least concentration was recorded for alkaloids (0.03±0.02 mg/g for methanol stem extract). Results revealed that the extracts showed dose-dependent scavenging of DPPH as well as the ability of the extracts to reduce FeCl3 solution, with methanol extracts exhibiting the highest scavenging and reducing capacity. However the leaves of Bryophyllum pinnatum had greater antioxidant activity than the stem by DPPH and ferric reducing assays, with IC50 values ranging from 3.147µg/ml to 3.80µg/ml for DPPH and 331.9 - 451 µg/ml for FRAP assays. The antimicrobial activity of various solvent extracts of leaf and stem reveal that microorganisms exhibited different sensitivities towards these extracts in a dose-dependent manner. Methanol leaf extract showed no activity against Escherichia coli while Pseudomonas aeruginosa was insensitive to ethyl acetate leaf extract. For stem extracts, Aspergillus niger, Vibrio cholerae and Pseudomonas aeruginosa were resistant to methanol extract while Aspergillus niger, Salmonella spp. and Pseudomonas aeruginosa was resistant towards ethyl acetate stem extract. The results obtained in this study showed that Bryophyllum pinnatum is a reservoir of bioactive compounds and both extracts exhibited significant antimicrobial and antioxidant activity
Phytochemicals Levels and Antioxidant Capacities of Figs Flowers Fruits
Since antiquity, phenolic compounds produced by plants were known as free radical scavengers and as powerful antioxidants. Huge interest has been made by researchers to the traditional uses of medicinal plants against illnesses related to oxidative stress. This study measures the correlation that can be existed between the antioxidant capacity and phytochemical s levels of four varieties of Ficus carica fruits, figs flowers or "Bakor" as called locally in Algeria. Therefore, extracts were assessed for determining their antioxidative potentials using both test of total antioxidant capacity and DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging test followed by quantitative phytochemical analysis to estimate the total flavonoid level (TFL), the total phenolic level (TPL), the total anthocyanin level (TAL) and the condensed tannins level of plants methanolic extracts. A positive correlation was observed between phenolics content and the antioxidant capacity of figs flowers methanol extracts. The methanolic extract of Bechar (MeOH Var.2) chelated 87,9± 1,23 % of the DPPH free radical with IC50 value equal to 0,185 mg/g DW. A high antioxidant ability of almost all extracts is, probably, related to the appreciable rates of flavonoids, phenolics and tannins showed by those fig extracts. The highest value of phenolics level was detected among the variety 1 methanolic extract of Bechar (MeOH Var.1) of 10,4 mg GAE/g DW
Comparative Study of Bioactive Compounds in Different Varieties of Pears in Nepal
This study was conducted to evaluate the physicochemical parameters, perform qualitative tests (for sugars and phytochemicals), and quantitative tests (phenolics, antioxidants, anthocyanins, tannins, vitamin C) of six different varieties of pears i.e. Bartlette, Chinese pears, Chojuro, Kosui, Pharping local, and Yakumo. The juices extracted from respective pears were used for the analysis. The phenols were determined by the Folin-Ciocalteu method, antioxidants by the DPPH scavenging activity, and anthocyanins by a SO2 bleaching technique. The Pharping local pears were found to have the highest anthocyanins (85.95±0.1 mg/l), total phenolic content (600±0.01 mg GAE/l), antioxidants (IC50 value 250±0.00 mg of phenol/l) and vitamin C content (12.2±0.01 mg/100 ml) and tannins were observed to be highest in Yakumo pears (0.93±0.01 g/l). Likewise, the highest clarity i.e. 1.960±0.00 was observed in Bartlette pears and the highest acidity (2.01±0.01%) in Chojuro pears. Various sugar/carbohydrate tests like Molisch’s test, Benedict’s test, Barfoed test, Bial’s test, Seliwanoff test, Fehling’s test and Iodine test were performed for the pear varieties. All the pears gave positive results for all the sugar tests except Iodine test. The positive results for sugar/carbohydrate signifies the presence of various sugars that help for the better taste, texture, and aroma of pear. The pear varieties showed the presence of phytochemicals like flavonoids, terpenoids, catechins, cyclic glycosides, and proteins. The phytochemicals are responsible for fruit preservation and act as anti-carcinogenic components. Among the varieties of pears, Pharping local pears were observed to be most nutritional because of high antioxidants, phenols, anthocyanins, and vitamin C
Genetic Diversity in Finger Millet Landraces revealed by RAPD and SSR Markers
Genetic diversity assessment is the preliminary work for development of variety and conservation of diversity. Finger millet is a very important crop in Nepal however, its genetic potential has not been fully utilized. Genetic diversity was assessed in forty landraces of finger millet using 9 RAPD and 5 SSR markers. These landraces were collected from Kaski and Dhading districts. None of single primers of these RAPD and SSR could separate all 40 landraces. The average number of bands were 6.33 and 7.8 per RAPD and SSR primers respectively. Mean polymorphism information content was of 0.314 for RAPD and 0.37 for SSR. Primer OPA-4 produced the highest number of bands and the lowest numbers of bands were produced by OPA-16. Among the SSR primers, SSR-06 produced the highest number of polymorphic bands and UGEP-53 produced the lowest bands. RAPD based dendrogram has generated four clusters and SSR based dendrogram has generated two clusters. In both dendrogram and principal component analyses, Purbeli landrace was found unique locating separately in the cluster and scatter plot. Nei\u27s genetic distance produced by RAPD and SSR primers was similar that is 0.327 by RAPD and 0.296 by SSR markers. Genetic distance produced by SSR markers was higher than distance produced by RAPD marker. These landraces were from two districts and therefore have shown intermediate diversity. These molecular marker-based findings should would be more useful if we could link with agromorphological traits. Inclusion of large number of landraces collected from different areas are required to get higher level diversity in addition to associate genetic diversity with geographical sites. Groupings of these landraces could be useful for selecting landraces in breeding program as well as planning conservation program
Phytochemicals Levels and Antioxidant Capacities of Figs Flowers Fruits
Since antiquity, phenolic compounds produced by plants were known as free radical scavengers and as powerful antioxidants. Huge interest has been made by researchers to the traditional uses of medicinal plants against illnesses related to oxidative stress. This study measures the correlation that can be existed between the antioxidant capacity and phytochemical s levels of four varieties of Ficus carica fruits, figs flowers or "Bakor" as called locally in Algeria. Therefore, extracts were assessed for determining their antioxidative potentials using both test of total antioxidant capacity and DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging test followed by quantitative phytochemical analysis to estimate the total flavonoid level (TFL), the total phenolic level (TPL), the total anthocyanin level (TAL) and the condensed tannins level of plants methanolic extracts. A positive correlation was observed between phenolics content and the antioxidant capacity of figs flowers methanol extracts. The methanolic extract of Bechar (MeOH Var.2) chelated 87,9± 1,23 % of the DPPH free radical with IC50 value equal to 0,185 mg/g DW. A high antioxidant ability of almost all extracts is, probably, related to the appreciable rates of flavonoids, phenolics and tannins showed by those fig extracts. The highest value of phenolics level was detected among the variety 1 methanolic extract of Bechar (MeOH Var.1) of 10,4 mg GAE/g DW