Nepal Journal of Biotechnology
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Phytochemical Analysis and α-Amylase Inhibitory Activity of Young and Mature Leaves of Cinnamomum tamala
Full text linkThe bioactive chemical components of the plant\u27s origin have been used as primary remedies for a wide array of human diseases including diabetes. The present research deal to evaluate and compare anti-diabetic potential of ethanolic and methanolic, young and mature leaves of medicinally valuable Cinnamomum tamala. Total phenolic and flavonoid contents of young and mature leaves were determined. In vitro α-amylase inhibition was carried out using 2-chloro-4-nitrophenyl-α-D-maltotrioside (CNPG3) as substrate. Phytochemical screening revealed the presence of polyphenols, flavonoids, terpenoids, quinones, carbohydrates, glycosides, diterpenes, tannins, and reducing sugars. The highest total phenolic content and flavonoid content were observed in methanolic extract of mature leaves (13.725 ± 0.54 mg GAE/g) and young leaves (12.591 ± 0.71 mg QE/g) respectively. Methanolic young leaves extract showed α-amylase inhibition with IC50 value 224.6 ± 2.76 μg/mL as compared to acarbose with IC50 value 5.93 ± 0.14 μg/mL. The result suggests that young leaves of C. tamala had anti-diabetic activity so further work should be carried out
Advances in Agricultural Biotechnology
Full text linkAgricultural biotechnology is becoming the major sector in crop improvement through the use of scientific techniques for the modification of genes conferring resistance to biotic, abiotic stress and improving the quality of crops. With the evolvement from Mendelian genetics to molecular biotechnology, there have been several developments in the field of crop improvement. Recent biotechnological advances have aimed towards removing the physiological constraints of the crops and increasing crop yield potential. With the use of different tools of agricultural biotechnologies like genetic engineering, tissue culture, embryo rescue, somatic hybridization, molecular marker-assisted selection, genome doubling, and omics technologies, various transgenic crops have been developed over the decades and have been approved for commercialization. This development and adoption of transgenic technology have been shown to increase crop yields, reduce CO2 emission, reduce pesticide and insecticide use and decrease the costs of crop production. Even though the biotechnological approach and transgenic organisms have immense potential to contribute to the world’s food security, several concerns of genetically modified crops being a threat to the environment and human health have developed. This review will address applications and concerns of biotechnology in crop improvement considering health hazards and ecological risks
Intellectual Property Right on Basmati Rice: Current Scenario and Evidences of Origin, Diversity, Cultivation and Use Values of Basmati Rice in Nepal
Full text linkBasmati rice, also called the king/prince of rice landraces has very special values in Nepalese society as well as in other countries of Indian Subcontinent. With the objectives of collecting, analyzing and documenting Basmati related information in Nepal, we visited different sites; carried out key informant surveys; organized focus group discussions, online interaction and discussion meetings; requested all relevant offices/ persons/ stakeholders through phone, website, and letter to share information; organized high level official meeting, and Basmati rice expert meeting; documented video documentary and did online as well as library search. Because of its high market value at global level, many countries and organizations have been attempting to get intellectual property rights (mainly patent and geographical indication tag) on Basmati rice. India applied for GI tag to Basmati rice in the European Union (EU) in July 2018, and Nepal submitted opposition letter along with proofs and evidences of origin, diversity, cultivation and use values of Basmati rice on 9 December 2020. A total 133 Basmati type rice landraces are grown in 60 districts of Nepal. Basmati rice is traditionally grown, sold, and consumed in geographically localized areas of Nepal since ancient time. International and national scientists have defined lower altitude of Nepal as one of the centers of origin of Basmati rice. Many Nepalese basmati rice landraces have been characterized and evaluated using morphological traits, isozymes and DNA markers. Four basmati type of rice landraces have been registered in National Seed Board. Many community seed banks have maintained different types of Basmati rice landraces. National Agriculture Genetic Resources Center and International genebanks have collected more than 80 and conserved 68 basmati landraces. Basmati rice landraces have geo-linked traits. The historical culture of production, consumption and marketing of native basmati rice in Nepal should always be favored by both national and international rules and regulations. Nepal has ample and valid evidences to get geographical indication (GI) right on Basmati rice
Isolation, Identification and Screening of Bacillus species with Antimicrobial Activity from Different Soil Samples of Kathmandu Valley
Full text linkBacillus species are one of the predominant soil bacteria that are able to produce essential secondary metabolites that have antagonistic effects on other microorganisms. They are Gram-positive, endospore-forming, chemoheterotrophic, aerobic or facultative anaerobic rods usually consisting of peritrichous flagella for motility. The major aim of this study was to isolate the antimicrobials producing Bacillus spp. from soil samples of different parts of the Kathmandu Valley, identify them and to assess their antimicrobial activity against different pathogenic bacteria. The test organisms used were Staphylococcus aureus (ATCC 25923), E. coli (ATCC 25922), Pseudomonas spp., Salmonella spp., methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum beta-lactamase (ESBL) producing E. coli. Twenty four isolates from 9 soil samples identified as Bacillus spp. showed the zone of inhibition around their growth on Nutrient agar during isolation. These 24 isolates were chosen for primary screening of production of antimicrobial by perpendicular streaking method using four test organisms. . Of these 24 isolates, six isolates showing a significant zone of inhibition (≥1mm) against two or more test organisms from the primary screening were chosen for secondary screening which was further tested with six test organisms including ESBL E.coli and MRSA. They were further characterized through different physiological and biochemical tests. All 6 isolates showed inhibitory action against MRSA and the largest zone of inhibition (30mm) was shown by isolate U6. Isolate U3 was found to have broad spectrum antimicrobial activity with inhibitory effect against gram negative organisms- Pseudomonas and Salmonella and gram positive organism S. aureus (ATCC 25923). Isolate U5 showed a zone of inhibition of about 25mm against S. aureus which was comparable to that of erythromycin. Hence, this study determines the soil in Kathmandu Valley as a potential source of antimicrobial producing Bacillus spp. and recommends isolation and further characterization of Bacillus isolates as a possible source of novel drug to combat with the emergence of multidrug resistant strains
Screening of Potential Plant Growth Promoting Properties of Bacillus Species Isolated from Different Regions of Nepal
Full text linkThe deleterious effects of intensive use of chemical fertilizers and pesticides in agriculture has led to the substantial research efforts on finding the alternatives to these agrochemicals. This study was aimed to isolate Bacillus species from soil of different regions of Nepal and screen for their ability to promote plant growth directly or indirectly by testing their ability to produce plant growth hormone indole acetic acid, hydrogen cyanide, ammonia and protease as well as phosphate solubilization. Thirty nine Bacillus strains were isolated from 25 soil samples of different regions of Kathmandu and Chitwan districts of Nepal. These isolates were tested for plant growth promoting traits in vitro. Among the total isolates, about 48.7% were indole acetic acid producers, 38.4% of the isolates showed the ability to solubilize the phosphate, 71.8% were able to produce ammonia and all the isolates had the ability to produce hydrogen cyanide and protease. The isolated strains showed positive results to maximum PGPR traits and exhibited a potential to be used as alternatives to chemical fertilizers and pesticides and could be used as low-cost bio-based technology to promote plant growth in the agricultural sector
Thyroid Function and Thyroglobulin Level in Iodine-Deficient Children of Eastern Nepal
Full text linkIodine deficiency during childhood affects physical and mental development. Iodine deficiency or excess both can negatively impact thyroid function. We conducted this study to assess iodine nutrition and thyroid function in children with insufficient urinary iodine concentration. A community-based cross-sectional study was conducted among the selected schools of Udayapur district. Urinary iodine concentration (UIC) was measured in 1012 school children (6-14 years). Based on UIC data, 83 blood samples were collected to measure serum thyroglobulin (Tg), thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4). UIC was measured by ammonium persulfate digestion method, and Tg, TSH, fT4, and fT3 were measured using ELISA kits. The median UIE was 236 µg/L, and 11.1% of the children had insufficient UIC. The mean fT3, fT4, and TSH in children with insufficient UIC were 2.55±0.43 pg/mL, 0.96±0.28 ng/dL, and 3.60±1.44 mIU/L respectively. Among children with low UIC levels, the median Tg was 17.5 ng/mL. Overt hypothyroidism was seen in 6%, and subclinical hypothyroidism in 3.6%. The children had sufficient iodine nutrition, and the frequency of thyroid dysfunction was low among the children with insufficient UIC
Microbial and Physico-Chemical Quality Assessment of Rivers of Kathmandu Valley
Full text linkWater quality refers to the chemical, physical, biological characteristics of water. It is a measure of condition of water relative to requirement of one or more biotic species and or to any human need or purpose. The main objective of the study is to detect the physio-chemical and microbiological parameters of water sample from the Bagmati river and its tributaries of Kathmandu valley along with antibiotic susceptibility. In physico-chemical parameters, turbidity, temperature, pH, Electrical conductivity, Dissolved Oxygen, Biological Oxygen Demand, Ammonia, Alkalinity, Hardness, Chloride, Phosphate, Iron, Nitrate, Total Dissolved solids, and color were analyzed. Iron and Turbidity was found to be above the World health organization and Nepal Standard guideline in all the samples (100%), while Ammonia was found to be above the WHO guideline in 10(90%) samples. Among 11 samples, 10(90%) showed a low Dissolved oxygen level. Most Probable Number method was followed for counting total load of coliform and fecal coliform. Escherichia coli was isolated from the sample and subjected to Antibiotic susceptibility. Coliform was detected in all the samples and E. coli was identified as highly resistant towards Gentamicin (81.8%) and sensitive towards Chloramphenicol (81.8%). High value of ammonia, turbidity and low value of Dissolved Oxygen in the lower belts of river was due to large inputs of wastewater and organic loads caused by anthropogenic activities. High value of Coliform in all the samples indicates bacterial contamination in river water. The comparative study for the water quality variables in the urban areas showed that the main rivers and its tributaries were equally polluted
Potential surface active agent production using very low grade and cheap substrate by Bacillus subtilis as microbial cell factory
Full text linkBio-surfactants are surface-active molecules which are produced by the wide range of microbes including bacteria, fungi, moulds, and yeast. This study was conducted to identify bio-surfactants by Bacillus subtilis combined with use of cheap substrates and industrial wastes (Mustard cake, Whey and Soya cake) which are found locally in Nepal. Bacillus subtilis, one of the most potential bio-surfactants producer; was isolated from soil sample of hydrocarbon contaminated site. Isolates were grown in a Minimal Salt Media (MSM) with 10% (v/v) mustard oil cake, whey and soya cake separately. The presence and potential of surfactant was determined by the oil spreading technique, emulsification index (%E24) and surface tension measurement. It was revealed that the surface tensions of cell free extract were 54.41, 60.02 and 56.64 mN/m for from mustard cake, whey and soya cake respectively as compared to distilled water (72.09) at 25oC. The emulsification index values was found to be highest in engine oil from the bio-surfactant extracted from mustard cake, soya cake and whey respectively. Similarly, mustard oil showed the lowest value of emulsification index. The highest emulsification activity was shown in mustard oil i.e. 1.13 from the cell free extract from mustard oil and lowest in engine oil i.e., 0.07, by the extract from soya cake medium, when measured in spectrophotometer at 540 nm. In conclusion, strain of Bacillus subtilis was found to be the potential surface active agent producers on the mustard oil cake, which can be useful medium for various environmental, food, medicinal and industrial processes
Phenolic Compounds from the Aerial Parts of Adenophora triphylla (Thunb.) A. DC. var. triphylla and their Free Radical Scavenging Activity
Full text linkAdenophora triphylla (Thunb.) A. DC. var. triphylla (Family: Campanulaceae) is distributed in Japan, Korea, and China. It is locally known as “Saiyousyajin” in Japan and the roots are used in traditional medicine to treat chronic bronchitis and whooping cough, and also as anti-inflammatory and anti-tussive agents. Till now, there is no report on the chemical constituents of aerial parts. Thus, the main aim of this study was to isolate and identify major chemical constituents of aerial parts of A. triphylla var. triphylla, and to evaluate their free radical scavenging activity. The 70% methanol extract of the aerial parts was subjected to repeated column chromatography using MCI gel CHP-20P, Sephadex LH-20, ODS and silica gel columns to isolate the five phenolic components (1-5). Free radical scavenging activity of the extract and compounds was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity method. The structures of the isolated compounds were elucidated as luteolin (1), luteolin 4’-O-b-glucopyranoside (2), luteolin 7-O-b-glucopyranoside (3), luteolin 7-O-neohesperidoside (4) and chlorogenic acid (5) based on their nuclear magnetic resonance (NMR) spectral data and comparison with literature values. All these compounds were isolated for the first time from A. triphylla var. triphylla. Extract showed weak free radical scavenging activity. Among isolated compounds, luteolin (1), luteolin 7-O-b-glucopyranoside (3), luteolin 7-O-neohesperidoside (4) and chlorogenic acid (5) showed potent free radical scavenging activity. Results from this study suggest that the aerial parts of A. triphylla var. triphylla might be a potential plant source for the development of functional foods, however further detailed research is necessary
Study of the Impact of Organic Manures and Biofertilizers on growth of Phaseolus aureus Roxb.
Full text linkWeed 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