Tackling the COVID-19 Pandemic- A Review

Since December 2019, a new type of coronavirus called novel coronavirus (2019-nCoV, or COVID-19) was identified in Wuhan, China and on March 11, 2020, the World Health Organization (WHO) has declared the novel coronavirus (COVID-19) outbreak a global pandemic. With more than 101,797,158 confirmed cases, resulting in 3,451,354 deaths as of May 21, 2021, the world faces an unprecedented economic, social, and health impact. The clinical spectrum of COVID-19 has a wide range of manifestations, ranging from an asymptomatic state or mild respiratory symptoms to severe viral pneumonia and acute respiratory distress syndrome. Several diagnostic methods are currently available for detecting the coronavirus in clinical, research, and public health laboratories. Some tests detect the infection directly by detecting the viral RNA using real time reverse transcriptase polymerase chain reaction (RT-PCR) and other tests detect the infection indirectly by detecting the host antibodies. Additional techniques are using medical imaging diagnostic tools such as X-ray and computed tomography (CT). Various approaches have been employed in the development of COVID-19 therapies. Some of these approaches use drug repurposing (e.g. Remdesivir and Dexamethasone) and combinational therapy (e.g. Lopinavir/Ritonavir), whilst others aim to develop anti-viral vaccines (e.g. mRNA and antibody). Additionally, health experts integrate data sharing, provide with guidelines and advice to minimize the effects of the pandemic. These guidelines include wearing masks, avoiding direct contact with infectious people, respiratory and personal hygiene. Taken together, an extensive knowledge on transmission mechanisms, clinical spectrums, specific diagnostics methods, host-virus interactions are required to tackle this pandemic. J. Bio-Sci. 29(2): 175-186, 2021 (December)

Cytotoxicity Assessment of Heritiera Littoralis (Aiton), Madhuca Longifolia (König) Macbr., Nerium Indicum Mill. And Sapium Indicum (Willd.) Leaves on Artemia Salina (L.)

Petroleum ether, CHCl3 and CH3OH extracts of leaves of Heritiera littoralis (Aiton), Madhuca longifolia (König) Macbr., Nerium indicum Mill. and Sapium indicum (Willd.) were subjected to assess cytotoxicity against Artemia salina (L.) nauplii. The petroleum ether extract of H. littoralis leaves showed LC50 values 273.77, 97.27, 51.60, 37.12, 14.60 and 12.59 ppm after 12, 18, 24, 30, 36 and 42 h; the CHCl3 extract showed LC50 values 733.25, 105.51, 40.72 and 18.20 ppm after 6, 12, 18 and 24 h whereas CH3OH extract showed 73.05, 30.62, 24.56, 20.85, 16.21 and 6.71 ppm after 6, 12, 18, 24, 30 and 36 h of exposure respectively. The petroleum ether extract of M. longifolia leaves possess LC50 values 259.35, 115.17, 56.84 and 8.73 ppm after 12, 18, 24 and 30 h; the CHCl3 extract possess LC50 values 585.43, 205.86, 112.74, 75.62, 52.84and 47.34 ppm after 12, 18, 24, 30, 36 and 42 h but CH3OH extract possess LC50 values 185.87, 60.70, 30.11 and 15.39 ppm after 12, 18, 24 and 30 h of exposure respectively. The petroleum ether extract of N. Indicum leaves recorded LC50 values 249.82, 146.07, 80.23, 54.21 and 40.19 ppm after 18, 24, 30, 36 and 42 h; the CHCl3 extract gave LC50 values 36.13, 21.72, 19.03, 16.81 and 16.34 ppm after 12, 18, 24, 30 and 36 h but CH3OH extract recorded LC50 values 394.90, 129.69, 81.50, 73.10 and 37.51 ppm after 18, 24, 30, 36 and 42 h of exposure respectively. Similarly, the petroleum ether extract of S. indicum leaves showed LC50 values 24.79, 13.18 and 4.61 ppm after 12, 18 and 24 h; the CHCl3 extract were 50.45, 42.64, 21.20 and 14.93 ppm after 18, 24, 30 and 36 h of exposure and the CH3OH extract showed LC50 values 306.37, 217.18, 149.38, 73.52, 54.45 and 22.91 ppm after 12, 18, 24, 30, 36 and 42 h of exposure respectively. The intensity of efficacy of the extracts could be arranged in the following descending order of S. indicum (petroleum etroleum ether extract) >H. littoralis (CH3OH extract) >M. longifolia (petroleum ether extract) >N. indicum (CHCl3 extract). J. Bio-Sci. 29(2): 139-149, 2021 (December)

Effect of Two Essential Oils From the Asteraceaes Family Against Ectomyelois Ceratoniae Zell. (Lepidoptera, Pyralidae): Case Of Artemisia Herba-Alba Asso. And Artemisia Compestris L.

The current work was done Artemisia herba-alba and Artemisia compestris essential oils harvested from the Eastern Algerian Sahara, their insecticidal characteristics against the eggs and adults of the date moth Ectomyelois ceratoniae. Indeed, two treatment modes were used; by contact application on eggs and by inhalation against adults. It appears from the results that the hatch rates were less than the hatching rate recorded in the control (96% ±00.00). The hatching rate reported on eggs treated by the highest dose (160 μl/ml) of Artemisia herba-alba and Artemisia compestris essential oils are 16.66 ± 08.81 and 37.77 ± 13.47 respectively. Statistical treatment results by the Chi-square test (χ2), attest that the treatment by A. herba-alba and Artemisia compestris essential oils at the same dose (160 μl/ml) affect significantly (χ2 = 35.62, p = 0.00 and χ2 = 21.17, p = 0.00 respectively) the hatching rate compared to the control. The sensitivity of adults to essential oils is expressed by 100% mortality rates obtained after 10 min of treatment by the highest doses (80 μl/ml and 160 μl/ml) of A. herba-alba essential oils, the same mortality rates (100%) were notified with the same doses (80 μl/ml and 160 μl/ml) after 20 min and 15 min of treatment by Artemisia compestris essential oils respectively. The dose-dependent mortality data revealed that there was a significant difference between the five doses of A. herba-alba essential oil tested except at the last treatment time (20 min) for which it was appeared p = 0.571, while for A. compestris essential oil, a significant difference was recorded with p varying between 0.00 and 0.003. The lowest LD50 value (0.09 μl/ml and 16.71 μl/ml) were noted during the longest treatment time (20 min), while the highest LD50 value (75.85 μl/ml and 263.7 μl/ml) were found during the shortest time (5 min) of A. herba-alba and A. compestris respectively. J. Bio-Sci. 29(2): 09-17, 2021 (December)

Inclusive Scenario of Natural Products Obtained From Agar Plant (Aquilaria SP.) In Bangladesh- A Review

Agarwood is the resinous heartwood obtained from the injured parts of trees under Thymelaeaceae family particularly from Aquilaria species. Agarwood is considered as the most prized non-timber forest product (NTFP) used in attars as well as medicines. Quality of agarwood is the determiner for defining its commercial value. Different countries use different grading system to explain the quality of agarwood. In Bangladesh, more than 45 compounds have been identified so far, mostly sesquiterpenoids, alkanes, fatty acid and other volatile aromatic compounds that are responsible for its fragrance and high prices. Ether extract, total phenolic contents, flavonoid, antioxidant and microbiological tests have shown tremendous positive results. Chemical profiling of agar products is the best identified using GC-MS technique by the various authors. Present review discusses the full scenario of Aquilaria production, inoculation, extraction methods, determination of agarwood quality and chemical constituents of agar oils and possibilities and barriers of this industry in Bangladesh. J. Bio-Sci. 29(2): 151-173, 2021 (December)

Response of Chickpea (Cicer Arietinum L.) To Boron and Molybdenum Fertilization

An experiment was conducted to study the effect of micronutrients on the growth and yield performance of chickpea. The experiment was consisted using two factors- variety and treatments. Two local cultivars viz. BARI Chola-5 and BARI Chola-9 and five treatments e.g. T0 = control, T1 = 2 kg B/ha, T2 = 2 kg Mo/ha, T3= seed priming with Mo (1g/l water), T4 = foliar spray of B (0.5 g/l water) + seed priming with Mo (1g/l water), and T5 = 2 kg B/ha + seed priming with Mo (1g/l water) were considered for this study. A randomized complete block design (RCBD) was adopted with three replications. Significant variation was observed between the varieties and here the BARI Chola-9 produced the higher seed yield (2.47 ton/ ha). Treatment showed significant effect on the yield attributes and yield of chickpea. The highest plant height, number of branches/ plant, number of pods/ plant, nodule/ plant, number of effective pod/ plant, length of the pod, 1000-grain weight, seed yield, straw yield, biological yield was obtained from T4. The highest seed yield (2.68 ton/ ha) was recorded from BARI Chola-9 with foliar spray of boron and seed priming with Mo. The results indicated that foliar spray of B and seed priming with molybdenum can be beneficial in improving growth and yield of chickpea variety BARI Chola-9. J. Bio-Sci. 29(2): 43-51, 2021 (December)

Correlation Between Oxidative Stress Generation, Reticular Fiber Density and Testicular Histomorphometric Parameters Of Streptozotocin-Induced Diabetic Wistar Rat

The actual underlying mechanism of alterations in testicular histomorphometric parameters resulting from diabetes-induced oxidative stress is still not well understood because of the absence of supporting evidence from scientific experiments. This study was conducted to investigate the correlation between serum oxidative stress markers with testicular histomorphometric parameters and reticular fiber density of Streptozotocin-induced diabetic Wistar rat. The experiment included twenty eight adult male rats sorted into four groups, Group A (Control), other animals were sorted into treatment groups based on their blood glucose levels after inducing diabetes with 65 mg/kg/bw of streptozotocin, Groups B (100 - 200 mmol/l), Group C (210 - 250 mmol/l), Group D (260 - 300 mmol/l). At termination, Serum superoxide dimutase (SOD), catalase and melondialdehyde where evaluated using reagent based antioxidant enzyme assay while reticulum stain kits was used to demonstrate for reticular fiber density. Histomorphometric measurements were carried out using ocular micrometer after calibration on a light microscope. Statistical analysis was done using analysis of variance with p<0.05 considered significant. Results reveal that the higher the blood glucose levels in diabetic animals, the higher the serum concentration of oxidative stress markers. Density of reticular fiber increased with increase in blood glucose levels, while tubular diameter and epithelial height decreased with increase in increase in hyperglycaemic levels. In conclusion, there was a progressive increase in reticular fiber density and decrease in tubular diameter and epithelial height as a consequence of increase oxidative stress generation in diabetic model. J. Bio-Sci. 29(2): 01-08, 2021 (December)

Quantification of Heavy Metal Accumulation in Water and Edible Fish Tissue Samples Collected From the River Tawi, Jammu, India

The present study estimated the concentration (in ppm) of heavy metals of Zn, Fe, Cu and Pb in water samples and edible tissue of Labeo boga; both collected from the non polluted (Station I) and polluted (Station II) locations of river Tawi, Jammu, India. The mean concentration of heavy metals (Zn, Fe, Cu, Pb) at Station I were 0.048±0.008 (ppm); 0.016±0.001 (ppm); 0.157±0.002 (ppm) and 0.0001±0.0001 respectively; while at Station II, these values were 0.133±0.001 (ppm); 0.022±0.002 (ppm); 0.206±0.002 (ppm) and 0.002±0.001 (ppm) respectively; the statistical difference between the stations were significantly higher (p<0.05). The order of heavy metal load obtained in water samples at both the stations was found to be Fe>Zn>Cu>Pb. Also, the mean bioaccumulation of heavy metals viz. Zn, Fe, Cu and Pb in the edible tissue of fish at Station I was found to be 0.374±0.011 (ppm), 0.105±0.02 (ppm); 0.094±0.04 (ppm) and0.001±0.0001 (ppm) respectively; on the other hand, mean bioaccumulation was 0.539±0.013 (ppm); 0.156±0.04 (ppm); 0.121±0.023 (ppm) and 0.0013±0.0001 (ppm) respectively at Station II. Even though bioaccumulation of the heavy metals in the experimental sites did not exceed the acceptable limits recommended by the agencies like FAO and WHO, the present results showed an increasing trend of the accumulation, which definitely poses a serious threat to the survival of aquatic organisms in the study area. J. Bio-Sci. 29(2): 19-29, 2021 (December)

Effects of Osmotic, Thermal and Plant Growth Regulators Seed Priming on Different Wheat Varieties

Proper germination and proper growth of seedlings in conventional farming methods are often not achieved at the desired rate. The purpose of priming is to reduce germination time and improve stand and percentage of germination and increases vigour for fast and strong plant development. In order to evaluate the effect of seed priming on growth and yield of wheat the present study was conducted at Agronomy Farm House, Rajshahi University. Three wheat varieties (BARI Gom-24, BARI Gom-25 and BARI Gom-26) were tested with three groups of priming media (osmo-priming, thermos-priming and plant growth regulator priming) and control (non-soaked). Seeds were primed for 24 h at 25°C with four priming media, osmo-priming (1% NaCl, 2% KNO3, 2% KH2PO4, and 10% PEG), PEG-Priming (50 μM GA3 and 50 μM BAP) and thermo-priming (0°C, 5°C and 10°C) and control was without priming agent. All types of priming media were significantly different among their types for plant height (cm), tiller number and dry biomass (g). PEG was significantly different in osmo-priming, GA3 was significantly different in PGR-priming and 0°C was significantly different in thermo-priming. In case of vigor index, 2% KH2PO4 was suitable among osmo-priming, GA3 was better than BAP priming and 0°C was optimum among all temperature priming. Seed priming helps seeds to grow rapidly and evenly in the field, producing healthier and faster maturing crops with better yields. J. Bio-Sci. 29(2): 111-122, 2021 (December)

In Vitro and in Vivo Evaluation Of Pharmacological Activites of Pouzolzia Sanguinea

Pouzolzia sanguinea grows in tropical and sub-tropical regions of Bangladesh, used for a variety of purposes including pain, rheumatoid kidney diseases in traditional medicine. The crude ethanolic leaf extract of P. sanguinea with its different fractions (ethanol, n-hexane, and chloroform) was investigated for phytochemical constituents, in vitro antioxidant, anti-inflammatory effects, in-vivo analgesic and antipyretic activities. Preliminary phytochemical constituents were identified by chemical group test. P. sanguinea fractionated extracts contain alkaloids, glycosides, tannins, flavonoids, saponins, gums, and amides. Antioxidant activity test was performed by both qualitative (TLC and Rf value) and quantitative tests (inhibition of DPPH free radical scavenging). Extracts exhibited significant (p <0.001, p <0.0001) inhibition of DPPH free radical scavenging activity as compared to the standard drug ascorbic acid at similar doses. In vitro anti-inflammatory activity was determined by protein denaturation of egg albumin method. The percent inhibition of protein denaturation in the experiment of ethanol extract was found significantly higher (p <0.0001) compared with chloroform and n-hexane extracts. In addition, in vivo analgesic and antipyretic effects were determined in mice by acetic acid-induced writhing and yeast-induced pyrexia methods. The ethanol extracts of P. sanguinea exhibited inhibition of writhing reflex on mice by 71.58% at the dose of 500 mg/kg body weight which had greater analgesic activity than other n-hexane and chloroform extracts. In the anti-pyretic test, fractional extracts ethanol, chloroform, and n-hexane at a dose of 500 mg/kg body weight significantly (p <0.05) decreased pyrexia in mice up to 3 h as compared with the positive control paracetamol drug at a dose of 150 mg/kg body weight. In our in vitro and in vivo study models, it is evident that Pouzolzia sanguinea fractionated extracts showed significant antioxidant, anti-inflammatory, analgesic, and antipyretic activities. J. Bio-Sci. 29(2): 31-42, 2021 (December)

Interphase Nuclear Structure in Ten Species of Pteridophytes

In thelypterids, interphase chromosomes of Ampelopteris prolifera were accompanied by two or three nucleoli. One nucleolus was seen floating outside the nucleus while other remained attached with the nucleus in annular cells of Christella arida. The mean of chromocentres determined in Adiantum species ranged from 49.8 to 53.6, whereas, it ranged from 46.6 to 49.5 in Pteris species. On the other hand, the value for chromocentres ranged from 62.5 to 123.5 in thelypterids. Nuclear organization was observed to be chromocentric type. In case of interphase nuclear volume it was observed that in Adiantum it was highest in A. capillus-veneris followed by A. caudatum and A. lunulatum, in Pteris it was highest in P. biaurita followed by P. vittata and P. griffithi, and in case of thelypterids, it was highest in C. dantata followed by C. Cylindrothix, A. Prolifera and C. arida. J. Bio-Sci. 29(2): 93-98, 2021 (December)