Enhancing Immunological Memory: Unveiling Booster Doses to Bolster Vaccine Efficacy Against Evolving SARS-CoV-2 Mutant Variants.

A growing number of re-infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in previously immunized individuals has sparked discussions about the potential need for a booster vaccine dosage to counteract declining antibody levels and new strains. The protective immunity produced by vaccinations, and past illnesses relies on immunological memory. CD4 + T cells, CD8 + T cells, B cells, and long-lasting antibody responses are all components of the adaptive immune system that can generate and maintain this immunological memory. Since novel mutant variants have emerged one after the other, the world has been hit by repeated waves. Various vaccine formulations against SARS-CoV-2 have been administered across the globe. Thus, estimating the efficacy of those vaccines against gradually developed mutant stains is the essential parameter regarding the fate of those vaccine formulations and the necessity of booster doses and their frequency. In this review, focus has also been given to how vaccination stacks up against moderate and severe acute infections in terms of the longevity of the immune cells, neutralizing antibody responses, etc. However, hybrid immunity shows a greater accuracy of re-infection of variants of concern (VOCs) of SARS-CoV-2 than infection and immunization. The review conveys knowledge of detailed information about several marketed vaccines and the status of their efficacy against specific mutant strains of SARS-CoV-2. Furthermore, this review discusses the status of immunological memory after infection, mixed infection, and vaccination.

Antibacterial potency of cytocompatible chitosan-decorated biogenic silver nanoparticles and molecular insights towards cell-particle interaction.

In the study, leaf extract of Carica papaya was utilized for the biogenic fabrication process of chitosan functionalized silver nanoparticles (Ag-Chito NPs). HRTEM analysis revealed that the fabricated Ag-Chito NPs was spherical in shape, with an average particle size of 13.31 (±0.07) nm. FTIR, UV-Vis, DLS, and other characterizations were also performed to analyze the diverse physicochemical properties of the particles. The antibacterial potency of the synthesized Ag-Chito NPs was tested against the two clinically isolated multidrug resistant uropathogenic bacterial strains, i.e. MLD 2 (Escherichia coli) and MLD 4 (Staphylococcus aureus) through MIC, MBC, time and concentration dependent killing kinetic assay, inhibition of biofilm formation assay, fluorescence and SEM imaging. Significantly, Ag-Chito NPs showed the highest sensitivity against the MLD 2 (MIC value of 12.5 µg/mL) strain, as compared to the MLD 4 (MIC value of 15 µg/mL) strain. From the hemolysis assay, it was revealed that Ag-Chito NPs exerted no significant toxicity up to 50 µg/mL against healthy human blood cells. Additionally, in silico analysis of chitosan (functionalized on the surface of AgNPs) and bacterial cell membrane protein also evidently suggested a strong interaction between Ag-Chito NPs and bacterial cells, which might be responsible for bacterial cell death.

Alteration of dietary habits and lifestyle pattern during COVID-19 pandemic associated lockdown: An online survey study.

BACKGROUND & AIM: A few population-based studies have looked at how the Corona virus disease (COVID-19) pandemic and outbreak-related lockdown has impacted people's daily eating habits and lifestyles. Due to the emergence of the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2), continuous lockdown or social isolation can alter dietary consumption patterns and lifestyle routines, resulting in significant negative health consequences. Focused on the COVID-19 and disease related lockdown effects, this study aims to reflect the evolving trend in dietary habits and lifestyle status during the COVID-19 lockdown in West Bengal through a population mediated retrospective survey distributed via social media platforms. METHODS: This survey was conducted using Google form via online platform from July 7 to July 31, 2020, with 1059 participants reported their eating habits and lifestyle preferences, as well as basic socio-demographic details. Entire variables were qualitatively examined and uttered as frequency (f) and percentage (%). The Chi-square test was performed to conclude whether categorical variables differed. RESULTS: A high number of participants reported that they were consumed healthy foods and physically active during this pandemic situation. Females were more likely to be involved in exercise and consume protein-rich food, as well as the majority of them, maintain basic dietary and Ayurvedic home remedies precautions like consumption of lemon, consumption of herbs, taking warm water, etc. A majority of older participants were tried to maintain a healthy lifestyle with extra protective essential protection during the COVID-19 stage. The frequency of going to market was decreased by the participants. Females were more likely to decrease their frequency of going to market than males. In terms of hygiene and sanitization of food items after buying from the market, females were more careful than males. Participants with higher education were more likely to be careful regarding the hygiene of food preparation and eating during this situation. CONCLUSION: From this study, dieticians, legislators, and public health experts can have a better understanding of the current situation of food intake and lifestyle trends in communities of West Bengal, India. It also has the potential to have a significant impact on future public health research.

Awareness, knowledge and acceptance of COVID-19 vaccine among the people of West Bengal, India: A web-based survey.

Objectives: Rapid vaccination is the only way to fight against COVID-19.Vaccine hesitancy is the major barrier against this strategy. The main objective of this cross-sectional study was to analyze COVID-19 vaccine acceptance in the general population of West Bengal (India), as well as to investigate the factors that were independently associated with people's desire to receive the vaccine. Methods: An online questionnaire was distributed by email, Whatsapp, and other social media platforms, and the responses were analyzed using the SPSS (Version 20) software. Results: We conducted a web-based survey in West Bengal, India (N = 803), and accumulated information on individuals' desire to adopt vaccine against COVID-19, views about the virus's effectiveness, and many knowledge-based socio-demographic factors that potentially impact the overall vaccination efforts. We found that, 12.08% of participants do not believe that vaccination against COVID-19 is necessary, but among the rest of the population, 44.33% of individuals are willing to be vaccinated once the vaccine is available, whereas 39.60% of the population responded that they will not be vaccinated immediately but will do so later. Conclusions: Despite the participants' strong vaccine willingness, our findings revealed a troubling degree of lake of awareness and insignificant scientific knowledge about the COVID-19 pandemic and its associated vaccination programme. Vaccination hesitancy is not a barrier in this survey region, but poor vaccine availability and a lack of awareness campaigns may instill unfavorable beliefs in those who refuse to be vaccinated.

OBJETIVOS: La rapidez de la vacunación es el único modo de luchar contra la COVID-19. Las dudas sobre la vacuna constituyen la mayor barrera contra esta estrategia. El objetivo principal de este estudio transversal fue analizar la aceptación de la vacuna contra la COVID-19 en la población general de Bengala occidental (India), así como investigar los factores asociados de manera independiente al deseo de recibir la vacuna por parte de las personas.Métodos: Se distribuyó un cuestionario online por correo electrónico, Whatsapp, y otras plataformas de redes sociales, y se analizaron las respuestas utilizando el software SPSS (Versión 20). RESULTADOS: Realizamos una encuesta basada en web en Bengala occidental, India (N= 803), y acumulamos la información sobre el deseo de las personas de recibir la vacuna contra la COVID-19, las opiniones sobre la efectividad del virus, y muchos factores sociodemográficos basados en el conocimiento que tienen un impacto potencial en los esfuerzos globales sobre vacunación. Encontramos que el 12,08% de los participantes no creen en la necesidad de la vacunación contra la COVID-19 pero, entre el resto de la población, el 44,33% de los individuos desean ser vacunados una vez que se disponga de la vacuna, mientras que el 39,6% de la población respondió que no se vacunarían de inmediato, aunque lo harían más adelante. CONCLUSIONES: A pesar de la sólida voluntad de los participantes por la vacuna, nuestros hallazgos revelaron un grado preocupante de falta de concienciación y conocimiento científico insignificante acerca de la pandemia de COVID- 19 y su programa de vacunación asociado. Las dudas sobre la vacuna no son una barrera en la región de esta encuesta, pero la poca disponibilidad de la vacuna y la falta de campañas de concienciación puede infundir creencias desfavorables en aquellas personas que rechazan recibir la vacuna.

Advancements in Adjuvanticity of Bioactive Inorganic and Organic Compounds.

BACKGROUND: Regardless of the enormous success of vaccines over decades, the formulation of biocompatible and highly effective vaccines is still insufficient for combating new pathogens. DISCUSSION: The degree of effectiveness of any vaccine largely depends on the choice of appropriate adjuvant. Along with the optimum biocompatibility, an ideal adjuvant must be biodegradable, economical and easy to manufacture. To date, various organic and inorganic substances have been used as an adjuvant to augment the effectiveness of the vaccine. Immunological adjuvants are essential for strong and long-term effects against various pathogens. However, a very limited number of licensed adjuvants are available for the formulation of a successful vaccine. This leads to a challenging situation in medical science. CONCLUSION: The present review concisely summarizes the mechanism of action of various bioactive organic and inorganic immunological adjuvants, their limitations and future perspectives for their appropriate modification. Current trends of anticancer therapies using immunological adjuvants have also been highlighted in this review.

Tuberculosis related stigma attached to the adherence of Directly Observed Treatment Short Course (DOTS) in West Bengal, India.

BACKGROUND: Stigma is a major barrier to the successful completion of the Directly Observed Treatment Short Course (DOTS). People put on DOTS have to face repeated exposure to stigma as per the requirement of the treatment. Thus stigma can shape the extent of access and adherence to treatment. But there is very little information available in Indian context explaining the extent of association between the stigma perceived among the patients and adherence to their DOTS therapy. AIM: To explore the level of stigma perceived by the persons with TB and its influence on the adherence to DOTS treatment. METHODS: A cross sectional epidemiological study was conducted among 145 DOTS defaulters from three randomly selected districts in West Bengal. Respondents were approached at their households. Information was collected using a pretested questionnaire. Adherence to DOTS was grouped as early default (continued DOTS from 0 to 30 days) and late default (continued DOTS > 30). Stigma score was assessed using 11 item questions. Stigma score was grouped as low level (0-23) and high level (24-44). Analysis was done using Chi-square and multivariate logistic regression models to identify factors to influence adherence to DOTS. SPSS 23.0 version statistical software was used for analysis. RESULTS: Mean stigma score for the state was 23.0. Total 51 (40.69%) persons were within the low stigma group and 94 persons (59.31%) were within high stigma score group. District wise mean score was 19.8, 22.8 and 24.5 respectively for Birbhum, Jalpaiguri and North 24 Parganas. In North 24 Parganas, the high stigma score group accounted for 85.5% compared to 35.9% in Birbhum. Among the low stigma group, late default was 52.1% compared to 66.7% in high stigma group (p = 0.054). People with lower stigma level were 8.59 times more likely to have late default than the people with higher stigma level (p = 0.001). CONCLUSION: Perceived stigma among the patients was identified as an important predictor for the adherence to DOTS therapy. Stigma reduction strategy should be designed to improve adherence to DOTS therapy. Present study recommends in-depth qualitative research to get more insight on the extent and shape of stigma and the way it influences the adherence. Apart from the stigma of the patients, influence of community stigma is a gray area for further research.

Tuberculosis related stigma and its effect on the delay for sputum examination under the Revised National Tuberculosis Control Program in India.

BACKGROUND: One major barrier to achieve goal of tuberculosis (TB) control program globally, is the stigma attached to the disease. Perceived stigma can delay sputum test in time. Delay will lead to spread of infection in the community. There is no scientific information available in India exactly looking into the association between delay in sputum examination and stigma. AIM: We conducted a study in rural West Bengal among persons with cough for 2 weeks or more to assess their level of stigma, its influence on delay for sputum test and identify factors those shape the level of stigma. METHODS: A community based cross sectional survey was conducted from February to June 2015 in West Bengal, India. We interviewed 135 persons of 15-60 years. Data were collected using a pretested structured questionnaire. Chi-square and logistic regression analysis were done using SPSS 23.0 statistical software. RESULTS: Among the 'lower stigma' group (score 4-24), 'delay' (14-25 days) is found among 46.2% respondents and 'much delay' (26-120 days) among 53.8%. Among the 'higher stigma' (score 25-36) group, 'delay' is found among 20.5% respondents and 'much delay' among 79.5%. Persons with lower stigma are 0.17 times likely to delay than persons with higher stigma [adjusted odds ratio (AOR): 0.17 (0.044-0.668), p=0.011)]. Important influencers of stigma are caste [AOR: 5.90 (1.66-20.90), p=0.006], number of family members [AOR: 3.46 (1.08-11.06), p=0.009] and residence in urban or rural [AOR: 3.97 (1.03-15.27), p=0.045]. CONCLUSION: Revised National Tuberculosis Control Program in India should de-stigmatize the community giving priorities to lower castes, big families and rural areas.

Management of experimental hypochlorhydria with iron deficiency by the composite extract of Fumaria vaillantii L. and Benincasa hispida T. in rat.

The aim of the present study was to search the effective ratio of whole plant of Fumaria vaillantii Loisel (Fumaria vaillantii L.) and fruit of Benincasa hispida Thunb. (Benincasa hispida T.) in composite form, namely "FVBH" for the management of hypochlorhydria along with iron deficiency in male albino rats. Hypochlorhydria refers to suppression of hydrochloric acid secretion by the stomach. Hypochlorhydria was induced by ranitidine in this study. We used four composite extracts of the mentioned plant and fruit with different ratios (1:1, 1:2, 2:1, and 3:2) for searching the most effective composite extract for the correction of hypochlorhydria. Gastric acidity is an important factor for iron absorption. Thus, hypochlorhydria causes iron deficiency in rat and it was prevented significantly by the extract treatment at the ratio of 1:1 of the said plant and fruit. The correction of iron deficiency by the composite extract was compared with iron supplementation to hypochlorhydric rat. It was found that preadministration followed by coadministration of FVBH-1 (1:1) able to prevent the ranitidine-induced hypochlorhydria and iron deficiency. The composite extract, FVBH-1 (1:1) significantly (P<0.05) increased the pepsin concentration, chloride level in gastric juice, iron levels in serum and liver along with blood hemoglobin level than other ratios used here. Hence, it can be concluded that FVBH-1 (1:1) is an effective herbal formulation for the management of hypochlorhydria and related iron deficiency.

Protective effect of aqueous extract of seed of Psoralea corylifolia (Somraji) and seed of Trigonella foenum-graecum L. (Methi) in streptozotocin-induced diabetic rat: A comparative evaluation.

BACKGROUND: Psoralea corylifolia (Somraji) and Trigonella foenum-graecum L. (Methi), important medicinal plants widely used in India as folk medicine. Local people of West Bengal traditionally used the seeds of these plants to cure diabetes. OBJECTIVE: Present study was designed to investigate the antidiabetic efficacy of aqueous extract of seeds of these plants in separate or in composite manner in streptozotocin (STZ)-induced diabetic rat. MATERIALS AND METHODS: Diabetes was induced by intramuscular injection of STZ at the dose of 40 mg/ml of citrate buffer/kg body weight. Fasting blood glucose (FBG), glyclated hemoglobin (HbA1C) and activities of hexokinase, glucose-6-phosphate dehydrogenase and glucose-6-phosphatase of liver in experimental animals were assessed. Hyperlipidemic state developed in the experimental diabetic rat was assessed by measuring the levels of total cholesterol, triglyceride, and lipoproteins in serum. RESULTS: There was significant increased in the levels of FBG, HbA1C and lipid profiles along with diminution (P < 0.001) in the activities of hepatic hexokinase, glucose-6-phosphate dehydrogenase and elevation in glucose-6-phosphatase in diabetic control animals in respect to the untreated control. Significant recovery (P < 0.05) in the activities of above mentioned enzymes along with the correction in the levels of FBG, HbA1C and serum lipid profiles were noted towards the control level after the treatment of composite extract (i.e. 100 mg of Somraji: 100 mg of Methi, total 200 mg/kg body weight) than the individual extract (i.e. 200 mg of Somraji or 200 mg of Methi, per kg body weight) treatment. CONCLUSION: Results suggest that composite extract of above plant parts has more potent antidiabetic efficacy than the individual extract.

Overweight and obesity among early adolescent school girls in urban area of west bengal, India: prevalence assessment using different reference standards.

BACKGROUND: Overweight and obesity are epidemic and a 'public health crisis' among adolescents worldwide. The rising trends in adolescent obesity in girl are poorly documented in India. The aim of this study was to compare and assess the extent of overweight and obesity in early adolescent school girls using three references [World Health Organization (WHO) 2007; the Center for Diseases Control (CDC) 2000 and the International Obesity Task Force (IOTF) 2000]. METHODS: A cross sectional study was designed in 1375 early adolescent girl (10-14 years), in five Government affiliated schools of Kharagpur Municipality of West Bengal, India. RESULTS: Results of this study are eloquent of the fact that the roots of obesity lies in early stage of adolescence. Incidence of overweight, including obesity of participants was 10.62%, 7.64% and 7.49% depending on the references used (WHO, CDC and IOTF) respectively. Both incidence and remission rates were higher among younger girls. CONCLUSIONS: Regarding the harmful ramifications of overweight and obesity, it is encourage to healthy eating patterns and increase physical activity among early adolescent girls.

Antihyperglycemic and antihyperlipidemic effects of n-hexane fraction from the hydro-methanolic extract of sepals of Salmalia malabarica in streptozotocin-induced diabetic rats.

Bio-efficacy of n-hexane fraction of sepal of Salmalia malabarica was evaluated covering the biochemical sensors for the management of hyperglycemic and hyperlipidemic effects. Evaluation of n-hexane fraction of Salmalia malabarica (SMH) from hydro-methanolic (2:3) extract at the dose of 0.1 gm/kg body weight twice a day were investigated in normal and streptozotocin (STZ) induced diabetic rats. Normal and STZ-induced diabetic rats were divided into five groups. The effect of the fraction on fasting blood glucose (FBG), serum insulin, hemoglobin, glycated hemoglobin, total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDLc), low density lipoprotein cholesterol (LDLc), very low density lipoprotein cholesterol (VLDLc), phospholipids, free fatty acids, urea, uric acid, creatinine, albumin and transaminases were investigated in STZ-induced diabetic rat. A significant reduction of FBG level was observed after SMH treatment in STZ-induced diabetic rat. Treatment of diabetic rats with n-hexane fraction of this plant restored the levels of the above biochemical sensors significantly (p<0.001) in respect to the control. Histological studies of pancreas showed a qualitative diminution in the area of the islet's of Langerhans in diabetic group which was recovered by said fraction. Phytochemical screening of the fraction revealed the presence of flavonoids, terpenoids and steroids.

Effect of different solvent extracts of Benincasa hispida T. on experimental hypochlorhydria in rat.

Hypochlorhydria is a common problem in any age of people like other gastric disorders. It has so many etiologies such as sympathetic dominance, antiseretory drug use, excess sugar and refined foods, etc. In the present study, our objective was to search out the effective solvent extract of fruit of Benincasa hispida T. for the management of hypochlorhydria in model male albino rats. Hypochlorhydria was induced in rat as per standard method by oral administration of ranitidine. Different solvent extracts (Hydro-methanol, ethyl acetate, and aqueous) of ripe fruit of B. hispida were prepared following the standard protocol. Various parameters in this concern like free acidity, total acidity, pH, pepsin concentration, chloride and vitamin C levels in gastric juice were measured by standard biochemical and titrimetric methods. It was found that pre-administration followed by co-administration of aqueous extract of B. hispida (ABH) resulted significant correction of ranitidine-induced hypochlorhydria in rat. This aqueous extract-treated group showed increased levels of vitamin C, pepsin, and chloride concentration in gastric juice as well as the antioxidant status significantly (P<0.05) in respect to other extract-treated groups. From the results, it can be concluded that the ABH has most effective anti-hypochlorhydric and antioxidative efficacy than other solvent extracts of said plant fruit.

Antihyperglycemic and antioxidative effects of the hydro-methanolic extract of the seeds of Caesalpinia bonduc on streptozotocin-induced diabetes in male albino rats.

BACKGROUND: No satisfactory effective treatment is available yet to cure diabetes mellitus. Though, synthetic drugs are used but there are several drawbacks. The attributed antihyperglycemic effects of many traditional plants are due to their ability for the management of diabetes mellitus. MATERIALS AND METHODS: A hydromethanolic extract was administered orally at a dose of 250 mg/kg of body weight per day for 21 days. Its effects on the fasting blood glucose (FBG) level, activities of key carbohydrate metabolic enzymes like hexokinase, glucose-6-phosphatase, and glucose-6-phosphate dehydrogenase, and antioxidant enzymes like catalase and superoxide dismutase along with the effect on the lipid peroxidation level in hepatic tissues were measured. Glycogen levels were also assessed in hepatic and skeletal muscles and some toxicity parameters, such as serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, and alkaline phosphates activities were measured. RESULTS: Treatment of the hydromethanolic extract of the seeds of Caesalpinia bonduc resulted in a significant (P < 0.05) recovery in the activities of carbohydrate metabolic enzymes along with correction in FBG and glycogen levels as compared with the untreated diabetic group. The extract also resulted in a significant (P < 0.05) recovery in the activities of toxicity assessment enzyme parameters. Activities of antioxidant enzymes like catalase and superoxide dismutase along with the lipid peroxidation levels were also recovered significantly (P < 0.05) after the treatment of the extract. The corrective effects produced by the extract were compared with the standard antidiabetic drug, glibenclamide. CONCLUSION: Our findings provide that the extract shows possible antihyperglycemic and antioxidative activities.

Inhibitory effect of hydro-methanolic extract of seed of Holarrhena antidysenterica on alpha-glucosidase activity and postprandial blood glucose level in normoglycemic rat.

ETHNOPHARMACOLOGICAL RELEVANCE: The present experiment was conducted to search out the effect of hydro-methanolic extract of seed of Holarrhena antidysenterica on intestinal α-glucosidase activity in dose dependent manner and on the management of postprandial hyperglycemia in starch loaded rats. MATERIALS AND METHODS: Activity of intestinal α-glucosidase was measured by in vitro method. Fasting blood glucose level was determined by single touch glucometer. Total phenol and flavonoids of seed extract of Holarrhena antidysenterica were estimated using gallic acid and quercetin standard curves, respectively. RESULTS: The degree of elevation in blood glucose level after starch administration was significantly (p<0.05) less by the extract in respect to the control. The said extract also inhibited α-glucosidase activity having an IC(50) of 0.52mg/ml. Phytochemical study revealed that the extract is rich in phenolic compounds (60.23mg of gallic acid equivalent/g of extract) and flavonoids (360.23mg of quercetin equivalent/g of the extract). CONCLUSION: The extract exerts its antihyperglycemic effect by retarding the carbohydrate absorption from intestine through the inhibition in α-glucosidase activity and therefore resists postprandial hyperglycemia.

Antidiabetic Potentiality of the Aqueous-Methanolic Extract of Seed of Swietenia mahagoni (L.) Jacq. in Streptozotocin-Induced Diabetic Male Albino Rat: A Correlative and Evidence-Based Approach with Antioxidative and Antihyperlipidemic Activities.

Antidiabetic, antioxidative, and antihyperlipidemic activities of aqueous-methanolic (2 : 3) extract of Swietenia mahagoni (L.) Jacq. (family Meliaceae) seed studied in streptozotocin-induced diabetic rats. Feeding with seed extract (25 mg 0.25 mL distilled water(-1)100 gm b.w.(-1)rat(-1) day(-1)) for 21 days to diabetic rat lowered the blood glucose level as well as the glycogen level in liver. Moreover, activities of antioxidant enzymes like catalase, peroxidase, and levels of the products of free radicals like conjugated diene and thiobarbituric acid reactive substances in liver, kidney, and skeletal muscles were corrected towards the control after this extract treatment in this model. Furthermore, the seed extract corrected the levels of serum urea, uric acid, creatinine, cholesterol, triglyceride, and lipoproteins towards the control level in this experimental diabetic model. The results indicated the potentiality of the extract of S. mahagoni seed for the correction of diabetes and its related complications like oxidative stress and hyperlipidemia. The extract may be a good candidate for developing a safety, tolerable, and promising neutraceutical treatment for the management of diabetes.

Antioxidant potential of hydro-methanolic extract of seed of Caesalpinia bonduc: An in vitro study.

It is well known that the over production of reactive oxygen species is harmful for living organisms and it damages major cellular constituents such as DNA, protein, and lipid. At present, searching of new plant sources having free radical scavenging activity is an important field of research in phytomedicine as natural products are safe and relatively low cost. In this respect, attention has been focused to evaluate the antioxidant potential of hydro-methanolic extract of seed of Caesalpinia bonduc (Caesalpenacae) using different in vitro models. To evaluate the antioxidant activity, extract was examined on 2, 2-diphenyl-1-picrylhydrazyl radical scavenging effect, scavenging of hydrogen peroxide, hydroxyl radical scavenging potential, and anti-lipid peroxidation activity by biochemical methods. Total phenol and flavonoids contents in the said extract were measured biochemically as per standard methods. Results were compared with butylated hydroxyl toluene and α-tocopherol. Results indicated that hydro-methanolic extract has strong scavenging activity on 2, 2-diphenyl-1-picrylhydrazyl radical with IC(50) value 157.4 µg/ml, hydroxyl radical with IC(50) value 61.9 µg/ml and hydrogen peroxide with IC(50) value 64.32 µg/ml. Hydro-methanolic extract also showed notable inhibition in lipid peroxidation having IC(50) value 58.87 µg/ml. Phytochemical study focused that the extract is rich in phenolic compounds (24.66 mg gallic acid equivalent/g dried extract) and flavonoids (136.65 mg quercetin equivalent/g dried extract). Findings of the experiment indicated that the hydro-methanolic extract of seed of Caesalpinia bonduc is a source of natural antioxidants.

Comparative study on the spermicidal activity of organic solvent fractions from hydroethanolic extracts of Achyranthes aspera and Stephania hernandifolia in human and rat sperm.

BACKGROUND: This study was conducted to determine the most effective fraction of the hydroethanolic (water:ethanol, 1:1) extracts of Stephania hernandifolia leaves and Achyranthes aspera roots (in a composite manner at a ratio of 1:3, respectively) that will provide maximum spermicidal activity in human and rat spermatozoa out of five different ratios (1:1, 1:3, 1:7, 3:1 and 7:1) that have been studied in pilot experiments. STUDY DESIGN: n-Hexane, chloroform and ethyl acetate fractions of the hydroethanolic (1:1) extracts of S. hernandifolia and A. aspera were mixed at 1:3. Different concentrations were tested for sperm immobilization, sperm viability, acrosome status, 5'-nucleotidase activity and nuclear chromatin decondensation using human and rat spermatozoa for the selection of the most effective concentration. RESULTS: Out of three fractions of the hydroethanolic (1:1) extracts of the said plants, the n-hexane fraction was most effective, and the chloroform fraction exhibited minimum activity for this purpose. At a concentration of 0.1 g/mL hexane fraction, all sperm of the human sample were immobilized immediately (within 20 s). In case of the rat sample, all epididymal spermatozoa were immobilized immediately (within 20 s) by treatment with hexane fraction at a concentration of 0.004 g/mL. All human sperm were found to be nonviable within 20 min. The activity of acrosome enzymes was reduced, and significant release of 5'-nucleotidase (a plasma membrane marker) into the surrounding medium was noted after treatment with 0.1 g/mL hexane fraction, indicating that the hexane fraction affected the cytoarchitecture of the sperm plasma membrane. The maximum number of human sperm failed to decondense when treated with 0.1 g/mL hexane fraction, and sperm motility was also irreversible. The hexane fraction was tested in rats as vaginal contraceptive and showed 100% efficacy, indicating its potential for development as vaginal contraceptive. CONCLUSION: The findings indicate that, among the different fractions, the hexane fraction of the hydroethanolic extracts of the two plants produced the most effective spermicidal activity and can be considered as vaginal contraceptive.