Significance of Herbaspirillum sp. in biodegradation and biodetoxification of herbicides, pesticides, hydrocarbons and heavy metals - A review

In today's industrialized world, contamination of soil and water with various substances has emerged as a pressing concern. Bioremediation, with its advantages of degradation or detoxification, non-polluting nature, and cost-effectiveness, has become a promising method due to technological advancements. Among the bioremediation agents, bacteria have been highly explored and documented as a productive organism. Recently, few studies have reported on the significance of Herbaspirillum sp., a Gram-negative bacterium, in bioremediating herbicides, pesticides, polycyclic aromatic hydrocarbons, metalloids, and heavy metals, as well as its role in augmenting phytoremediation efforts. Herbaspirillum sp. GW103 leached 66% of Cu from ore materials and significantly enhanced the phytoaccumulation of Pb and Zn in plumule and radical tissues of Zea mays L. plants. Additionally, Herbaspirillum sp. WT00C reduced Se6+ into Se0, resulting in an increased Se0 content in tea plants. Also, Herbaspirillum sp. proved effective in degrading 0.6 mM of 4-chlorophenol, 92.8% of pyrene, 77.4% of fluoranthene, and 16.4% of trifluralin from aqueous solution and soil-water system. Considering these findings, this review underscores the need for further exploration into the pathways of pollutant degradation, the enzymes pivotal in the degradation or detoxification processes, the influence of abiotic factors and pollutants on crucial gene expression, and the potential toxicity of intermediate products generated during the degradation process. This perspective reframes the numerical data to underscore the underutilized potential of Herbaspirillum sp. within the broader context of addressing a significant research gap. This shift in emphasis aligns more closely with the problem-necessity for solution-existing unexplored solution framework.

Detoxification of p-nitrophenol (PNP) using Enterococcus gallinarum JT-02 isolated from animal farm waste sludge

Enterococcus gallinarum (JT-02) isolated and identified from the animal farm waste sludge was found to be capable of biodegrading p-nitrophenol (PNP), an organic compound used to manufacture drugs, fungicides, insecticides, dyes, and to darken leather. The intention of this study was to optimize the biodegradation by finding the optimal conditions for the specific strain through single-factor experiments. The bacterial strain was grown in Luria Bertani broth and various parameters were optimized to achieve the prime settings for the p-nitrophenol (PNP) biodegradation. The results indicated that the best setups for the biodegradation by the strain JT-02 was 100 mg/L of PNP; pH 7; 30 °C; 150 rpm in a shaker incubator and 3% (v/v) of inoculum dose. Once the optimal conditions were found, the bacteria were capable of degrading p-nitrophenol (98.21%) in 4 days. Intermediates produced during PNP biodegradation were identified using High Performance Liquid Chromatography (HPLC) analysis and the biodegradation pathway was elucidated. Phytotoxicity studies were carried out with Vigna radiata seeds to confirm the applicability and efficiency of PNP biodegradation.

A hybrid technique for sulfamethoxazole (SFM) removal using Enterobacter hormaechei HaG-7: Bio-electrokinetic degradation, pathway and toxicity

Prolonged exposure to antibiotics would likely favor the development of antibiotic resistance and their gene transfer among bacterial communities that are responsible for enriched antibiotic resistant microbes. Sulfamethoxazole (SFM) is a commonly used antibiotic that is released into the environment through human and animal wastes. Improper degradation of SFM poses severe threats to mankind and all life forms. The present study aims in analyzing the process and the probability of utilizing bio-electrokinetic degradation for elimination of SFM from artificially contaminated soil employing Enterobacter hormaechei HaG-7. The desired optimal conditions for SFM degradation (∼98%) were observed at SFM initial concentration (100 mg/L) with an inoculum dose (1% v/v) and applied potential voltage (1.5 V) at pH (7). The results indicated efficient and complete degradation of SFM when compared with the conventional biodegradation.

Enhanced visible light-driven photocatalysis of iron-oxide/titania composite: Norfloxacin degradation mechanism and toxicity study

A simulated visible light-mediated iron oxide-titania (IoT) nanocomposite was employed to degrade the antibiotic norfloxacin (NFN) photocatalytically. The photocatalyst were prepared using a sol-gel method with controlled titania loadings to iron oxide by altering the fabrications step. The nanocomposites were structurally characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), field emission high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Diffuse reflectance UV-visible spectra (DRS-UV) spectroscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy (XPS). It was observed that 100 mg/L of iron oxide doped titania loading at 1:4 (IoT-4) achieved the maximum photocatalytic activity in a 75 mg/100 mL of NFN solution within 60 min of the reaction time under visible light irradiation. The NFN degradation mechanism affirmed using HPLC-MS/MS analysis and the results confirmed the complete NFN degradation without residual intermediates. Significant, sustained recyclability was obtained by completely removing the contaminant up to 5 cycles with 90% degradation ability till nine cycles. Bacterial- and phytotoxicity data ascertain that the photocatalyzed and contaminant-free water is safe for the environment. The outstanding photocatalytic performance in removing organic pollutants indicates the potential application of IoT nanocomposites in real-time environmental remediation.

Enhanced visible light-driven photocatalytic activity of reduced graphene oxide/cadmium sulfide composite: Methylparaben degradation mechanism and toxicity

Reduced graphene oxide/cadmium sulfide (RGOCdS) nanocomposite synthesized through solvothermal process was used for methylparaben (MeP) degradation. The crystallinity of the nanocomposite was ascertained through X-ray diffraction. High resolution transmission electron microscope (HRTEM) results proved the absence of any free particle beyond the catalyst surface ensuring the composite nature of the prepared material. The enhancement in the activity on doping with RGO was substantiated by diffuse reflectance spectroscopy (DRS-UV). It is evident from the photocatalytic degradation experiments that RGOCdS is more efficient than pure CdS. Maximum MeP degradation (100%) was achieved after 90 min of irradiation with 750 mg/L RGOCdS dosage at an acidic pH of 3, for an initial MeP concentration of 30 mg/L. The degradation mechanism substantiated through HPLC-MS/MS analysis showed the complete degradation of MeP without any residual intermediaries. The catalyst could be sustained and reused for up to 9 cycles of usage. Phytotoxicity and mycotoxicity results evidently ascertain the environmental implications of the photocatalyst material.

Nomophobia: A Mixed-Methods Study on Prevalence, Associated Factors, and Perception among College Students in Puducherry, India

BACKGROUND

As more people are utilizing smartphones, nomophobia is also on the rise. Several Indian studies have revealed nomophobia among young adults. The severity of nomophobia and related behaviors is underrated and often go unnoticed in India.

METHODS

The sociodemographic characteristics, smartphone usage pattern, and perceived ill-health related to smartphone usage of the participants were obtained using a semistructured questionnaire. Twenty-item Nomophobia questionnaire was used to assess nomophobia. In-depth interviews were conducted among students with moderate and severe nomophobia scores.

RESULTS

Among the 774 participants, 23.5% had severe nomophobia scores. Older age, male gender, duration and frequency of smartphone usage, use for social networking, checking without reason, and checking smartphone after waking up in the morning were significantly associated with nomophobia. The in-depth interview showed attributes of addiction among the students, like dependency and compulsive behavior. Students also experienced anxiety and frustration when they had to part with their smartphones.

CONCLUSION

A sizable minority of the students had signs of severe nomophobia, distinct patterns of usage, and misperceptions regarding health and their usage pattern.

Clinical Tests Combined with Color Doppler Versus Color Doppler Alone in Identifying Incompetent Perforator Veins of the Lower Limb: A Prospective Analytical Study

Background The color Doppler, a better investigation to identify the perforators objectively has replaced the clinical examination for the same. However, this has led to a significant number of negative explorations and cosmetic disfigurement. Objective To compare the efficacy of the clinical tests combined with the color Doppler versus color Doppler alone to identify the perforator incompetence during the surgery for primary varicose veins of the lower limb. Methods This was a prospective analytical study, including 61 lower limb varicose vein patients who belonged to the Clinical-Etiology-Anatomy-Pathophysiology (CEAP) class four-six, planned for the surgical treatment for perforator incompetence, excluding those requiring additional vascular or nonvascular procedure, recurrent varicose veins and those who had injection sclerotherapy prior to the surgery. The clinical tests, including Trendelenburg's test, multiple tourniquet tests and, the Fegan's tests were performed and incompetent perforators were marked on a template as 'C' to indicate the clinically positive perforator incompetence. The patients were then examined with the color Doppler ultrasound and the pathological incompetent perforators were marked as 'D'. The surgical management of the perforator incompetence was done by stab ligation. The incision was made in the color Doppler 'D' marked sites as it has been the standard protocol. The number of incompetent perforators identified during the surgical exploration were categorized as 'D' positive or 'C' and 'D' positive and were recorded in the specified proforma. Results It was found that the mean number of the perforator incompetence identified by the color Doppler alone was 8.2 whereas during the surgery, only a mean of six perforators was identified, leading to 20 unnecessary explorations per 10 patients (8.2 vs. 6; mean difference 2.229; P <0.001). The mean number of the perforator incompetence identified by the color Doppler combined with the clinical tests was 4.5 and during the surgery, a mean of four perforators was identified (4.5 vs. 4; mean difference 0.377; P <0.001). The color Doppler combined with the clinical examination lead to only four unnecessary explorations per 10 patients. Conclusion A combination of both the clinical tests and the color Doppler ultrasound has a higher accuracy in detecting perforator incompetence and can reduce the number of negative explorations by the rate of 16 unnecessary explorations per 10 patients.

F wave index: A diagnostic tool for peripheral neuropathy

Background & objectives:

Each skeletal muscle is usually supplied by two or more nerve roots and if one nerve root is affected and the other is spared, the clinically used F wave minimum latency can still be normal. An F wave index was constructed taking into consideration the other parameters of the F wave such as persistence, chronodispersion, latency, arm-length to determine its usefulness in the diagnosis of peripheral neuropathy. This study was undertaken to construct the F wave index in the upper limb for the median nerve in normal healthy adult males and in patients with peripheral neuropathy and to compare the values obtained in both groups.

Methods:

This hospital-based study was carried out on 40 males who were diagnosed to have peripheral neuropathy and on 40 age matched healthy males who served as the control group. The F wave recording was done using a digitalized nerve conduction/electromyography/EP machine in a quiet and dimly lit room. All recordings were done between 0900 and 1100 h at an ambient temperature of 22°C. The F wave recording was obtained from a fully relaxed muscle by stimulating the median nerve.

Results:

The median value for F wave index obtained from median nerve (abductor pollicis brevis) in patients with peripheral neuropathy [right arm - 35.85, interquartile range (IQR) - 35.26; left arm - 39.49, IQR - 39.49] was significantly lower (P=0.001) as compared to the control group (right arm - 102.62, IQR - 83.76; left arm - 77.43, IQR - 58.02).

Interpretation & conclusions:

Our results showed that F wave index in upper limb was significantly lower in patients with peripheral neuropathy than the healthy controls, and could be used for early detection of peripheral neuropathy.

Unmet Needs of Family Planning Among Women: A Cross-Sectional Study in a Rural Area of Kanchipuram District, Tamil Nadu, South India

BACKGROUND

Global contraceptive usage was 63.3 % in 2010 which was 9 % more than that in 1990. NFHS-III 2005-2006 revealed that the contraceptive prevalence rate was 56 % while in the past decade it was 48 %. In India, female sterilization is the most commonly preferred method of contraception accounting for 76 %, while in Tamil Nadu it was 90 %. Thus, this study aims at measuring the prevalence of unmet needs of family planning and its determinants in a rural area of Kancheepuram district, Tamil Nadu.

MATERIALS AND METHODS

The study was carried out as a community-based cross-sectional study in Chunambed panchayat, a rural area in Kanchipuram District, Tamil Nadu, India, among 505 women of age group 15-49 years. Cluster random sampling was done to select the households to include in the study. In every household, all the available and eligible women were explained about the study and recruited after obtaining informed consent.

STATISTICAL ANALYSIS

Chi-square test was applied for finding the difference in proportion, and p value <0.05 was considered statistically significant.

RESULTS

The prevalence of unmet need for family planning in our study population was nearly 31 %; it was even more for younger age groups and for the women whose family size was less. 51.7 % of the participants were currently using a contraceptive measure and very few of their partners used contraception. Government health facilities were the major source of contraceptive service and majority of our participants were well aware about the various contraceptive methods.

CONCLUSION

Unmet needs of family planning were high in our study population, and the knowledge about the contraceptive use and family planning was found to be fairly adequate.

Determinants of Patient's Adherence to Hypertension Medications in a Rural Population of Kancheepuram District in Tamil Nadu, South India

Context:

Non-communicable diseases, no longer a disease of the rich, impose a great threat in the developing nations due to demographic and epidemiological transition. This increasing burden of non-communicable diseases and their risk factors is worrisome. Adherence to hypertension (HT) medication is very important for improving the quality of life and preventing complications of HT.

Aim:

To study the factors determining adherence to HT medication.

Settings and Design:

A community-based cross-sectional study was conducted in a rural area of Kancheepuram district, Tamil Nadu, with a total population of around 16,005.

Materials and Methods:

This study was carried out over a period of 6 months (February-July) using a pre-structured and validated questionnaire. All eligible participants were selected by house-to-house survey and individuals not available on three consecutive visits were excluded from the study. The questionnaire included information on demographic characteristics, lifestyle habits, adherence to HT medication, blood pressure, and body mass index (BMI). Caste was classified based on Tamil Nadu Public Service commission.

Statistical Analysis:

Data were entered in MS Excel and analyzed in SPSS version 16. P value <0.05 was considered statistically significant. Ethical Consideration: Informed verbal consent was obtained prior to data collection. The patient's adherence to HT medication was assessed using the Morisky 4-Item Self-Report Measure of Medication-taking Behavior [MMAS-4].

Results:

We studied 473 hypertensive patients of which 226 were males and 247 were females. The prevalence of adherence was 24.1% (n = 114) in the study population. Respondents with regular physical activity, non-smokers and non-alcoholics were more adherent to HT medication as compared with respondents with sedentary lifestyle, smoking and alcohol intake (P < 0.005). Based on health belief model, the respondents who perceived high susceptibility, severity, benefit had better adherence compared with moderate and low susceptibility, severity, benefit.

Knowledge and skills of primary health care workers trained on integrated management of neonatal and childhood illness: follow-up assessment 3 years after the training

BACKGROUND

The primary health care workers of a district in northern India were trained in the year 2006 for Integrated Management of Neonatal and Childhood Illness (IMNCI) using two different training methods: conventional 8-day training and new interrupted 5-day training. Knowledge and skills may decline over a period of time. Rate of decline may be associated with the type of training. A study was thus conducted to see the retention of knowledge and skills in the two training groups, 3 years after the initial training.

MATERIALS AND METHODS

This study was done in the Panchkula district of Haryana state in northern India. In the year 2006, 50 primary health care workers were given new interrupted 5-day training and another 35 workers were given conventional 8-day training on IMNCI. Knowledge and skills of the same workers were evaluated in the year 2009, using the same methodology and tools as were used in the year 2006. Data analysis was done to see the extent of decline in knowledge and skills in these 3 years and whether decline was more in any particular training group.

RESULTS

Compared to post-training score in the year 2006, composite knowledge and skill scores for Auxilliary Nurse Midwives (ANMs) and Anganwari workers (AWWs) together declined significantly in the year 2009 from 74.6 to 58.0 in 8-day training group and from 73.2 to 57.0 in 5-day training group (P < 0.001). Follow-up composite scores in the two training groups were similar. Whereas the decline was more for knowledge scores in 8-day training group and for skill score in 5-day training group, the pattern of decline was inconsistent for different health conditions and among ANMs and AWWs.

CONCLUSION

Long-term retention of knowledge and skills in 5-day group was equivalent to that in 8-day training group. Refresher trainings may boost up the decline in the knowledge and skills.