Algae have long been exploited commercially and industrially as food, feed, additives, cosmetics, pharmaceuticals, and fertilizer, but now the trend is shifting towards the algae-mediated green synthesis of nanoparticles (NPs). This trend is increasing day by day, as algae are a rich source of secondary metabolites, easy to cultivate, have fast growth, and are scalable. In recent era, green synthesis of NPs has gained widespread attention as a safe, simple, sustainable, cost-effective, and eco-friendly protocol. The secondary metabolites from algae reduce, cap, and stabilize the metal precursors to form metal, metal oxide, or bimetallic NPs. The NPs synthesis could either be intracellular or extracellular depending on the location of NPs synthesis and reducing agents. Among the diverse range of algae, the most widely investigated algae for the biosynthesis of NPs documented are brown, red, blue-green, micro and macro green algae. Due to the biocompatibility, safety and unique physico-chemical properties of NPs, the algal biosynthesized NPs have also been studied for their biomedical applications, which include anti-bacterial, anti-fungal, anti-cancerous, anti-fouling, bioremediation, and biosensing activities. In this review, the rationale behind the algal-mediated biosynthesis of metallic, metallic oxide, and bimetallic NPs from various algae have been reviewed. Furthermore, an insight into the mechanism of biosynthesis of NPs from algae and their biomedical applications has been reviewed critically.

Melatonin, a multifunctional signaling molecule, is ubiquitously distributed in different parts of a plant and responsible for stimulating several physiochemical responses against adverse environmental conditions in various plant systems. Melatonin acts as an indoleamine neurotransmitter and is primarily considered as an antioxidant agent that can control reactive oxygen and nitrogen species in plants. Melatonin, being a signaling agent, induces several specific physiological responses in plants that might serve to enhance photosynthesis, growth, carbon fixation, rooting, seed germination and defense against several biotic and abiotic stressors. It also works as an important modulator of gene expression related to plant hormones such as in the metabolism of indole-3-acetic acid, cytokinin, ethylene, gibberellin and auxin carrier proteins. Additionally, the regulation of stress-specific genes and the activation of pathogenesis-related protein and antioxidant enzyme genes under stress conditions make it a more versatile molecule. Because of the diversity of action of melatonin, its role in plant growth, development, behavior and regulation of gene expression it is a plant’s master regulator. This review outlines the main functions of melatonin in the physiology, growth, development and regulation of higher plants. Its role as anti-stressor agent against various abiotic stressors, such as drought, salinity, temperatures, UV radiation and toxic chemicals, is also analyzed critically. Additionally, we have also identified many new aspects where melatonin may have possible roles in plants, for example, its function in improving the storage life and quality of fruits and vegetables, which can be useful in enhancing the environmentally friendly crop production and ensuring food safety.

Background & Objectives:Terrorist attack in Army Public School Peshawar, Pakistan left behind more than hundred children dead. It was the highest death toll of children in the world in a single terrorists attack. The attack dominated national and international news, high level security measures have been adopted in all school throughout Pakistan, which created fear and stress in children. The objective of the study was to determine post-traumatic stress disorder among children after six month of terrorist attack inspite of rigorous psychosocial support and rehabilitation.Methods:We wanted to determine Post Traumatic Stress Disorder (PTSD) among children of Army Public School of age range 10 to 18 years after 5 months of intervention and rehabilitation following terrorists attack. For this a self-report questionnaire, Child PTSD Symptom Scale (CPSS), which assess and identify symptoms matching DSM (Diagnostic and Statistical Manual of Mental Disorders) IV criteria for post-traumatic stress disorder of children, was filled. Informed consent was taken from school Principal and responders.Results:A total 205 students of age range 10 to 18 years participated in the study. The most frequent age group of the study were 16 years and 14 years students with frequency 58 (28.3%) and 46 (22.4%) respectively. Among 205 participated school children PTSD were found in 154 (75.2%) children while only 24.8% students had no PTSD symptoms. In more than 50% PTSD positive school children had functional impairment for each category of fun and hobbies, friendship, school work, family relation, doing chores, general happiness and saying prayers.Conclusion:Study found a very high prevalence of PTSD among 10 to 18 years age group students of Army Public School inspite of five months continuous intervention and rehabilitation services. Study showed that this age group needs long term psychosocial treatment in case of trauma.

Graphical demonstartion of the Manikara zapota-mediated biosynthesis of Bimetallic nanoparticles (BNPs) and evalution of their biological activities.

No abstract