Plants are vulnerable to a number of abiotic and biotic stresses that cause a substantial decrease in the production of plants. Plants respond to different environmental stresses by experiencing a ...series of molecular and physiological changes coordinated by various phytohormones. The use of phytohormones to alleviate stresses has recently achieved increasing interest. Brassinosteroids (BRs) are a group of polyhydroxylated steroidal phytohormones that are required for the development, growth, and productivity of plants. These hormones are involved in regulating the division, elongation, and differentiation of numerous cell types throughout the entire plant life cycle. BR studies have drawn the interest of plant scientists over the last few decades due to their flexible ability to mitigate different environmental stresses. BRs have been shown in numerous studies to have a positive impact on plant responses to various biotic and abiotic stresses. BR receptors detect the BR at the cell surface, triggering a series of phosphorylation events that activate the central transcription factor (TF) Brassinazole-resistant 1 (BZR1), which regulates the transcription of BR-responsive genes in the nucleus. This review discusses the discovery, occurrence, and chemical structure of BRs in plants. Furthermore, their role in the growth and development of plants, and against various stresses, is discussed. Finally, BR signaling in plants is discussed.
Bacillus volatiles to control plant nematodes is a topic of great interest among researchers due to its safe and environmentally friendly nature. Bacillus strain GBSC56 isolated from the Tibet region ...of China showed high nematicidal activity against M. incognita, with 90% mortality as compared with control in a partition plate experiment. Pure volatiles produced by GBSC56 were identified through gas chromatography and mass spectrometry (GC-MS). Among 10 volatile organic compounds (VOCs), 3 volatiles, i.e., dimethyl disulfide (DMDS), methyl isovalerate (MIV), and 2-undecanone (2-UD) showed strong nematicidal activity with a mortality rate of 87%, 83%, and 80%, respectively, against M. incognita. The VOCs induced severe oxidative stress in nematodes, which caused rapid death. Moreover, in the presence of volatiles, the activity of antioxidant enzymes, i.e., SOD, CAT, POD, and APX, was observed to be enhanced in M. incognita-infested roots, which might reduce the adverse effect of oxidative stress-induced after infection. Moreover, genes responsible for plant growth promotion SlCKX1, SlIAA1, and Exp18 showed an upsurge in expression, while AC01 was downregulated in infested plants. Furthermore, the defense-related genes (PR1, PR5, and SlLOX1) in infested tomato plants were upregulated after treatment with MIV and 2-UD. These findings suggest that GBSC56 possesses excellent biocontrol potential against M. incognita. Furthermore, the study provides new insight into the mechanism by which GBSC56 nematicidal volatiles regulate antioxidant enzymes, the key genes involved in plant growth promotion, and the defense mechanism M. incognita-infested tomato plants use to efficiently manage root-knot disease.
Microbial Proteases Applications Razzaq, Abdul; Shamsi, Sadia; Ali, Arfan ...
Frontiers in bioengineering and biotechnology,
06/2019, Letnik:
7
Journal Article
Recenzirano
Odprti dostop
The use of chemicals around the globe in different industries has increased tremendously, affecting the health of people. The modern world intends to replace these noxious chemicals with ...environmental friendly products for the betterment of life on the planet. Establishing enzymatic processes in spite of chemical processes has been a prime objective of scientists. Various enzymes, specifically microbial proteases, are the most essentially used in different corporate sectors, such as textile, detergent, leather, feed, waste, and others. Proteases with respect to physiological and commercial roles hold a pivotal position. As they are performing synthetic and degradative functions, proteases are found ubiquitously, such as in plants, animals, and microbes. Among different producers of proteases,
sp. are mostly commercially exploited microbes for proteases. Proteases are successfully considered as an alternative to chemicals and an eco-friendly indicator for nature or the surroundings. The evolutionary relationship among acidic, neutral, and alkaline proteases has been analyzed based on their protein sequences, but there remains a lack of information that regulates the diversity in their specificity. Researchers are looking for microbial proteases as they can tolerate harsh conditions, ways to prevent autoproteolytic activity, stability in optimum pH, and substrate specificity. The current review focuses on the comparison among different proteases and the current problems faced during production and application at the industrial level. Deciphering these issues would enable us to promote microbial proteases economically and commercially around the world.
Biofilms are known to pose great risks in clinical settings, drinking water systems, and food industries as they show considerable resistance to various environmental stresses. This study ...investigates the antibiofilm potential of different essential oils against the test organisms Staphylococcus aureus (ATCC 25923) and Klebsiella pneumoniae (ATCC 13883). Moreover, different stages of biofilm formation were also assessed using light microscopic assays. For determining the antibiofilm activity, a total of five essential oils namely cinnamon (Cinnamomum Verum), tea tree (Melaleuca alternifolia), lavender (Lavandula), peppermint (Mentha piperita), and lemongrass (Cymbopogon citratus) were tested for their ability to inhibit the initial attachment of microbial cells as well as the eradication of mature biofilm using the microtitre plate assay. For both the test strains (S. aureus and K. pneumoniae) the concentration of 30 μl/100 μl of cinnamon oil exhibited the highest antibiofilm activity followed by the activity of peppermint oil at the same concentration. These results were further validated by employing the light microscopy assay for observing the antibiofilm potential of cinnamon and peppermint essential oils.
Microscopic examination of antibiofilm activity of essential oils
Endophytic bacterial communities are beneficial communities for host plants that exist inside the surfaces of plant tissues, and their application improves plant growth. They benefit directly from ...the host plant by enhancing the nutrient amount of the plant’s intake and influencing the phytohormones, which are responsible for growth promotion and stress. Endophytic bacteria play an important role in plant-growth promotion (PGP) by regulating the indirect mechanism targeting pest and pathogens through hydrolytic enzymes, antibiotics, biocontrol potential, and nutrient restriction for pathogens. To attain these benefits, firstly bacterial communities must be colonized by plant tissues. The nature of colonization can be achieved by using a set of traits, including attachment behavior and motility speed, degradation of plant polymers, and plant defense evasion. The diversity of bacterial endophytes colonization depends on various factors, such as plants’ relationship with environmental factors. Generally, each endophytic bacteria has a wide host range, and they are used as bio-inoculants in the form of synthetic applications for sustainable agriculture systems and to protect the environment from chemical hazards. This review discusses and explores the taxonomic distribution of endophytic bacteria associated with different genotypes of rice plants and their origin, movement, and mechanism of PGP. In addition, this review accentuates compressive meta data of endophytic bacteria communities associated with different genotypes of rice plants, retrieves their plant-growth-promoting properties and their antagonism against plant pathogens, and discusses the indication of endophytic bacterial flora in rice plant tissues using various methods. The future direction deepens the study of novel endophytic bacterial communities and their identification from rice plants through innovative techniques and their application for sustainable agriculture systems.
Cucumber is an important vegetable but highly sensitive to salt stress. The present study was designed to investigate the comparative performance of cucumber genotypes under salt stress (50 mmol L
) ...and stress alleviation through an optimized level of triacontanol @ 0.8 mg L
. Four cucumber genotypes were subjected to foliar application of triacontanol under stress. Different physiological, biochemical, water relations and ionic traits were observed to determine the role of triacontanol in salt stress alleviation. Triacontanol ameliorated the lethal impact of salt stress in all genotypes, but Green long and Marketmore were more responsive than Summer green and 20252 in almost all the attributes that define the genetic potential of genotypes. Triacontanol performs as a good scavenger of ROS by accelerating the activity of antioxidant enzymes (SOD, POD, CAT) and compatible solutes (proline, glycinebetaine, phenolic contents), which lead to improved gas exchange attributes and water relations and in that way enhance the calcium and potassium contents or decline the sodium and chloride contents in cucumber leaves. Furthermore, triacontanol feeding also shows the answer to yield traits of cucumber. It was concluded from the results that the salinity tolerance efficacy of triacontanol is valid in enhancing the productivity of cucumber plants under salt stress. Triacontanol was more pronounced in green long and marketer green than in summer green and 20252. Hence, the findings of this study pave the way towards the usage of triacontanol @ 0.8 mg L
, and green long and marketer genotypes may be recommended for saline soil.
Urinary tract infection is an infectious disease that requires immediate treatment. It can occur in any age group and involves both genders equally. The present study was to check the resistance of ...some antibiotics and to assess the antibacterial potential of three extracts of three plants against notorious bacteria involved in urinary tract infections. Along with assessing the antibacterial activity of plant extracts, we checked for the anticancer potential of these extracts against the cancer cell lines MCF-7 and A2780. Cancer is the leading cause of mortality in developed countries. Determinations of total flavonoid content, total phenolic content, total alkaloid content, total tannin content, total carotenoid content, and total steroid content were performed. The disk diffusion method was used to analyze the antibacterial activity of plant extracts. Ethanolic extract of
showed sensitivity (25-28 mm) against bacteria, whereas chloroform and hexane extracts showed resistance against all bacteria except
(25 mm). Ethanolic extract of
L. showed sensitivity (22-25 mm) against bacteria, whereas chloroform and hexane extracts showed resistance. Ethanolic extract of
L. showed sensitivity (8-16 mm) against all bacteria except
, whereas chloroform and hexane extracts showed resistance. Positive controls showed variable zones of inhibition (2-60 mm), and negative control showed 0-1 mm. The antibiotic resistance was much more prominent in the case of hexane and chloroform extracts of all plants, whereas ethanolic extract showed a sensitivity of bacteria against extracts. Both cell lines, MCF-7 and A2780, displayed decreased live cells when treated with plant extracts.
The doubled haploid (DH) technology is employed worldwide in various crop-breeding programs, especially maize. Still, restoring tassel fertility is measured as one of the major restrictive factors in ...producing DH lines. Colchicine, nitrous oxide, oryzalin, and amiprophosmethyl are common chromosome-doubling agents that aid in developing viable diploids (2n) from sterile haploids (n). Although colchicine is the most widely used polyploidy-inducing agent, it is highly toxic to mammals and plants. Therefore, there is a dire need to explore natural, non-toxic, or low-toxic cheaper and accessible substitutes with a higher survival and fertility rate. To the best of our knowledge, the advanced usage of human anticancer drugs “Paclitaxel (PTX)” and “Caffeine–Taurine (CAF–T)” for in vivo maize haploids doubling is being disclosed for the first time. These two antimitotic and antimicrotubular agents (PTX and CAF–T) were assessed under various treatment conditions compared to colchicine. As a result, the maximum actual doubling rates (ADR) for PTX versus colchicine in maize haploid seedlings were 42.1% (400 M, 16 h treatment) versus 31.9% (0.5 mM, 24 h treatment), respectively. In addition, the ADR in maize haploid seeds were CAF–T 20.0% (caffeine 2 g/L + taurine 12 g/L, 16 h), PTX 19.9% (100 μM, 24 h treatment), and colchicine 26.0% (2.0 mM, 8 h treatment). Moreover, the morphological and physiological by-effects in haploid plants by PTX were significantly lower than colchicine. Hence, PTX and CAF–T are better alternatives than the widely used traditional colchicine to improve chromosome-doubling in maize crop.
is a destructive fungal pathogen that threatens the production and quality of wheat, and controlling this pathogen is a significant challenge. As the cost-effective homolog of melatonin, ...5-methoxyindole showed strong activity against
In the present study, our results showed the strong adverse activity of 5-methoxyindole against
by inhibiting its growth, formation, and conidia germination. In addition, 5-methoxyindole could induce malformation, reactive oxygen species (ROS) accumulation, and cell death in
hyphae and conidia. In response to 5-methoxyindole,
genes involved in scavenging reactive oxygen species were significantly downregulated. Overall, these findings reveal the mechanism of antifungal action of melatonin-homolog 5-methoxyindole. To the best of our knowledge, this is the first report that a novel melatonin homolog confers strong antifungal activity against
, and 5-methoxyindole is a potential compound for protecting wheat plants from
infection.
Copper (Cu) is an abundant essential micronutrient element in various rocks and minerals and is required for a variety of metabolic processes in both prokaryotes and eukaryotes. However, excess Cu ...can disturb normal development by adversely affecting biochemical reactions and physiological processes in plants. The present study was conducted to explore the potential of gibberellic acid (GA
3
) on fibrous jute (
Corchorus capsularis
L.) seedlings grown on Cu mining soil obtained from Hubei Province China. Exogenous application of GA
3
(10, 50, and 100 mg/L) on 60-day-old seedlings of
C. capsularis
which was able to grow in highly Cu-contaminated soil (2221 mg/kg) to study different morphological, physiological, and Cu uptake and accumulation in different parts of
C. capsularis
seedlings. According to the results, increasing concentration of GA
3
(more likely 100 mg/L) alleviates Cu toxicity in
C. capsularis
seedlings by increasing plant growth, biomass, photosynthetic pigments, and gaseous exchange attributes. The results also showed that exogenous application of GA
3
reduced oxidative stress in
C. capsularis
seedlings by the generation of extra reactive oxygen species (ROS). The reduction in oxidative stress in
C. capsularis
seedlings is because that plant has strong enzymatic antioxidants superoxidase dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), and catalase (CAT), which ultimately increased their activities to overcome oxidative damage in the cells/tissues. In addition to the plant growth, biomass, and photosynthesis, foliar application of GA
3
also helps to increase metal (Cu) concentration in different parts of the plants when compared to 0 mg/L of application of GA
3
. From these findings, we can conclude that foliar application of GA
3
plays a promising role in reducing ROS generation in the plant cells/tissues and increased phytoextraction of Cu in different plant parts. However, more investigation is needed on field experiments to find a combination of GA
3
with a very higher concentration of Cu using fibrous
C. capsularis
.
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