ESPÉCIES BOTÂNICAS EXÓTICAS PRESENTES EM PARNAÍBA-PI

Introdução: Parnaíba encontra-se no extremo norte piauiense, na Faixa Litorânea e na Zona da Mata, uma área de transição entre Cerrado e Caatinga, sob influência Amazônica e do Oceano Atlântico. O município tem 436.907 km2 e população estimada em 153.863 habitantes. Estão presentes várias fitofisionomias: praias, dunas, restingas, tabuleiros litorâneos, brejos e manguezais, associados a uma rica biodiversidade. Apesar disso, é comum encontrar árvores e palmeiras exóticas na composição urbana, muitas das quais apresentam boas adaptabilidade e alta capacidade de multiplicação, o que as torna potencialmente invasoras. Objetivos: Identificar arbustos, árvores e palmeiras exóticas em Parnaíba-PI. Material e métodos: Visitas de campo em amostras das fitofisionomias presentes, e nas principais avenidas da zona urbana, de março a setembro de 2021, associadas a estudo bibliográfico. Resultados: As espécies identificadas foram Nim (Azadirachta indica), Algaroba (Prosopis juliflora), Tamarindeiro (Tamarindus indica), Mangueira (Magnifera indica), Jamelão (Syzygium cumini), Moringa (Moringa oleifera), Casuarina (Casuarina equisetifolia), Casatanhola (Terminalia catappa), Tamareira (Phoenix dactylifera), Palmeira Imperial (Roystonea oleracea), Leucena (Leucaena leucocephala), Eucalipto (Eucalyptus sp.), Jambo-vermelho (Syzygium malaccensis), Coqueiro (Cocos nucifera), Chichá-fedorento (Sterculia foetida), Baobá (Adansonia digitata), Flamboyant (Delonix regia), Mamona (Ricinus communis), Algodão-de-seda (Calotropis procera) e Jaqueira (Artocapus heterophyllus). Conclusão: A substituição de plantas nativas por exóticas, além de uniformizar as paisagens e provocar alterações ecológicas e culturais, é uma das causas da perda de biodiversidade no mundo. O Nim possui azadiractina em seu pólen, tóxico para as abelhas, o que pode provocar alterações populacionais desses polinizadores e prejudicar a manutenção do ecossistema e produção agrícola. Assim como outras plantas exóticas, o Nim possui frutos atrativos para a fauna, o que faz com que seja disperso rapidamente, tornando-se invasor. Deve-se evitar o uso de plantas exóticas e focar no uso de plantas nativas, prezando pela variedade biológica e genética, para maximizar os serviços ecossistêmicos e a sucessão ecológica, além de criar memória afetiva com a população e um banco urbano de sementes nativas.

Effect of UV Irradiation (A and C) on Casuarina equisetifolia-Mediated Biosynthesis and Characterization of Antimicrobial and Anticancer Activity of Biocompatible Zinc Oxide Nanoparticles

The green synthesis of nanoparticles has emerged as a simple, safe, sustainable, reliable and eco-friendly protocol. Among different types of NPs, green-synthesized zinc oxide NPs (ZnONPs) show various promising biological uses due to their interesting magnetic, electrical, optical and chemical characteristics. Keeping in view the dependence of the therapeutic efficacy of NPs on their physico-chemical characteristics, the green synthesis of ZnONPs using Casuarina equisetifolia leaf extract under UV-A and UV-C light was carried out in this study. UV-irradiation helped to control the size and morphology of ZnONPs by exciting the electrons in the photoactive compounds of plant extracts to enhance the bio-reduction of ZnO into ZnONPs. C. equisetifolia leaf extract was found enriched with phenolic (2.47 ± 0.12 mg GAE/g DW) and flavonoid content (0.88 ± 0.28 mg QE/g DW) contributing to its 74.33% free-radical scavenging activity. FTIR spectra showed the involvement of polyphenols in the bio-reduction, stabilization and capping of ZnONPs. Moreover, SEM-EDX and XRD analyses showed great potential of UV-C light in yielding smaller (34–39 nm) oval-shaped ZnONPs, whereas UV-A irradiation resulted in the formation of fairly spherical 67–71 nm ZnONPs and control ZnONPs were of mixed shape and even larger size (84–89 nm). Green-synthesized ZnONPs, notably CE-UV-C-ZnONPs, showed promising anti-bacterial activities against Bacillus subtilis, Pseudomonas fluorescens and Pseudomonas aeruginosa. Moreover, ZnONPs also enhanced ROS production which led to a significant loss of mitochondrial membrane potential and activated caspase-3 gene expression and caspase-3/7 activity in human hepatocellular carcinoma (HepG2) cells. CE-UV-C-ZnONP treatment reduced HepG2 cell viability to as low as 36.97% owing to their unique shape and smaller size. Lastly, ZnONPs were found to be highly biocompatible towards brine shrimp and human red blood cells suggesting their bio-safe nature. This research study sheds light on the plausible role of UV radiation in the green synthesis of ZnONPs with reasonable control over their size and morphology, thus improving their biological efficacy.

Transcriptome and structure analysis in root of Casuarina equisetifolia under NaCl treatment

Background High soil salinity seriously affects plant growth and development. Excessive salt ions mainly cause damage by inducing osmotic stress, ion toxicity, and oxidation stress. Casuarina equisetifolia is a highly salt-tolerant plant, commonly grown as wind belts in coastal areas with sandy soils. However, little is known about its physiology and the molecular mechanism of its response to salt stress. Results Eight-week-old C. equisetifolia seedlings grown from rooted cuttings were exposed to salt stress for varying durations (0, 1, 6, 24, and 168 h under 200 mM NaCl) and their ion contents, cellular structure, and transcriptomes were analyzed. Potassium concentration decreased slowly between 1 h and 24 h after initiation of salt treatment, while the content of potassium was significantly lower after 168 h of salt treatment. Root epidermal cells were shed and a more compact layer of cells formed as the treatment duration increased. Salt stress led to deformation of cells and damage to mitochondria in the epidermis and endodermis, whereas stele cells suffered less damage. Transcriptome analysis identified 10,378 differentially expressed genes (DEGs), with more genes showing differential expression after 24 h and 168 h of exposure than after shorter durations of exposure to salinity. Signal transduction and ion transport genes such as HKT and CHX were enriched among DEGs in the early stages (1 h or 6 h) of salt stress, while expression of genes involved in programmed cell death was significantly upregulated at 168 h, corresponding to changes in ion contents and cell structure of roots. Oxidative stress and detoxification genes were also expressed differentially and were enriched among DEGs at different stages. Conclusions These results not only elucidate the mechanism and the molecular pathway governing salt tolerance, but also serve as a basis for identifying gene function related to salt stress in C. equisetifolia.

Pharmacognostic, Phytochemical, Physico-chemical Standardization of Casuarina equisetifolia Stem-Inner bark

Over three thousand years in India, the Ayurvedic system of medicine has been in use. The phytomedicine, which is modernized method of formulating different kinds of herbal medicines, has yielded a new herbal product as well as new system of herbal medicine. The plant Casuarina equisetifolia is evergreen tree; belongs to family Casuarinaceae generally, attain height up to 50 m, introduced into India. The presence of different chemical constituents responsible for pharmacological activity such as analgesic, anti-inflammatory, Anti-histaminic, Wound healing. This research article highlighted Pharmacognostic account as well as physico-chemical evaluation, which shows how it will effective in the treatment of disease and disorder using herbal medicine. In addition to that, the Stem-inner bark of Casuarina equisetifolia is phytochemically evaluated using three different extract of Casuarina equisetifolia such as Methanol, Ethanol and Aqueous extract to show which secondary metabolites are present and result is that Methanol extract shows maximum Phenol, Tannin, flavonoid and Terpenoid content followed by Ethanol extract and then aqueous extract so that one can conclude stem-inner bark of Casuarina equisetifolia responsible for different pharmacological activity.

Genome-wide analysis of MYB transcription factors and their responses to salt stress in Casuarina equisetifolia

Background MYB transcription factors are a kind of DNA binding protein that can specifically interact with the promoter region. Members of MYB TFs are widely involved in plant growth and development, secondary metabolism, stress response, and hormone signal transduction. However, there is no report of comprehensive bioinformatics analysis on the MYB family of Casuarina equisetifolia. Results In this study, bioinformatics methods were used to screen out 182 MYB transcription factors from the Casuarina equisetifolia genome database, including 69 1R-MYB, 107 R2R3-MYB, 4 R1R2R3-MYB, and 2 4R-MYB. The C. equisetifolia R2R3-MYB genes were divided into 29 groups based on the phylogenetic topology and the classification of the MYB superfamily in Arabidopsis thaliana, while the remaining MYB genes (1R-MYB, R1R2R3-MYB, and 4R-MYB) was divided into 19 groups. Moreover, the conserved motif and gene structure analysis shown that the members of the CeqMYBs were divided into the same subgroups with mostly similar gene structures. In addition, many conserved amino acids in the R2 and R3 domains of CeqMYBs by WebLogo analysis, especially tryptophan residues (W), with 3 conserved W in R2 repeat and 2 conserved W in R3 repeat. Combining promoter and GO annotation analysis, speculated on the various biological functions of CeqMYBs, thus 32 MYB genes were selected to further explore its response to salt stress by using qPCR analysis technique. Most CeqMYB genes were differentially regulated following multiple salt treatments. Conclusions Seven genes (CeqMYB164, CeqMYB4, CeqMYB53, CeqMYB32, CeqMYB114, CeqMYB71 and CeqMYB177) were assigned to the “response to salt stress” by GO annotation. Among them, the expression level of CeqMYB4 was up-regulated under various salt treatments, indicating CeqMYB4 might participated in the response to salt stress. Our results provide important information for the biological function of C. equisetifolia, as well as offer candidate genes for further study of salt stress mechanism.