Heritiera Fomes Research Articles

15-lipoxygenase and serine protease inhibitory activities of Heritiera fomes (buch. -ham), a mangrove plant of the Sundarbans

15-Lipoxygenase (15-Lox) oxidizes fatty acid, thereby producing inflammatory mediators which cause diverse inflammatory diseases such as atherosclerosis, asthma, cancer etc. Serine proteases are enzymes that activate tissue factor VII by proteolytic cleavage, eventually activating blood coagulation pathway. Antioxidants play role in 15-Lox and serine protease inhibition to dampen elevation of cytokine levels, thereby function as anti-inflammation and anticoagulation agent. In this study, we examined 15-Lox and serine protease inhibitory activities of the ethanolic bark and leaf crude extract of Heritiera fomes. The crude bark extract (HFB) exhibited 15-Lox and serine protease inhibition with IC50 117.14 and 409.61 μg/ml, respectively. Chromatographically separated active fraction HFBPF1 demonstrated highest 15-Lox and serine protease inhibitory activity with IC50 62.68 and 72.62 μg/ml, respectively. The antioxidant activity and total flavonoid content were substantially increased in the chromatographic fractions compared to the crude extracts. The LC-MS/MS analysis of bark and leaf active fractions revealed the presence of 2,4,6-octatrienal, apigenin 7 (4˝-Z-p-coumerylglucoside), brosimacutin B, gambrin B2, kandelin A1 and tetraneurin A which we report for the first time in H. fomes. Therefore, we conclude the significant augmentation in the 15-Lox and serine protease inhibition activity of the fractions which could be exerted by the enriched flavonoid content.

Climate and salinity together control above ground carbon accumulation in the Sundarbans mangrove ecosystem

Mangroves play a crucial role in mitigating climate change through carbon (C) accumulation. Developing robust methods for the estimation of long-term C accumulation is essential for monitoring and reporting carbon financing projects under different global mechanisms. Moreover, understanding the effects of climate and habitat on C accumulation is important for developing mangrove management plans and conservation options. In this study, long-term above ground C accumulation in the three most dominated mangrove tree species, Heritiera fomes, Excoecaria agallocha and Sonneratia apetala, was estimated using a dendrochronological approach in two contrasting (low vs high) salinity zones in the Bangladesh Sundarbans. In addition, how climate and habitat (e.g., regulators and soil resources) influence C accumulation was analyzed. For the first time, we estimated C accumulation in mangrove species over their entire lifetime using stem disc-derived tree-ring data. The C accumulation patterns exhibited similar patterns of variation, increasing from pith to bark in each case. C accumulation was significantly higher in the low salinity zone (LSZ) than in the high salinity zone (HSZ) (p < 0.05). The cumulative C accumulation increased with tree age in each case, and C accumulation was influenced mainly by seasonal precipitation, especially during monsoon. General additive modeling (GAM) revealed that soil salinity had a stronger effect on C accumulation variability in the studied tree species. Other regulatory variables (i.e., siltation and elevation) and soil resources (i.e., P and K) had species-specific influences on C accumulation. Tree-ring data show the potential to yield better biomass and C estimations, which could aid frequent and rapid reporting of C accumulation in mangroves. Moreover, the results also suggest that climate and regulatory variables, especially soil salinity, together impact the C cycles in the Sundarbans.

Variation in soil organic carbon with structural composition of mangrove species in the Sundarbans

The world's biggest continual mangrove swampy land is the Sundarbans Mangrove Forest, which is crucial to both the terrestrial and marine carbon cycles. While numerous studies have focused on organic carbon variations within this ecosystem, few have explored the interaction between carbon stocks and the structural composition of mangrove species. This study sought to investigate the connection between soil organic carbon accumulation and functional attributes of vegetation (DBH, basal area). This study was carried out on four vegetative and two non-vegetative plots in three different sites within the oligohaline zone. Based on species Iv, the Karamjol area was prevalent by Heritiera fomes (Iv =139.3). In contrast, the Ghagramari area was predominated by Avicennia officinalis (IV =105.1). Accumulation of TBC, Avicennia officinalis presented the highest, despite having a smaller number of individuals within the study area. 1 m soil core was pulled out from each subplot of each main plot by using a one-meter-long open face peat auger. The forest areas exhibited maximum soil organic carbon accumulation, which was significantly (p < 0.01) higher than non-vegetative areas. Moreover, the mean soil C/N ratios in the Karamjol area (13.4±0.2) and Ghagramari area (13.2± 0.2) were significantly (p < 0.01) greater than those in the non-vegetative area (12.3±0.1). These findings suggest that regardless of the dominant species, species richness, or size (tall or dwarf) of the mangroves, a particular quantity of organic carbon is captured within the mangrove soil. Thus, when making future decisions, it is crucial to repute the role of the Sundarbans mangrove in the accumulation of organic and biomass carbon, which can directly affect mitigating global warming.

Exploring the Rich Diverse: Freshwater Fish Diversity and Bionomics in the Sundarbans, India

The Sundarban is a mangrove area in the deltaformed by the confluence of the gangas brahmaputra and meghna river in the Bay of Bengal. The hooghly river in india state of West Bengal to the baleswar river in bangladesh. It comprises closed and open mangrove forests agriculturally used land, mudflats and barren lands. It is intersected by multiple tidal streams and channels. Four protected area in the Sundarbans are enlisted as UNESCO WORLD HERITAGE SITES, Sundarbans national park,Sundarban west, east and south wildlife santuaries. The bengali name Sundarban is beautiful forest. It may have benn derived from the word sundari, the local name of the mangrove sp Heritiera fomes. There many biodiversity like 453 faunal wildlife, including 290 birds,120 fish, 42 mammal, 35 reptiles and 8 amphibians. The goal of this review paper is discussing about freshwater fish diversity and its bionomics in Sundarban delta. Also about the a brief description of study area (Sundarban) encompassing definition of a mangrove ecosystem, importance of mangrove ecosystem, area and distribution of Sundarban; Indian Sundarban – area, location, fisheries related activities; importance of studying fish diversity. And try to generate a data base on some of the life history parameters and their conservation status and atlast study threats associated with fish diversity measures for sustainable fishery.

The Environmental Impact Analysis for Three Mangrove Species of Indian Sunderbans

The paper deals with three mangrove species of Indian Sunderbans namely, Heritiera fomes Bach.-Him, Nypa fruticans Wamb. and Acrostichum aureum L. which have become endangered due to different environmental impact of them. The main factors causing rapid decrease in the population of these three species are (i) Lack of fresh water supply, (ii) Human population pressure, and (iii) Over exploitation. The problem has been assessed and measures suggested to save the three species.

Floral scents, specialized metabolites and stress-response activities in Heritiera fomes and Bruguiera gymnorrhiza from Sundarban mangrove ecosystem.

Floral biochemistry and stress physiology is an underexplored aspect of mangroves, which should be investigated as part of preservation and restoration efforts. A thriving true mangrove tree (Bruguiera gymnorrhiza (L.) Lamk.) and a threatened mangrove-associate species (Heritiera fomes Buch. Ham.) were studied in the Sundarban region of India for seasonal variations in floral odours, non-volatile phytochemicals, antioxidant enzyme activities, and surface water chemistry in surrounding habitat. Both species were found to exhibit significant differences in floral volatilomes, protein contents, antioxidant enzyme activities, total flavonoids, and total phenolic contents between spring and autumn blooms. The bird-pollinated flowers of B. gymnorrhiza also showed considerable seasonal differences in floral anthocyanin and proline contents, indicating vulnerability of the post-anthesis open flowers to environmental factors. Contrarily to previous findings, B. gymnorrhiza floral bouquet appeared to be enriched in various classes of volatiles - dominated by sulphurous compounds in bud stage and terpenoids in open stage. Floral anthocyanins, contributing to the striking colouration of the calyx, were found to comprise cyanidin and delphinidin derivatives. Other glycosides of cyanidin and delphinidin were detected in H. fomes flowers, contributing to visual guides to potential food rewards for pollinating insects. Floral tissue in H. fomes was found to be protected by densely overlapping layers of stellate trichomes containing sesquiterpenoids as phytoprotectants. Comparison of the two floral species suggested that H. fomes flowering is optimized to oligohaline (but not freshwater) vernal conditions; whereas B. gymnorrhiza blooms are adapted for biologically enriched (including abundant herbivores and microbial growth), mesohaline forest habitats.

Identification of natural antiviral drug candidates against Tilapia Lake Virus: Computational drug design approaches.

Tilapia Lake Virus (TiLV) is a disease that affects tilapia fish, causing a high rate of sudden death at any stage in their life cycle. Unfortunately, there are currently no effective antiviral drugs or vaccines to prevent or control the progression of this disease. Researchers have discovered that the CRM1 protein plays a critical function in the development and spreading of animal viruses. By inhibiting CRM1, the virus's spread in commercial fish farms can be suppressed. With this in mind, this study intended to identify potential antiviral drugs from two different tropical mangrove plants from tropical regions: Heritiera fomes and Ceriops candolleana. To identify promising compounds that target the CRM1 protein, a computer-aided drug discovery approach is employed containing molecular docking, ADME (absorption, distribution, metabolism and excretion) analysis, toxicity assessment as well as molecular dynamics (MD) simulation. To estimate binding affinities of all phytochemicals, molecular docking is used and the top three candidate compounds with the highest docking scores were selected, which are CID107876 (-8.3 Kcal/mol), CID12795736 (-8.2 Kcal/mol), and CID12303662 (-7.9 Kcal/mol). We also evaluated the ADME and toxicity properties of these compounds. Finally, MD simulation was conducted to analyze the stability of the protein-ligand complex structures and confirm the suitability of these compounds. The computational study demonstrated that the phytochemicals found in H. fomes and C. candolleana could potentially serve as important inhibitors of TiLV, offering practical utility. However, further in vivo investigations are necessary to investigate and potentially confirm the effectiveness of these compounds as antiviral drugs against the virus TiLV.

What drives carbon stocks in a mangrove forest? The role of stand structure, species diversity and functional traits

Mangrove forests provide a variety of ecosystem services, and among them, the ability to sequester large quantities of below-ground carbon reservoirs is considered the most critical service for mitigating climate change. Therefore, most mangrove studies are highly concerned with estimating ecosystem carbon stocks, while only a few studies have focused on the factors driving these carbon stocks. Thus, we examined the role of stand structure, species diversity, and functional traits on above-ground, below-ground, and total carbon stocks using data from 28 sample plots from the low salinity zone of the Sundarbans mangrove forest of Bangladesh. We also aimed to understand the distribution patterns of carbon stocks among different components of the ecosystem, such as above-ground, below-ground soil, and roots. The study results revealed that tree height, diameter at breast height (DBH), and basal area were highly correlated with both above-ground (AGC) and below-ground carbon (BGC, incuding soil carbon at 0–50 cm depth) stocks. Multiple regression models indicated that tree height and basal area were two significant positive predictors for AGC, BGC and total carbon stocks (TCS) (p < 0.05). Species richness and community-weighted mean wood density were significant positive predictors for BGC and TCS. In contrast, Simpson diversity and community-weighted mean specific leaf area negatively influenced BGC. Furthermore, we observed that the above-ground tree carbon (AGTC = 80.4 ± 32.0 Mg ha−1) was significantly higher than below-ground soil carbon to 50 cm depth (BGSC-50 cm = 41.0 ± 5.4 Mg ha−1), followed by below-ground root carbon (BGRC = 37.1 ± 10.1 Mg ha−1), pneumatophore (Pneu_C = 28.8 ± 18.8 Mg ha-1), and downed wood (DW = 0.03 ± 0.02 Mg ha−1) (p < 0.05). In terms of specific species contribution, Heritiera fomes contributed the most to AGTC and BGRC, followed by other species such as Avicennia officinalis > Excoecaria agallocha > Sonneratia apetala > Xylocarpus mekongensis > Bruguiera sexangula. Our findings indicate that maintaining dominant trees (H. fomes) and a diverse stand can be an effective way to enhance carbon stocks in a mangrove ecosystem.

Fine Root Production and Its Benefaction to carbon storage of the Sundarbans Mangrove Forest

The quantification of fine root production (FRP) and biomass (FRB) is of utmost importance in gaining insights into ecosystem dynamics. However, these aspects have received limited attention in mangrove forests, primarily due to the considerable time and labor required for accurate assessment. Therefore, our study aims to estimate FRP and FRB stocks in the Sundarbans mangrove forest in Bangladesh, specifically focusing on two distinct saline zones: oligohaline and mesohaline. To accomplish our objectives, we employed soil coring and long-term ingrowth core methods to collect soil samples from 20 study plots, each covering an area of 200 square meters. Additionally, we assessed the forest structure by measuring the tree height and diameter at breast height. Our findings revealed that the mean FRB and FRP across the study area were 12.65±1.12 Mgha-1 and 2.25±0.13 Mgha-1 y-1, respectively. Notably, the oligohaline zone, characterized by lower salinity levels, exhibited higher FRB stocks and FRP compared to the mesohaline zone. Furthermore, our analysis showed that FRP in the diameter class of 1-2 mm surpassed that of the 0.5-1 mm and ≤0.5 mm classes. In terms of biomass, the mean above-ground, below-ground, and total biomass carbon were determined to be 87.18 ± 18.3, 48.38 ± 8.0, and 135.57 ± 26.3 Mgha-1, respectively. Through species importance value (Iv) analysis, we identified Excoecaria agallocha as the dominant species in the oligohaline zone, while Sonneratia apetala exhibited the highest Iv value in the mesohaline area. Heritiera fomes emerged as the primary contributor to total biomass carbon, particularly in the oligohaline zone, whereas S. apetala contributed the most biomass carbon in the mesohaline zone. These findings emphasize the importance of protecting and conserving mangrove ecosystems as valuable contributors to global carbon dynamics due to its higher fine root production and its contribution to carbon stocks.

Evolution of sea-surfing plant propagule as revealed by the genomes of Heritiera mangroves.

Coastal forests, such as mangroves, protect much of the tropical and subtropical coasts. Long-distance dispersal via sea-surfing propagules is essential for coastal plants, but the genomic and molecular basis of sea-surfing plant propagule evolution remains unclear. Heritiera fomes and Heritiera littoralis are two coastal plants with typical buoyant fruits. We de novo sequenced and assembled their high-quality genomes. Our phylogenomic analysis indicates H. littoralis and H. fomes originated (at ~6.08 Mya) just before the start of Quaternary sea-level fluctuations. Whole-genome duplication occurred earlier, permitting gene copy gains in the two species. Many of the expanded gene families are involved in lignin and flavonoid biosynthesis, likely contributing to buoyant fruit emergence. It is repeatedly revealed that one duplicated copy to be under positive selection while the other is not. By examining H. littoralis fruits at three different developmental stages, we found that gene expression levels remain stable from young to intermediate. However, ~1000 genes are up-regulated and ~ 3000 genes are down-regulated as moving to mature. Particularly in fruit epicarps, the upregulation of WRKY12 and E2Fc likely constrains the production of p-Coumaroyl-CoA, the key internal substrate for lignin biosynthesis. Hence, to increase fruit impermeability, methylated lignin biosynthesis is shut down by down-regulating the genes CCoAOMT, F5H, COMT, and CSE, while unmethylated lignins are preferentially produced by upregulating CAD and CCR. Similarly, cutin polymers and cuticular waxes accumulate with high levels before maturation in epicarps. Overall, our genome assemblies and analyses uncovered the genomic evolution and temporal transcriptional regulation of sea-surfing propagule.

LEAF PIGMENT AND TOTAL CARBOHYDRATE CONTENT AT EARLY STAGES OF HERITIERA FOMES BUCH. SEEDLINGS GROWN AT THREE SALINE ZONES OF THE SUNDARBANS, BANGLADESH

The experiment was conducted to find the leaf pigments and carbohydrate content in Heritiera fomes at different growth stages exposed to different salinity levels in the Sundarbans areas, Bangladesh. Three leaf pigments, viz., chlorophyll a, chlorophyll b, and carotenoid, total chlorophyll, and total carbohydrate content of Heritiera fomes Buch. Ham seedlings were determined in the leaves grown in the oligohaline, mesohaline, and polyhalite zones at early (6 and 9 months) and survival ages (30 months) following standard methods. Leaves from seedlings at the age of 30 months (survival aged) show relatively high leaf pigments than that of the 6 and 9-month-old seedlings grown in the three saline zones. Total chlorophyll content in leaves was found low in the oligohaline zone at the early and survival ages, but higher in the polyhalite zone at the early ages, and higher in the mesohaline zone at the survival age. Chlorophyll b was relatively higher than chlorophyll a. Leaves of 30 months seedlings showed relatively higher chlorophyll a than chlorophyll b at the polyhalite zone, but higher chlorophyll b was noted at the mesohaline zone. The highest content of total carbohydrates was observed in the shoots of 6, 9, and 30 months ages H. fomes seedlings in the polyhalite zone, while the lowest was in the mesohaline zone. At the same age periods in the mesohaline zone, the roots of the H. fomes seedlings showed relatively higher carbohydrate content and lower at the 30 months seedlings in the all saline zones. Chlorophyll a was found to be more sensitive than chlorophyll b and carotenoid at different salinity levels tested. Higher carbohydrate content was discovered as an additional mechanism to prevent salt toxicity at early ages of high saline conditions (polyline zone).

Cytotoxicity against human cancer cells and lymphocytes based on cerium oxide nanostructures

Nanomedicine has emerged as a promising avenue for targeted cancer therapy, aiming to develop innovative approaches with improved efficacy and reduced side effects. CeO2 Nanostructures (CeO2 NSs) have attracted considerable attention in biomedical research due to their unique physicochemical properties and potential applications in cancer therapy. In the present article, we studied various methods of synthesis of biocompatible cerium oxide nanoparticles through phyto synthesis (CeO2-P) using Heritiera fomes plant extract and the chemical reducing method (CeO2-C). As obtained, CeO2-P and CeO2-C were characterized using XRD (X-ray diffraction), FTIR(Fourier Transformation Infrared spectroscopy), UV-Visible spectroscopy, and field emission scanning electron microscopy. Further, cytotoxic activity was studied on human cancer cell lines – MDA-MB-231-human breast cancer cell line; HeLa -human cervical cancer cell line; HCT-116- human colon cancer cell line, and human blood mononuclear cells (lymphocytes). A comparative study evaluating the induction of apoptosis by CeO2-P and CeO2-C was performed using propidium iodide staining on the mentioned human cancer cell lines. Toxicity assessment results showed the better performance of CeO2-P nanoparticles against HCT-116 at an IC50 concentration of 6.37 μg/mL compared to CeO2-C nanoparticles (HCT-116 - 8.08μg/mL). Similarly, the CeO2 nanoparticles showed significant cytotoxicity against Hela and MDA-MB-231 cells after 24 h treatments. Interestingly, CeO2-P nanoparticles are less toxic to human blood lymphocytes than CeO2-C nanoparticles. Furthermore, propidium iodide staining revealed the signs of apoptosis in all three human cancer cell lines treated with CeO2-P compared to CeO2-C nanoparticles. In conclusion, these findings provide valuable insights into the potential use of CeO2 nanostructures as a promising therapeutic agent in cancer treatment while exhibiting minimal toxicity towards lymphocytes. Further investigations are warranted to explore the underlying mechanisms and optimize the therapeutic efficacy of CeO2 Nanostructures for targeted cancer therapy.

Pharmacological effect of Heritiera fomes on Long Evans rats against Postprandial Hyperglycemia and adsorption in vitro.

Natural restoratives from traditional medicinal plants are considered to be a convenient, potent, and risk-free substitute treatment for hyperglycaemia. Our objective was to explore the activity of the crude extract of Heritiera fomes on postprandial hyperglycaemia by assessing relative measurements in a laboratory animal model. The Streptozotocin induced diabetic rat (n = 88, twenty-two per group) was used for the glucose tolerance test as an initial support for the study. BaSO4was administered orally as a marker to measure gut motility after one hour of methanolic extract (500mg/kg body weight) administration where, only purified water (10 ml/kg) was used to treat the control group (n = 12) and a dose (500mg/kg) of H. fomes extract was used for the test group (n = 12 in each group). After 60min of incubation of the mixture of extract and glucose with 10% (v/v) yeast cell suspension, the absorbance was measured to determine the capacity of glucose absorption by yeast cells. Sixty Long Evans rats (n = 12 in each group) were used to assess disaccharidase enzyme activity as µmol/mg protein per hour by Lowry's protein estimation method. The carbohydrate absorption investigation was executed to evaluate the leftover sucrose content in the gastrointestinal system (n = 64). After oral administration of MHFL (71.84%), MHFB (71.41%), and MHFR (72.55%), GI motility (%) increased significantly (p < 0.001) compared to the control group (59.06%). A significant increase in glucose uptake and adsorption capacity measured by different concentrations of glucose ensures the decrease of glucose bound rate and a significant drop in blood glucose concentration. The significant (p < 0.001) decrease in intestinal disaccharidase activity of MHFL (1.40), MHFB (1.36), and MHFR (1.20) in comparison to the control group (1.50) indicates that the presence of H. fomes may reduce glucose absorption in the small bowel. Significant (p < 0.001 & p < 0.05) accumulation of sucrose content in the six different parts of the GI tract suggests the absorption of sucrose was decreased. The findings of this study provide evidence on probable mechanisms for the anti-diabetic characteristics of H. fomes, and it is predicted that this plant will be studied further for the development of strong anti-hyperglycemic medicines.

STATUS OF REGENERATION OF MAJOR TREE SPECIES IN THE SUNDARBANS

Status of regeneration of 30 tree species in the Sundarbans has been provided based on data generated from 1203 Temporary Sample Plots (TSPs) during the Forest Resources Management Project (FRMP) Forest Inventory of the Sundarbans in 1996 and 1997. The extents of occurrence of individual species and mean number of seedlings and saplings per hectare have been provided which represents the whole of the Sundarbans. It was found that sundri (Heritiera fomes) constituted 54.92 % seedlings and 28.73 % saplings, while it was respectively 16.23 % and 19.64 % for gewa (Excoecaria agallocha) as well as 16.52 % and 44.36 % for goran (Ceriops decandra). Other species provided 12.33 % seedlings and 7.27 % saplings. Regeneration status of sundri, gewa, goran and amur (Amoora cuculata) of 1996-97 was compared with the data generated in January 2003 from 36 Sample Plots in 10 compartments of the Sundarbans. Comparison revealed that there occurred significant (p=0.05) increase in sundri and amur seedlings in 2003 as compared to 1996-1997 level.

Salinity reduces site quality and mangrove forest functions. From monitoring to understanding

Mangroves continue to be threatened across their range by a mix of anthropogenic and climate change-related stress. Climate change-induced salinity is likely to alter the structure and functions of highly productive mangrove systems. However, we still lack a comprehensive understanding of how rising salinity affects forest structure and functions because of the limited availability of mangrove field data. Therefore, based on extensive spatiotemporal mangrove data covering a large-scale salinity gradient, collected from the world's largest single tract mangrove ecosystem – the Bangladesh Sundarbans, we, aimed to examine (QI) how rising salinity influences forest structure (e.g., stand density, diversity, leaf area index (LAI), etc.), functions (e.g., carbon stocks, forest growth), nutrients availability, and functional traits (e.g., specific leaf area, wood density). We also wanted to know (QII) how forest functions interact (direct vs. indirect) with biotic (i.e., stand structure, species richness, etc.) and abiotic factors (salinity, nutrients, light availability, etc.). We also asked (QIII) whether the functional variable decreases disproportionately with salinity and applied the power-law (i.e., Y = a Xb) to the salinity and functional variable relationships. In this study, we found that rises in salinity significantly impede forest growth and produce less productive ecosystems dominated by dwarf species while reducing stand structural properties (i.e., tree height, basal area, dominant tree height, LAI), soil carbon (organic and root carbon), and macronutrient availability in the soil (e.g., NH4+, P, and K). Besides, species-specific leaf area (related to resource acquisition) also decreased with salinity, whereas wood density (related to resource conservation) increased. We observed a declining abundance of the salt-intolerant climax species (Heritiera fomes) and dominance of the salt-tolerant species (Excoecaria agallocha, Ceriops decandra) in the high saline areas. In the case of biotic and abiotic factors, salinity and salinity-driven gap fraction (high transmission of light) had a strong negative impact on functional variables, while nutrients and LAI had a positive impact. In addition, the power-law explained the consistent decline of functional variables with salinity. Our study disentangles the negative effects of salinity on site quality in the Sundarbans mangrove ecosystem, and we recognize that nutrient availability and LAI are likely to buffer the less salt-tolerant species to maintain the ability to sequester carbon with sea-level rise. These novel findings advance our understanding of how a single stressor—salinity—can shape mangrove structure, functions, and productivity and offer decision makers a much-needed scientific basis for developing pragmatic ecosystem management and conservation plans in highly stressed coastal ecosystems across the globe.

Stand structure, tree species diversity, and leaf morphological plasticity in Xylocarpus mekongensis Pierre among salinity zones in the Sundarbans, Bangladesh

Stand structure, diversity, and plasticity of leaf morphology of Xylocarpus mekongensis were investigated among saline zones in Bangladesh Sundarbans. Stand structure and species diversity were assessed in 27 sample plots (20 m× 20 m) covering 1.08 ha of forest. A total of 11 species were recorded. Out of them, 7, 6, and 9 species were found in fresh water, moderate, and strong saline zone, respectively. Species dominance in terms of importance value showed Heritiera fomes > Excoecaria agallocha > Bruguiera sexangula > Xylocarpus mekongensis in fresh water zone; H. fomes > E. agallocha > Avicennia officinalis > Ceriops decandra in moderate saline zone. E. agallocha > Sonneratia apetala > H. fomes > C. decandra in strong saline zone. Species diversity decreased from fresh water to strong saline zone. The findings showed a wide range of leaf morphological plasticity of all the parameters within and among saline zones. Leaf index, plasticity index, and specific leaf area were maximum in fresh water zone than of others. The findings of PCA revealed clear evidences of plastic behavior of leaf morphological parameters. Thus, the plasticity of leaf morphology might contribute as an influential biological signs of forthcoming climate change events. • We investigated the effect of saline zone on stand structure and diversity on mangrove species in the Sundarbans. • We also investigated leaf index, leaf plasticity index, and specific leaf area among saline zones of Bangladesh Sundarbans. • Tree species diversity decreased from fresh water zone to strong saline zone. • Xylocarpus mekongensis showed high level of leaf morphological plasticity within and among saline zones.

Dominant species losing functions to salinity in the Sundarbans Mangrove Forest, Bangladesh

Globally, mangrove forests are deteriorating due to several natural and anthropogenic factors such as sea level rise, habitat fragmentation, over-exploitation, pollution, etc. Sea-level rise - driven salinity would influence the functional activity of dominant species by declining their structure and functions, which is not well understood. Therefore, we tried to understand the increased salinity impact on the structures and functions of two identified dominant mangrove species (i.e., Excoecaria agallocha and Heritiera fomes) in the Sundarbans Mangrove Forest (SMF), Bangladesh. We test our hypothesis that salinity significantly retards the functions of dominant species structure and functions by evaluating two consecutive years of inventory data from 60 permanent sample plots (100 m2 each) established in three distinct salinity zones in the SMF. The study revealed that structural parameters of dominant species such as tree height, diameter at breast height (DBH), and basal area decreased in higher saline zones than in less saline zones. E. agallocha and H. fomes stored more biomass and carbon in less saline and moderate saline zones compared to high saline zone. Besides, functional variables such as above-ground biomass carbon and total biomass carbon decreased with salinity for both dominant species. This study demonstrated that salinity shapes dominant species by declining their height, DBH, growth, etc., which indicates salinity is a critical discriminating variable for losing species’ stand structures and functions. This information is critica to determine the physiological response of dominant species across the globe, which is crucial to predicting future climate change impacts such as sea-level rise.

Phytochemical and Pharmacological Profiling of Heritiera fomes Buch. Ham. Deciphered Thrombolytic, Antiarthritic, Anthelmintic, and Insecticidal Potentialities via In Vitro Approach.

Medicinal plants have been crucial in treating various chronic ailments since ancient times. The objective of this study was to evaluate in vitro pharmacological properties of petroleum ether, chloroform, and ethyl acetate soluble fractions of ethanolic extract (leaf, bark, and root) of Heritiera fomes Buch. Ham., including the phytochemical screening of the plant. Thrombolytic and antiarthritic properties were assessed through the clot lysis and protein denaturation experimental method, correspondingly. Anthelmintic and insecticidal activities were studied against Pheretima posthuma and Tribolium castaneum, respectively. The phytochemical analysis exhibited numerous active phytochemicals in different solvent fractions. In thrombolytic investigation, among all crude extracts, ethanolic leaf extract showed the highest 33.12 ± 7.52% clot lysis as compared to standard streptokinase (67.77 ± 9.78%). In antiarthritic assay, all the tested samples exhibited noteworthy protein denaturation in dose-dependent manner (100–500 μg/mL), whereas the utmost percentage inhibition was noticed for chloroform extract of roots (63.28 ± 5.96% at 500 μg/mL). All crude extracts exhibited a significant anthelmintic activity in different concentrations (25–75 mg/mL) and revealed paralysis and death of earthworms in comparison with albendazole; ethanolic extract of the bark was found to be more potent at the highest dose. For the insecticidal test, ethanolic extract of the leaf showed the utmost mortality rate (73%). The outcomes of the investigation confirmed the potential thrombolytic, antiarthritic, anthelmintic, and insecticidal activities of the different extracts of H. fomes, and hence, advanced studies on the isolation and identification of active phytocompounds are highly needed for new drug development.

ANTIOXIDANT ACTIVITY AND CAPACITY OF SILVER NANOPARTICLES BIOSYNTHESIS OF COMMON FRUITS AQUEOUS EXTRACTS OF THE SUNDARBAN FOREST

Fruits provide numerous health-promoting polyphenols and antioxidants. The Sundarbans mangrove forest of Bangladesh produces various fruits, and off them ten to twelve are known to be consumed or used as an ingredient in food preparations. These fruits were used in this study to evaluate the total polyphenols (TPH) contents following the method of Folin-Ciocalteu’s; and the antioxidant activity by measuring 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals scavenging, reducing power and total antioxidant capacity. Additionally, capacity of silver nanoparticles (AgNPs) biosynthesis of the fruits was determined spectrophotometrically. Sonneratia apetala fruit showed the highest TPH content (45.7 mg of gallic acid equivalent (GAE)/g powder). The fruit also showed the largest antioxidant activity attributed to the DPPH free radicals scavenging, reducing power, and total antioxidant capacity. Additionally, S. apetala fruit showed the highest capacity in the AgNPs biosynthesis (OD, 0.41; 10 mg powder/mL). Avicennia officinalis, Ceriops decandra, Heritiera fomes, and S. apetala fruits showed scavenging of 50% DPPH free radicals at 81, 34.7, 61.2, and 33.5 µg powder/mL, respectively. Contents of total polyphenols in these fruits displayed strong positive correlations with reducing power (r2 = 0.97), total antioxidant capacity (r2 = 0.85) and scavenging DPPH free radicals (r2 = 0.85) whereas that for the AgNPs biosynthesis capacity was small (r2 = 0.32). Thus, the aqueous extract of S. apetala fruit is the most potential in antioxidant activity and biosynthesis of AgNPs.

Effect of mangrove leaf litter on shrimp (Penaeus monodon, Fabricius, 1798) growth and color

Color, texture and flavor are all important determinants of seafood product quality and value. For shrimp, Penaeus monodon, one of the highest-priced shrimp species of the South-East Asia shrimp industry, dark tiger-striped coloration is a key product quality criterion. We evaluated the effects of leaf litter of the mangrove species Avicennia officinalis (AO), Heritiera fomes (HF), Sonneratia apetala (SA) and S.caseolaris (SC) on length, weight and body color of shrimp (Penaeus monodon) post-larvae (PL). Fifteen-day-old PL (weight: 0.01 g) were reared in 1100-L fiber-reinforced polyethylene tanks. Five treatments having three replications were conducted for four weeks. Four treatments received leaf litter of the four mangrove species and supplemental feeds and one control treatment was provided with supplemental feed only (FO). The pH, biological oxygen demand (BOD5), chemical oxygen demand (COD) and phytoplankton and zooplankton biomass were lower, while total ammonia nitrogen (TAN) concentration were significantly higher in the FO treatment than in treatments including leaf litter. PL survival averaged 89% and only differed significantly between the SA and SC leaf litter treatments (p < 0.05). After 4 weeks of culture, larvae in the FO treatment had significantly shorter body and carapace length, lower body weight and a lower specific growth rate than larvae in the other treatments, while SA-reared larvae attained significantly greater length and weight than in the other leaf litter treatments. Shrimp body coloration and pattern with leaf litter treatments were significantly different from the FO treatment. SA-reared larvae at harvest were significantly darker in body color than larvae reared with other mangrove species. Shrimp value chain stakeholders preferred dark shrimp as an indicator of organic production and higher price. Mangrove leaf litter was found to enhance the production and color quality of black tiger shrimp and this technique can be applied in commercial shrimp aquaculture.