ACE Inhibitory Peptides from Bellamya bengalensis Protein Hydrolysates: In Vitro and In Silico Molecular Assessment

Bellamya bengalensis muscle meat is known for ethnopharmacological benefits. The present study focuses on the identification of ACE inhibitory peptides from the proteolytic digests of muscle protein of Bellamya bengalensis and its underlying mechanism. After ultrafiltration of 120 min alcalase hydrolysates (BBPHA120) to isolate the small peptide fraction (<3 kDa), in vitro ACE inhibitory activity was analyzed. The IC50 value of the 120 min hydrolysate ultrafiltered fraction was 86.74 ± 0.575 µg/mL, while the IC50 of lisinopril was 0.31 ± 0.07 µg/mL. This fraction was assessed in a MALDI-ToF mass spectrometer and five peptides were identified from the mass spectrum based on their intensity (>1 × 104 A.U.). These peptides were sequenced via de novo sequencing. Based on the apparent hydrophobicity (%), the IIAPTPVPAAH peptide was selected for further analysis. The sequence was commercially synthesized by solid-phase standard Fmoc chemistry (purity 95–99.9%; by HPLC). The synthetic peptide (IC50 value 8.52 ± 0.779 µg/mL) was used to understand the thermodynamics of the inhibition by checking the binding affinity of the peptide to ACE by isothermal titration calorimetry compared with lisinopril, and the results were further substantiated by in silico site-specific molecular docking analysis. The results demonstrate that this peptide sequence (IIAPTPVPAAH) can be used as a nutraceutical with potent ACE inhibition.

Boric acid toxicity in some selected molluscan species

: Survivability of animals is correlated with their fecundity and fertility success. Widespread use of enormous organic and inorganic ingredients as pesticides, molluscicides and insecticides contaminate ecosystems leading to hazardous effects on the life cycle of animals, their biological processes and reproduction. Present work aimed for toxicity assessment of boric acid against some selected molluscan species through evaluation of their mortality by determination of LC50. For toxicity assessment three different molluscan species were used. By applying standard procedure, LC50 was estimated at different concentrations of boric acid for different exposure periods. This study indicated that freshwater snail Bellamya bengalensis was more sensitive for boric acid, whereas slug, Semperula maculate was least sensitive against boric acid after different period of exposure.

Distribution of freshwater Mollusca in Koothaippar wetland ecosystem Tiruchirappalli District Tamil Nadu

Freshwater Mollusca form an important animal group of the wetland ecosystems. The distribution and availability in terms of number of species needs scientific attention. Present study is an attempt to document the available Molluscan forms in Koothaippar wetlands of Tiruchirappalli District. This study was carried out between summer 2013 to post-monsoon 2017. Nine species were recorded and among them 6 species belong to Gastropoda representing 2 orders, 3 families, 3 genera while 3 species were bivalves representing 1 order, 1 family and 2 genera. Bellamya bengalensis, Lamellidens marginalis and Pila globosa were the predominantly present molluscan fauna and are distributed throughout the year. Five species of Molluscan fauna (Pila virens, Pila scutata, Bellamya dissimilis, Indoplanorbis exustus and Lamellidens corrianus) are less abundant and Parreysia favidens was found to be rare species of the ecosystem. These Molluscan forms, representing different families ranging from 34% of Ampullariidae, 33% of Unionoida, 22% of Viviparoidae and 11% of Planorbidae. Percent distribution of these shelled organisms indicate that they represent 3 orders viz., 56% of Architaenioglossa, 33% of Unionoida and 11% of Hygrophila.

Protection against Mitochondrial Oxidative-Stress by Flesh-Extract of Edible Freshwater Snail Bellamya bengalensis Prevents Arsenic Induced DNA and Tissue Damage

Aims: Arsenic has carcinogenic properties because of the formation of Reactive Oxygen Species (ROS). ROS damages different macromolecules, tissues and organs, and severely exhausts cellular antioxidants. Background: Cytosolic and mitochondrial contribution of ROS production by arsenic are not well reported. In regard to the issues of therapy against arsenic or any other toxicity, natural product has gained its popularity due to its less side-effects and non-invasive nature. Objectives: Here, as an ethnomedicine, the flesh-extract (BBE; 100mg/100g bw) of Bellamya bengalensis (an aquatic mollusk) was applied in arsenic intoxicated (0.6 ppm/100g bw/for 28 days alone or in combination with BBE) experimental rats. Our objective was to study the anti-oxidative and anti-apoptotic role of BBE in hepato-gastrointestinal tissue damage by arsenic. Methods: DNA fragmentation assay, catalase activity (gel-zymogram assay) suggests that BBE has a strong protective role against arsenic toxicity, which is decisively demonstrated in hepatic histoarchitecture study by HE (hematoxylin and eosin) staining and by intestinal PAS (Periodic Acid Schiff) staining. Results: Measurement of mitochondrial-membrane-potential by fluorescent microcopy clearly demonstrated less membrane damage and lower release of the redox-active inner-membrane product (cytochrome-C, ubiquinone, etc.) in BBE supplemented group compared to that of the only arsenic fed group. The present study clearly suggests that mitochondrial disintegrity is one of the major causes of ROS mediated tissue damage by arsenic. Conclusions: This study also offers an option for prevention/treatment against arsenic toxicity and its carcinogenicity by widely available low-cost, non-invasive Bellamya extract by protecting cytoskeleton, DNA and mitochondria in the cell.

Use of Two Aquatic Snail Species as Bioindicators of Heavy Metals in Tigris River-Baghdad

Thirty individuals of Bellamya bengalensis and Physella acuta were collected and identified from the Tigris River in Baghdad during the period between October to November 2017. The efficiency of bioaccumulation of the two species as bioindicators for aquatic heavy metal pollution with Cd, Ni, Pb and Cu was investigated. Both snail species had the ability to accumulate heavy metals. The mean of Ni concentration in soft tissues of both snails was 1.53 ppm while the mean concentration of other heavy metals was significantly lower; they reached 0.51 ppm, 0.36 ppm and 0.29 ppm, respectively. While no significant differences between B. bengalensis and P.acuta were noticed in the ability to accumulate the heavy metals. It is concluded that both snails shared the features of good bioindicators due to their sensitivity to pollution.:

In vitro and in silico analyses of the angiotensin-I converting enzyme inhibitory activity of peptides identified from Bellamya bengalensis protein hydrolysates

The study focuses on identification of ACE-inhibitory peptides from the proteolytic digests of muscle protein of Bellamya bengalensis and its underlying mechanism. 120 min Alcalase-hydrolysates were ultrafiltered to isolate the small peptide fraction (<3kDa) and in vitro ACE-inhibitory activity was analyzed. The IC50 value of the 120 min hydrolysate ultafiltered fraction was found to be 86.74 ± 0.575 µg/mL, while the IC50 of Lisinopril is 0.31 ± 0.07 µg/mL. This fraction was assessed in MALDI-ToF mass-spectrometer and five peptides were sequenced via de novo sequencing. The ACE-inhibitory potential of the peptides have a positive correlation with the hydrophobicity of the amino acids. Synthetic analogue of the peptide (IC50 value 8.52 ± 0.779 µg/mL) was used to understand the thermodynamics of the inhibition by checking the binding affinity of the peptide to ACE by Isothermal titration calorimetry compared with lisinopril, and further substantiated by in silico site specific molecular docking study.