Indian White Shrimp Fenneropenaeus Indicus Research Articles

Inhibition of Melanosis and Quality Changes on Indian White Prawn Treated with Lemon and Pomelo Peel Extracts Conjugated with Copper Sulfide Nanoparticles during Chilled Storage

ABSTRACT The study was aimed at the assessment of lemon peel extract (LPE) and pomelo peel extract (PPE) conjugated with copper sulfide nanoparticles (CuSNPs) influence on melanosis formation and improving the quality of chilled stored Indian white shrimp (Fenneropenaeus indicus) after 15 days. Biochemical indices, microbial count, and sensory analysis was performed at 3 day intervals. The trimethylamine, total volatile base nitrogen, free fatty acid, and peroxide value of control was 18.01 ± 0.79 mgN/100 g, 45.08 ± 1.1 mgN/100 g, 0.14 ± 0.01% of oleic acid, and 16.42 ± 0.612 milliequivalents/kg, whereas LPE+PPE+CuSNPs was 10.94 ± 1.04 mgN/100 g, 17.51 ± 1.1 mgN/100 g, 0.091 ± 0.01% of oleic acid, and 7.57 ± 0.38 milliequivalents/kg, respectively, at the 15th day of storage. The biochemical indices, microbial count, and sensory score of the treated sample was significantly lower (P < .05) than the untreated sample at day 15. This study aimed to determine the effectiveness of this biopreservation technique, which could provide a new alternative in preservation techniques, as well as impact shelf life and product safety.

Microplastic Abundance in Blood Cockles and Shrimps from Fishery Market, Songkhla Province, Southern Thailand

Microplastics have been one of the major pollutants in the marine environment throughout the recent decade. At present, microplastic contamination in marine ecosystems of Thailand region has become an increasing environmental concern because the ingestion of microplastics in marine organisms may adversely influence the safety of seafood. Cockles and shrimps widely distribute among marine organisms in Thailand since they are one of the commercial sources of seafood, which may be a route of exposure to microplastics towards human. This study documents a market survey in order to understand the extension of microplastic presence in blood cockles (Anadara granosa), fine shrimp (Metapenaeus elegans) and Indian white shrimp (Fenneropenaeus indicus) sold in the fishery market in Singhanakorn district, Songkhla province. These selected species are widely consumed and economically important, especially in the southern Thailand region. The total microplastic concentration in blood cockles is 4.71±0.06 n/g (wet weight) and 2.64±0.01 n/individual; in fine shrimp is 0.50±0.19 n/g (wet weight) and 3.70±1.12 n/individual; in Indian white shrimp is 0.69±0.48 n/g (wet weight) and 3.45±0.04n/individual. Discovered microplastics in all the species samples were mainly composed of microplastic fibres and black colour was found to be more predominant. Our results indicate that microplastic contamination is present in Thailand’s commercial seafood species. As microplastic able to be transferred to human through food web, we suggest further market-based survey studies on other seafood sources.

Evidence of Marine Microplastics in Commercially Harvested Seafood.

Microplastic pollution is a global issue that has a detrimental impact on food safety. In marine environments, microplastics are a threat to marine organisms, as they are often the same size range as prey and are mistaken as food. Consumption of microplastics has led to the damage of digestive organs and a reduction in growth and reproductive output. In this study, microplastic pollution was assessed across three commercially available shrimp species that were obtained from the supermarkets of Singapore. A total of 93 individuals were studied from the Pacific white leg shrimp, Litopenaeus vannamei, the Argentine red shrimp Pleoticus muelleri and the Indian white shrimp Fenneropenaeus indicus. Microplastic fibers, fragments, film and spheres were identified from the digestive tract of these organisms. Microplastic abundance ranged from 13.4 to 7050 items. F. indicus exhibited the highest number of microplastics. Microplastic film was the most abundant in L. vannamei individuals (93–97%) and spheres were the most abundant in P. muelleri (70%) and F. indicus (61%) individuals. This study demonstrates that microplastic contamination is evident in commonly consumed shrimp and highlights the role of shrimp in the trophic transfer and accumulation of microplastics in seafood. The consumption of microplastic-containing seafood is a route of exposure to humans and has implications on human health and food security. Capsule: Microplastics were examined in three shrimp species from the supermarkets of Singapore. Microplastics ranged from 13.4 to 7050 items of shrimp.

Molecular, histopathologic and electron microscopic analysis of white spot syndrome virus in wild shrimp (Fenneropenaeus indicus) in the coastal waters of Iran.

So far, there have been no studies on the distribution of viral white spot syndrome in wild Indian white shrimp (Fenneropenaeus indicus) brooders at Iranian capture sites. This study was conducted to investigate the presence of white spot syndrome virus (WSSV) in wild Indian white shrimps in Iran, using PCR, histopathologic, and electron microscopic surveys. The samples were collected within two seasons (autumn and spring) and from two provinces (six capture sites), from the major hatcheries providing spawners. Eight hundred thirty-three samples were collected and analyzed first by PCR, after which the positive samples were examined using histological tests, and if inclusion bodies were observed, electron microscopy was also used. White spot syndrome virus was detected only at the capture sites in Sistan and Baluchistan Province, where the mean infection rate was significantly higher in the spring (8.7%) than in the autumn (2.03%). At the Chabahar, Pasabandar, and Govater capture sites, the mean infection rate was significantly higher (4.9%, 2.1%, and 9.2%, respectively), than in Hormozgan Province. The results showed that there was no significant difference in infection rate between the two different sizes and sexes of shrimps (P < 0.05). Phylogeny analysis revealed a close relationship between the viruses from this study and those in other Asian countries, including China, India, Bangladesh, Thailand, Taiwan, and South Korea. It is possible that the virus has spread across the Indian Ocean to other countries. Therefore, the spawners in this study, particularly those collected during the spring and those from capture sites in Sistan and Baluchistan Province, were found to be more susceptible to WSSV infection, and the virus might have been transmitted vertically from WSSV-infected brooders to post-larvae.

New insights from nuclear and mitochondrial markers on the genetic diversity and structure of the Indian white shrimp Fenneropenaeus indicus among the marginal seas in the Indian Ocean

Genetic variation in wild stocks of a major commercial shrimp, Fenneropenaeus indicus, from the marginal seas in the Indian Ocean was analysed using polymorphic microsatellite loci and mitochondrial COI gene. The average observed heterozygosity (Ho = 0.44 ± 0.02) and the expected heterozygosity (He = 0.73 ± 0.01) were high across loci and populations indicating high microsatellite variation. Pairwise FST and Bayesian clustering indicated the occurrence of four genetically distinct stocks out of the eight sampled populations with implications for specific management approaches. Mantel test for isolation by distance proved that genetic differentiation is not related to geographic distance between populations. Mitochondrial COI sequence analysis showed concordant differentiation pattern as well indicated the relevance of COI in population genetics of shrimps. Pairwise ɸST and phylogenetic and Bayesian analyses revealed four distinct clades, as observed with nuclear markers. Divergence time analysis revealed the origin and initial divergence of F. indicus corresponds to late Miocene and divergence to phylogroups in the Pleistocene. BSP analysis presented a long stable population size with a slight decrease in the late Pleistocene and gradually expanded to the current status. The information here will be useful in commercial shrimp breeding and selection programmes and management of natural stocks of Indian white shrimp.

EFFECT OF PROBIOTICS AND CARBON SOURCES ON GROWTH PERFORMANCE AND SURVIVAL OF INDIAN WHITE SHRIMP (FENNEROPENAEUS INDICUS) UNDER BIOFLOC TECHNOLOGY

The aim of this study was to determine the influence of different sources of carbon with and without addition of probiotics on growth performance, and feed utilization of Indian white shrimp (Fenneropenaeus indicus), in addition to water quality of biofloc production system. Control diet (35% CP), in addition to eight treatments based on partial and complete substitution of artificial feeds were used. The biofloc used in the treatments were collected from different reactors with different carbon source (Corn flour and Barley flour) with and without probiotics addition. The experiment lasted for 28 days. At the end of the experiment, the results indicated that there were significant differences between treatments in growth performance and feed utilization. The highest survival was shown by the shrimp fed with barley flour fed biofloc without probiotics and control treatments (100 ± 0.0%), while the lowest survival was shown by the shrimp fed with corn flour fed biofloc with probiotics (54 ± 1.0%). The highest specific growth rate was obtained in the control treatment (1.66 ± 0.02%) while, the shrimp fed with biofloc from barley flour carbon source without probiotics showed almost similar specific growth rate (1.61± 0.02) to that of the control treatment. The biofloc fed shrimp showed promising growth values indicating that the biofloc was sufficient for supporting shrimp growth under commercial farming conditions. Hence, the overall experiments allow concluding that based on its nutritional value; the biofloc offers an alternative strategy for an efficient use of nutrient input in aquaculture systems.

Genetic parameters of survival in four generations of Indian white shrimp (Fenneropeneaus indicus)

ABSTRACT This study evaluated the genetic variance for survival at harvest of Indian white shrimp (Fenneropenaeus indicus) using a pedigreed synthetic population generated upon collecting broodstock from different fishery grounds in Egypt. The estimated heritabilities (h 2 ± SE) of survival from generations G0 to G3 ranged from 0.144 ± 0.026 to 0.008 ± 0.030 using a model that included the common environmental effect (c 2). Low heritability (0.014 ± 0.015) was estimated across generations with the inclusion of common environmental effect (c 2). However, the h 2 of survival from G0 to G1 ranged from 0.569 ± 0.071 to 0.410 ± 0.011 when c 2 was not included. The genetic correlation for survival between different ponds from G0 to G3 was moderate to high (0.79 ± 0.042 to 0.83 ± 0.012) but significantly different (P < 0.05). There were low correlation coefficients (−0.237 ± 0.089 to 0.316 ± 0.073) between body weight estimated breeding value (EBV) and survival EBV of families in four generations.

Genetic, nutritional and pathological investigations on the effect of feeding low protein diet and biofloc on growth performance, survival and disease prevention of Indian white shrimp Fenneropenaeus indicus

This experiment was carried out to investigate the effect of feeding low protein diets (~20BFd20.13; ~22BFd22.20; ~24BFd24.32, and ~26BFd26.44) in the presence of the biofloc on the growth performance and feed utilization of (Fenneropenaeus indicus) in comparison with commercial feed of 35% CP as control. The present study was based on application of genetic, nutritional and pathological tools. The biofloc was developed in the low protein diet using molasses as a carbon source. Fifty juveniles F. indicus with an average body weight of 0.52 ± 0.03 g were stocked in 50 L plastic tanks. Low protein diets and the control were tested in three replicates over a 112 days feeding trial. There were significant differences in protein, amino acids profile, lipids and fatty acids profile between the control and low diets group in the presence of the biofloc. However, less variation was noticed in the whole body composition (protein, amino acid profile, lipids and fatty acid profiles) of the shrimp between the control and low diets groups in the presence of the biofloc. There were no significant differences in final weight between control and low diets groups. Same trend was noted in the SGR, which did not vary significantly between low protein diets and control. However, the utilization of the biofloc by shrimp as a feed source was evident by the significant differences (P< 0.05) in FCR between low protein diets and control. There was a significant difference in the shrimp survival (%) (P< 0.05) between the low protein diets and the control which ranged between 86.66 % and 66.66 %, respectively. The development of biofloc significantly reduced the TAN, nitrate NO3-N and nitrite NO2-N levels in the low protein diets tanks. Diagnostic of mortality cases revealed that biofloc can serve as a biosecurity system for shrimp farmimg. RAPD-PCR were used to study the epidemiology of Vibrio parahaemolyticus responsible for early mortality syndrome (EMS) isolated from the water of culture system. The OPC5 (GATGACCGCC) primer produced bands ranged from 1 to 8 with sizes from 0.2–5.0 kb.

Physicochemical properties of anti Vibrio harveyi egg yolk antibody (IgY) and its immunological influence in Indian white shrimp Fenneropenaeus indicus

Edible antibodies specific to host pathogens is an attractive approach to establish protective immunity, especially against gastrointestinal pathogens both in humans and animals. The edible antibody of anti-Vibrio harveyi IgY (anti-V. h IgY) was produced by antigen mixed with immunoadjuvant Asparagus racemosus and Glycine max. Hens were immunized and eggs were collected five weeks after the immunization. Anti-V. harveyi IgY stability in different digestive enzymes such as trypsin and chymotrypsin were evaluated to determine its ability to withstand in the gastrointestinal tract of F. indicus. Specific binding activity and concentration (average 9.5% of total IgY content) of the anti-V. h IgY were determined by the ELISA using V. harveyi antigen. Further the anti-V. h IgY diets including V.h wo, V.h A, V.h G and control diets were fed to F. indicus for 60 days. After 30 and 60 of feeding, group of shrimps were challenged with virulent V. harveyi. After the respective days of feeding, haematological and immunological changes were studied. The parameters including total haemocyte count (THC), coagulase activity, oxyhaemocyanin level, prophenoloxidase, intracellular superoxide anion production, lysozyme, phagocytosis and bacterial agglutinin had significantly (P ≤ .001) increased in the experimental groups in comparission with the control diet fed shrimps. The anti-V. h IgY coated diets helped to reduce the Vibrio load and boosted the immune system in F. indicus's against V. harveyi challenge. The research work shows the potential applications of egg yolk antibodies as anti-bacterial prophylactic uses for infectious diseases and suggests an edible antibody concept as an alternative to conventional antibiotics.

Length-weight relationship and certain biological aspects of the Indian white shrimp Fenneropenaeus indicus (H. Milne Edwards, 1837) exploited by trawls in the Arabian Sea off Kerala coast, India

Length-weight relationship (LWR), sex ratio and maturity of Fenneropenaeus indicus (H. Milne Edwards, 1837), was analysed based on samplings from coastal trawl fishing grounds in the Arabian Sea off Kerala coast, India. The male tofemale ratio (1:1.27) did not vary significantly from the hypothetical 1:1 ratio. Length at maturity (Lm50) was estimated at 122 mm total length for females. The LWR did not differ significantly between male and female shrimps. The information generated from this study will enhance knowledge on the biology of the species and assist in assessment and management of its stock.

A study on β-glucan binding protein (β-GBP) and its involvement in phenoloxidase cascade in Indian white shrimp Fenneropenaeus indicus

The present study reports the purification of novel immune molecule β-1, 3 glucan binding protein from the heamolymph of the Indian white shrimp, Fenneropenaeus indicus (Fiβ-GBP). The purified Fiβ-GBP had 95kDa molecular weight in SDS-PAGE analysis. MALDI-TOF/TOF analysis revealed that the purified Fiβ-GBP showed similarity to various crustacean proteins; 48 and 46% similarity was observed for β-1, 3 glucan binding protein of Chinese white shrimp Fenneropenaeus chinensis and banana shrimp Fenneropenaeus merguiensis, with MOWSE score of 3.11e+12 and 2.05e+8, respectively. The phenoloxidase activity (PO) of Fiβ-GBP was evaluated and, in the presence of laminarin, PO activity increased significantly. Substrate specificity assay demonstrated that Fiβ-GBP had the specific binding site for soluble or insoluble β-glucan (laminarin), since the PO activity increased in the presence of laminarin when compared to other sugars. Enzymatic activities revealed that the optimum temperature and pH for Fiβ-GBP activating PO were 40°C and pH 7–8. Moreover, even at 100°C Fiβ-GBP enhanced PO activity highlighting that Fiβ-GBP was thermostable and thermophilic in nature. Among various divalent metallic ions, Fiβ-GBP significantly promoted the PO activity in presence of Mg2+ and Ca2+. The breakdown of para nitroanilide from Nα−Benzoyl-l-Arginine 4-Nitroanilide hydrochloride showed that serine protease activity was induced by Fiβ-GBP and also increased concentration of Fiβ-GBP evoked the activity. Furthermore, hemolytic activity tests revealed that PO reaction product induced RBC membrane damage and cell shrinkage. Lastly, Baclight bacterial viability assays showed maximum killing effect of PO reaction product on both Gram positive and Gram negative bacteria.

Shelf-Life of Indian White Shrimp Fenneropenaeus indicus Stored in Different Icing Conditions

The Shelf-life of farmed Indian white shrimp Fenneropenaeus indicus, formerly Penaeus indicus stored in ice using three different ratios of ice for 22 days was evaluated. During the storage period, changes in sensory characteristics, TMA-N levels, pH values and total bacterial count (TBC) were investigated, where the results showed a clear deterioration in the appearance, texture and odor of F. indicus from the 10th day in the samples stored at a shrimp to ice ratio of 1:1 and from the 12th day in the samples stored at a ratio of 1:2, while no such deterioration was observed in the samples stored at ratio of 1:3 until the 18th day of storage. The TMA-N levels increased with time during the icing storage. The TBC of the normal flora in the flesh of F. indicus increased with the time of storage. Changes in the sensory characteristics were associated with the changes in TMAN, pH and TBC, showing that the 1:2 ratio did not significantly extend the shrimp shelf-life compared to 1:1, whereas 1:3 significantly delayed the deterioration rate of quality, providing the longest shelf-life and the highest quality shrimp. The shelf-life extended to 9, 11 and 17 days at ratios of 1:1, 1:2 and 1:3 (shrimp to ice), respectively. Therefore, for storage purposes in ice, using a large amount of ice at a 1:3 ratio is recommended, as it extended the shelf-life to the greatest extent in this study.

Haemolytic and antibiofilm properties of haemocyanin purified from the haemolymph of Indian white shrimp Fenneropenaeus indicus

Haemocyanin (Hc) is an important non-specific immune macromolecule present in the haemolymph of both mollusks and crustaceans. In the present study, Hc was purified from the haemolymph of Indian white shrimp Fenneropenaeus indicus by gel filtration chromatography and it exhibits a single band with a molecular weight of 74 kDa on SDS-PAGE. The X-ray diffraction (XRD) and High performance liquid chromatography (HPLC) result of purified Hc express single peak at 31.5° be a sign of crystalline nature and appear as a single peak with a retention time of 5.6 min signify the homogeneity nature of the protein respectively. The purified Hc exhibited haemolytic activity against chicken erythrocytes. The haemolytic activity of purified Hc in optimum conditions observed to be pH 6.0, temperature 40 °C, in the presence of calcium. As well purified Hc exhibited the antibiofilm activity against both Gram positive and Gram negative bacteria. Moreover, the haemolysis can be inhibited to different degrees by osmoprotectants of diverse molecular masses, signifying that it follows a colloid-osmotic mechanism. This study conclude that purified Hc from F. indicus remarkably possess haemolytic and antibiofilm activity.

Effect of Vacuum Packaging and Sous Vide Processing on the Quality of Indian White Shrimp (Fenneropenaeus indicus) During Chilled Storage

ABSTRACTA comparative study was undertaken to assess the effect of sous vide (SV) processing, vacuum, and ordinary air packaging on the quality and shelf life of condiment-incorporated Indian white shrimp (Fenneropenaeus indicus) during chilled storage. The pasteurization value (PV) for SV-processed shrimp was 4.02 min at 90ºC. The initial K value of shrimp (2.17%) increased to 5.26% with SV processing and further increased to a value of 46.9% on the day of sensory rejection, compared with 64.3% and 62.7% for vacuum and air-packed samples, respectively. A nearly 3 log reduction in total mesophilic count was observed for SV-processed shrimp. Formation of volatile bases, indole, and lipid oxidation was significantly (p < 0.05) inhibited in SV-processed shrimp compared to others. SV processing extended the shelf life of condiment-incorporated shrimp up to 28 days, compared to only 15 and 8 days for vacuum and air-packed samples, respectively.

Development of ready to drink calcium fortified shrimp soup in retortable pouches

The aim of the study was to develop ready to serve calcium fortified shrimp soup in retortable pouches. Shrimp soup was prepared from Indian white shrimp ( Fenneropenaeus indicus ) and thermal processed at 121, 115 and 110OC to an F0 value of 6. The calcium fortified soup was then compared with control samples. The effect of different process temperatures on quality was analysed. The samples processed at 110OC showed significantly higher (p≤0.05) cook value and 121.1 O C showed the least. All the pouches were found to be commercially sterile. The viscosity of soup was significantly higher (p≤0.05) in control packs compared to fortified soups. Significantly higher (p≤0.05) b* value was observed in fortified soup compared to control. Thermally processed calcium fortified shrimp soup was in acceptable condition during the storage period of 90 days at ambient temperature without any significant change in calcium content. Sensorily, the product processed at 121OC rated better compared to 115 and 110 O C.

In vitro and in silico studies on cell adhesion protein peroxinectin from Fenneropenaeus indicus and screening of heme blockers against activity.

In invertebrates, the prophenoloxidase (proPO) pathway is involved in the phenol-like antioxidant production against invading pathogens. Overproduction of melanin and phenolic substances leads to the disruption of hemocytes (own host cells); therefore, there is a prerequisite to regulate the antioxidant production, which is performed by the proteases and proPO-associated cell adhesion protein peroxinectin (PX). PX is a macromolecular structure consisting of protein involved in the proPO pathway, which is a potential target in the regulatory mechanism in crustaceans. In the proPO cascade, pattern recognition proteins initiate the proPO cascade by the consequent reaction, and PX is involved in the key step in the regulatory mechanism of phenoloxidase enzyme synthesis. In the present study, Indian white shrimp Fenneropenaeus indicus PX (Fein-PX) gene sequence was used. Upregulation of Fein-PX was determined using immunostimulants β-glucan (agonists) and examined its expression by quantitative RT-PCR. To find the downregulation or negative regulation of Fein-PX, inhibitors were screened, and its 3D model provides molecular insights into the rationale inhibitor design for developing an effective molecule against Fein-PX.

Influence of Cyperus rotundus Active Principles Inhibit Viral Multiplication and Stimulate Immune System in Indian White Shrimp Fenneropenaeus indicus against White Spot Syndrome Virus Infection

Five herbs including Adathoda vasica, Agathi grandiflora, Leucas aspera, Psoralea corylifolia, and Quercus infectoria were selected to screen the antiviral and immunostimulant activity against white spot syndrome virus (WSSV) and Vibrio harveyi respectively using different organic polar and non-polar solvents. Based on the initial screening results, ethyl acetate and methanolic extracts of A. grandiflora had strong antiviral and immunostimulant activities. Those extracts incubated with WSSV injected Fenneropenaeus indicus got only 20% mortality and no PCR positive signals were seen in two step PCR amplification. The methanolic extracts of A. grandiflora were further purified through silica column chromatography and the fractions screened again for antiviral and immunostimulant activity. The secondary screening results revealed that, the fractions of F5 to F7 had effectively controlled the WSSV multiplication and V. harveyi growth. The pooled fractions (F5 to F7) was structurally characterized by gas chromatograph-mass spectrometry (GC-MS) analysis and few compounds were identified including 3,7.11,15-Tetramethyl-2Hexane-1-ol, pytol and 1,2-Benzenedicarboxylic acid, diisooctyl ester. The pooled fractions were mixed with the basal feed ingredients at the concentration of 100 (D-1), 200 (D-2), 300 (D-3) and 400 (D-4) mg kg � 1 and the diets fed to the F. indicus (9.0 ± 0.5 g) for 30 days. After the completion of feeding trail,

Dietary Supplementation of Dunaliella Salina on Growth Performance and Body Composition of Indian White Shrimp Fenneropenaeus Indicus (H Milne Edwards)

Juveniles of white shrimp, Fenneropenaeus indicus were fed with a micro green alga, Dunaliella salina through a fishmeal based supplementary diet containing 35% protein for a period of 180 days in fiberglass tanks. There were control and treatments for the study and both were triplicated. D. salina was incorporated at 0.5, 1.0, 2.0, 4.0 and 8.0% in the diet and was designated as treatments T1, T2, T3, T4 and T5 respectively. D. salina free diet was considered as Control. The diet containing D. salina at 2.0% (T3) showed significantly (p < 0.05) superior growth when compared to control and other treatments. Protein efficiency ratio and protein digestibility were found to be high in T3 and feed conversion efficiency was reduced. Better colour and taste were observed in D. salina fed shrimp compared to control. Crude protein, lipid, ash and nitrogen free extract (NFE) of the carcass did not show significant difference between control and treatments. Dietary administration of D. salina enhances growth and body colour in white shrimp F. indicus.

Influence of Agathi grandiflora active principles inhibit viral multiplication and stimulate immune system in Indian white shrimp Fenneropenaeus indicus against white spot syndrome virus infection

Five herbs including Adathoda vasica, Agathi grandiflora, Leucas aspera, Psoralea corylifolia, and Quercus infectoria were selected to screen the antiviral and immunostimulant activity against white spot syndrome virus (WSSV) and Vibrio harveyi respectively using different organic polar and non-polar solvents. Based on the initial screening results, ethyl acetate and methanolic extracts of A. grandiflora had strong antiviral and immunostimulant activities. Those extracts incubated with WSSV injected Fenneropenaeus indicus got only 20% mortality and no PCR positive signals were seen in two step PCR amplification. The methanolic extracts of A. grandiflora were further purified through silica column chromatography and the fractions screened again for antiviral and immunostimulant activity. The secondary screening results revealed that, the fractions of F5 to F7 had effectively controlled the WSSV multiplication and V. harveyi growth. The pooled fractions (F5 to F7) was structurally characterized by gas chromatograph-mass spectrometry (GC-MS) analysis and few compounds were identified including 3,7.11,15-Tetramethyl-2-Hexane-1-ol, pytol and 1,2-Benzenedicarboxylic acid, diisooctyl ester. The pooled fractions were mixed with the basal feed ingredients at the concentration of 100 (D-1), 200 (D-2), 300 (D-3) and 400 (D-4) mg kg−1 and the diets fed to the F. indicus (9.0 ± 0.5 g) for 30 days. After the completion of feeding trail, they were challenged with virulent WSSV and studied the cumulative mortality, molecular diagnosis by quantitative real time PCR (qRT-PCR), biochemical, haematological and immunological parameters. The control diet fed F. indicus succumbed to death 100% within 3 days whereas the D-3 and D-4 helped to reduced the cumulative mortality of 60–80% respectively. The qRT-PCR revealed that, the WSSV copy number was gradually decreased when increasing concentration of A. grandiflora extract active fraction in the diets. The diets D-3 and D-4 helped to reduce the protein and carbohydrate levels significantly (P < 0.01) from the control diet fed groups. Moreover these diets help to decrease the coagulation time of maximum 61% from control groups and improve the total haemocyte count of maximum 51.82 × 105 cells ml−1 in D4 diet fed F. indicus. Finally immunological parameters including prophenol oxidase (proPO) activity, intracellular superoxide anion production and intra-agar lysozyme activity was significantly (P ≤ 0.001) improved in the D-3 and D-4 fed F. indicus after WSSV challenge.

Molecular cloning of peroxinectin gene and its expression in response to peptidoglycan and Vibrio harveyi in Indian white shrimp Fenneropenaeus indicus.

The cDNA sequence of peroxinectin was obtained from the haemocytes of Indian white shrimp Fenneropenaeus indicus using RT-PCR and RACE. Fenneropenaeus indicus peroxinectin (Fi-Pxn) sequence has an open reading frame (ORF) of 2415 bp encoding a protein of 804 amino acids with 21 residues signal sequence. The mature protein has molecular mass of 89.8 kDa with an estimated pI of 8.6. Two putative integrin-binding motifs, RGD and KGD, were observed at the basic N-terminal and C-terminal part of the mature aminoacid sequence. Fi-Pxn nucleotide sequence comparison showed high homology to mud crab Scylla serrata (89%) and to various vertebrate and invertebrate species. qRT-PCR showed peroxinectin mRNA transcript in haemocytes of F. indicus increased at 6 h post injection of peptidoglycan and Vibrio harveyi. The Fi-Pxn was mainly expressed in the tissues of haemocytes and the heart. The moulting stage responses showed Fi-Pxn expression in premoult stages D0/1 and D0/2.