Physicochemical properties of cricket(Gryllus bimaculatus)gel fraction with soy protein isolate for 3D printing-based meat analogue

Cricket(Gryllus bimaculatus)gel was fractionated and mixed with different soybean protein isolate(SPI)con-centrations,and its characteristics were evaluated to determine its potential use as a meat analog.Crushed crickets were separated into the filtrate,supernatant,and pellet fractions by centrifugation and freeze-drying,and powdered and mixed with 18%SPI at different concentrations(5%-20%).The filtrate fraction had the lowest protein content and the highest fat and carbohydrate content among the nutrient fractions.Conversely,the supernatant and pellet fractions had high protein,low fat,and low carbohydrate content.SDS-PAGE detected relatively low-molecular weight proteins.Numerous muscle proteins were identified,including actin,myosin,and hemocyanin,a protein that transports oxygen in insects.Regarding the rheological characteristics of the cricket fraction,the entire fraction exhibited G’>G"in both the frequency and the temperature sweep tests,revealing a tendency for gel-like viscosity.In all cricket fractions,both G’and G"increased with increasing fraction powder concentration.When printed,supernatant fractions had no structural stability,pellet fractions had 5%-15%stability,and filtrate fractions had 5%-20%stability.The three interval thixotropy test revealed that the pellet fraction had a recovery rate of over 90%after high shear deformation.Texture profile analysis showed an increase in both hardness and chewability.After heat treatment,cohesiveness was higher than adhesiveness,indicating greater elasticity.Field-emission scanning electron microscopy results revealed that the pellet fraction was denser than the other fractions,particularly at higher concentrations.Based on the overall characteristics,15%pellets were found to be the most appropriate fraction and concentration.

Conservation aquaculture of Ompok bimaculatus (Butter catfish), a near threatened catfish in India

The butter catfish,Ompok bimaculatus,belonging to the silurid family,is widely regarded as an important food fish for aquaculture diversification in India.Furthermore,the species poses a threat due to habitat degradation and other anthropogenic factors,and has been categorised as“near threatened”,therefore,its culture promotion is warranted.To establish a successful breeding programme,a precise understanding of the life history,and biology(reproductive/feeding)of the fish will assist hatchery managers and researchers.Studies in these areas have been undertaken by several groups over the years,but without much coherence,the data are still fragmented.Few attempts on the culture attributes of this catfish have been performed under both mono-and polyculture systems to bring about parallel promotion through aquaculture in a larger part of the subcontinent.Highlighting this,we have tried to analyse and present a consolidated account of the morphological characteristics,feeding habits,reproductive biology,early developmental ontogeny,and culture potentials of O.bimaculatus in India.This review was also prompted by the paucity of information on the cultural aspects of the species.Additionally,based on the reported studies,future directions and perspectives of the culture promotion of the species are proffered to ensure future research initiatives.

Screening and validation of reference genes for qPCR analysis in gonads and embryos of Takifugu bimaculatus

Suitable reference genes are one of the necessary conditions for obtaining reliable results by real-time fluorescence quantitative PCR(qPCR).In this study,the expression of the 10 common candidate reference genes(18s rRNA,rps27,cnbp,rpl7,ube2,hsp-at,gapdh,β-actin,rpl13a,1-ef1a)at different developmental stages of gonad and embryo of Takifugu bimaculatus were analyzed by qPCR.And the expression stability of these reference genes is analyzed by GeNorm,NormFinder and Bestkeeper softwares.The results showed that the expression stability of 1-ef1a was the highest(p<0.05)combined with the results of three analysis softwares,and the optimal number of reference genes was 3,which were 1-ef1a,hsp-at and rps27.Based on this result,we analyzed the expression of objective genes(foxl2 and dmrt1)at different developmental stages(early,medium-term and late)of gonads and embryos(eye vesicle stage,motility stage,heart anlage stage,retinal pigmentation stage,newly hatched larva)of T.bimaculatus by qPCR.Among which the highest expression level of foxl2 was in the middle stage of ovary(p<0.05),and dmrt1 was expressed in the early stage of testis with the highest level(p<0.05).The expression levels of foxl2 and dmrt1 in the early stages of embryonic development were low or even almost non-existent,and had a slight increase in the late embryonic development(newly hatched larva).The expression profile of objective genes are consistent with their roles in the development of gonads and embryos,which indicates that 1-ef1a,hsp-at and rps27 are the suitable reference gene combination for detecting the expression of objective genes by qPCR in gonads and embryos of T.bimaculatus.This research also provides the reliability data for screening the reference genes by qPCR in fish.