scholarly journals Molecular approach for insect detection in feed and food: the case of Gryllodes sigillatus

2020 ◽  
Vol 246 (12) ◽  
pp. 2373-2381
Author(s):  
Enrico Daniso ◽  
Francesca Tulli ◽  
Gloriana Cardinaletti ◽  
Roberto Cerri ◽  
Emilio Tibaldi

AbstractThe production of insects on an industrial scale has attracted the attention of the research and agricultural industry as novel protein sources. To detect the presence of Gryllodes sigillatus (GS) in feed and food, a real-time PCR method based on the mitochondrial cytochrome b (CYB) gene is proposed by this study. Forty DNA samples of animal and plant origin were used to confirm the specificity of the qPCR system. The detection method’s performance was evaluated on different processed GS matrices including native GS (UnGS) and different commercial products: crunchy roasted samples (RoGS), insect meal mixtures (ACGS) and energetic snacks containing GS (GSS). Data on sequencing were aligned with the reference gene to confirm the PCR products. The regression curve (y = −3.394 x + 42.521; R2 = 0.994, d.f. 14) between Ct values and Log DNA concentrations of Gryllodes sigillatus resulted in an efficiency of 96.4%. The severity of the technological processing treatments and the matrix structure affected the intensity of the PCR signal with the same amount of insect DNA as observed by different y-intercepts of the three-regression lines for RoGS, ACGS, and GSS. The real-time PCR method resulted in robust and sensitive outcomes able to detect low amounts of GS DNA (5 g/100 g) in a complex matrix, making it suitable for detecting the presence or absence of labeled Gryllodes sigillatus material both in feed and food.

2020 ◽  
Vol 18 ◽  
Author(s):  
Pegah Shakib ◽  
Mohammad Reza Zolfaghari

Background: Conventional laboratory culture-based methods for diagnosis of Streptococcus pneumoniae are time-consuming and yield false negative results. Molecular methods including real-time (RT)-PCR rapid methods and conventional PCR due to higher sensitivity and accuracy have been replaced instead traditional culture assay. The aim of the current study was to evaluate lytA gene for detection of Streptococcus pneumoniae in the cerebrospinal fluid of human patients with meningitis using real-time PCR assay. Material and Methods: In this cross-sectional study, a total of 30 clinical specimens were collected from patients in a period from September to December 2018. In order to evaluate the presence of lytA gene, conventional and real-time PCR methods were used without culture. Results: From 30 sputum samples five (16.66%) isolates were identified as S. pneumoniae by lytA PCR and sequencing. Discussion: In this research, an accurate and rapid real-time PCR method was used, which is based on lytA gene for diagnosis of bacteria so that it can be diagnosed. Based on the sequencing results, the sensitivity for detection of lytA gene was 100% (5/5).


2003 ◽  
Vol 69 (12) ◽  
pp. 7430-7434 ◽  
Author(s):  
Trevor G. Phister ◽  
David A. Mills

ABSTRACT Traditional methods to detect the spoilage yeast Dekkera bruxellensis from wine involve lengthy enrichments. To overcome this difficulty, we developed a quantitative real-time PCR method to directly detect and enumerate D. bruxellensis in wine. Specific PCR primers to D. bruxellensis were designed to the 26S rRNA gene, and nontarget yeast and bacteria common to the winery environment were not amplified. The assay was linear over a range of cell concentrations (6 log units) and could detect as little as 1 cell per ml in wine. The addition of large amounts of nontarget yeasts did not impact the efficiency of the assay. This method will be helpful to identify possible routes of D. bruxellensis infection in winery environments. Moreover, the time involved in performing the assay (3 h) should enable winemakers to more quickly make wine processing decisions in order to reduce the threat of spoilage by D. bruxellensis.


2013 ◽  
Vol 46 (15) ◽  
pp. 1566-1571 ◽  
Author(s):  
Weidong Zheng ◽  
Yuwei Di ◽  
Yinghong Liu ◽  
Ge Huang ◽  
Youwei Zheng ◽  
...  

2013 ◽  
Vol 12 (3) ◽  
pp. 107-113 ◽  
Author(s):  
Jie Huang ◽  
Chun Gao ◽  
Xilai Ding ◽  
Shoufang Qu ◽  
Licheng Liu ◽  
...  

2015 ◽  
Vol 159 ◽  
pp. 5-12 ◽  
Author(s):  
P. Gyawali ◽  
J.P.S. Sidhu ◽  
W. Ahmed ◽  
P. Jagals ◽  
S. Toze

2009 ◽  
Vol 11 ◽  
pp. S106-S108 ◽  
Author(s):  
Tomoharu Tokutomi ◽  
Yuzo Takada ◽  
Takako Murayama ◽  
Masahiro Mukaida ◽  
Jun Kanetake

Author(s):  
Aymen Abdelhaleem ◽  
Nabil Dhayhi ◽  
Mohamed Salih Mahfouz ◽  
Ommer Daffalla ◽  
Mansour Mubarki ◽  
...  

Visceral leishmaniasis (VL) is the most severe clinical form of the disease and has been reported in the Jazan region of southwest Saudi Arabia. This study aimed to diagnose VL by real-time polymerase chain reaction (PCR) and the direct agglutination test (DAT) and to identify the causative Leishmania species. A total of 80 participants, including 30 suspected VL patients, 30 healthy endemic control individuals, and 20 malaria disease controls, were enrolled in this study. Blood samples were collected and tested for Leishmania DNA by real-time PCR and for antibody by the DAT. Sequencing of some amplified PCR products was used to identify the causative Leishmania species. The diagnosis of VL was successfully achieved by both real-time PCR and by DAT with 100% sensitivity. Leishmania donovani and Leishmania infantum species were detected by sequencing both by the kDNA and ITS1 target genes, followed a BLASTn search. The detection of VL antibody by the DAT followed by the confirmatory detection of Leishmania DNA in patient blood by PCR could promote the adoption of the much less invasive and more sensitive methods for the routine diagnosis of VL. Further study with high sample volume to evaluate the PCR and the DAT are needed, to generate more robust evidence. Based on the sequencing results, emerging studies on VL should focus on the causative Leishmania species, reservoirs, and vectors that are important in the study area.


2015 ◽  
Vol 35 (3) ◽  
pp. 306-313 ◽  
Author(s):  
Abdullah Kilic ◽  
Mohammad J. Alam ◽  
Naradah L. Tisdel ◽  
Dhara N. Shah ◽  
Mehmet Yapar ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document