The Potential Role of Plastome Copy Number as a Quality Biomarker for Plant Products using Real-time Quantitative Polymerase Chain Reaction.

Background: Plastids are plant-specific semi-autonomous self-replicating organelles, containing circular DNA molecules called plastomes. Plastids perform crucial functions, including photosynthesis, stress perception and response, synthesis of metabolites, and storage. The plastome and plastid numbers have been shown to be modulated by developmental stage and environmental stimuli and have been used as a biomarker (identification of plant species) and biosensor (an indicator of abiotic and biotic stresses). However, the determination of plastome sequence and plastid number is a laborious process requiring sophisticated equipment. Methods: This study proposes using plastome copy number (PCN), which can be determined rapidly by real-time quantitative polymerase chain reaction (RT-qPCR) as a plant product quality biomarker. This study shows that the PCN log10 and range PCN log10 values calculated from RT-qPCR data, which was obtained for two years from leaves and lint samples of cotton and seed samples of cotton, rice, soybean, maize, and sesame can be used for assessing the quality of the samples. Results: Observation of lower range PCN log10 values for CS (0.31) and CR (0.58) indicated that the PCN showed little variance from the mean PCN log10 values for CS (3.81) and CR (3.85), suggesting that these samples might have encountered ambient environmental conditions during growth and/ or post-harvest storage and processing. This conclusion was further supported by observation of higher range PCN log10 values for RS (3.09) versus RP (0.05), where rice seeds in the RP group had protective hull covering compared to broken hull-less seeds in the RS group. To further support that PCN is affected by external factors, rice seeds treated with high temperatures and pathogens exhibited lower PCN values when compared to untreated seeds. Furthermore, the range PCN log10 values were found to be high for cotton leaf (CL) and lint (Clt) sample groups, 4.11 and 3.63, respectively, where leaf and lint samples were of different sizes, indicating that leaf samples might be of different developmental stage and lint samples might have been processed differently, supporting that the PCN is affected by both internal and external factors, respectively. Moreover, PCN log10 values were found to be plant specific, with oil containing seeds such as SeS (6.49) and MS (5.05) exhibiting high PCN log10 values compared to non-oil seeds such as SS (1.96). Conclusion: In conclusion, it was observed that PCN log10 values calculated from RT-qPCR assays were specific to plant species and the range of PCN log10 values can be directly correlated to the internal and external factors and, therefore might be used as a potential biomarker for assessing the quality of plant products.

Enhancing Cohort PASA Efficiency from Lessons Assimilated by Mutant Genotyping in C. elegans.

Classical restriction fragment length polymorphism (RFLP) and sequencing are labor-intensive and expensive methods to study single base changes, whereas polymerase chain reaction amplification of specific alleles (PASA) or allele-specific polymerase chain reaction (ASPCR) is a PCR-based application that allows direct detection of any point mutation by analyzing the PCR products in an ethidium bromide-stained agarose or polyacrylamide gel. PASA is based on oligonucleotide primers containing one or more 3' mismatch with the target DNA making it refractory to primer extension by Thermus aquaticus DNA polymerase lacking the 3' to 5' exonuclease proofreading activity because of which it is also called amplification refractory mutation system-PCR (ARMS-PCR). This technique has found application in detection of allele, mutation, single-nucleotide polymorphisms (SNPs) causing genetic and infectious diseases. This chapter describes an approach of cohort PASA in context of genotyping single and double mutant worms generated to study the process of cell migration and axon outgrowth in C. elegans. Single worm-based cohort PASA allows genotyping for identification of single base mutations; particularly it is convenient method to detect mutations without a visible phenotype.

A-90 Day Gavage Safety Assessment of Boswellia serrata in Rats.

The present study deals with the evaluation and assessment of the safety/toxic potential of Boswellia serrata, a well known Ayurvedic herb used to treat disorders of digestive system, respiratory ailments and bone related diseases. A repeated dose oral (90 days) toxicity study of Boswellia serrata was carried out. For this, 10 rats of each sex were treated with the Boswellia serrata at three different doses i.e. 100, 500 and 1000 mg/kg B. wt. /day. As a control, 10 rats of each sex were treated with corn oil only which was the vehicle. Two groups consisting of five male and five female rats were kept as control recovery and high dose recovery group which were treated with the vehicle (corn oil) and the Boswellia serrata at the dose of 1000 mg/kg B. wt. Animals of control recovery and high dose recovery groups were further observed for 28 days without any treatment. From this study, it was found that the rats treated with high dose of the Boswellia serrata gained their body weight with much less rate than that of the control group. However, during the recovery period, the loss in body weight gain as observed during the study period exhibits a reversible effect on the metabolic activity and recovered. The results also indicate that Boswellia serrata is relatively safe in rat up to the dose of 500 mg/kg B.wt. as no adverse impact on health factors was observed. Thus, the No observed adverse effect level is 500 mg/kg B. wt.