Exploring Marine as a Rich Source of Bioactive Peptides: Challenges and Opportunities from Marine Pharmacology

This review highlights the underexplored potential and promises of marine bioactive peptides (MBPs) with unique structural, physicochemical, and biological activities to fight against the current and future human pathologies. A particular focus is given to the marine environment as a significant source to obtain or extract high-value MBPs from touched/untouched sources. For instance, marine microorganisms, including microalgae, bacteria, fungi, and marine polysaccharides, are considered prolific sources of amino acids at large, and peptides/polypeptides in particular, with fundamental structural sequence and functional entities of a carboxyl group, amine, hydrogen, and a variety of R groups. Thus, MBPs with tunable features, both structural and functional entities, along with bioactive traits of clinical and therapeutic value, are of ultimate interest to reinforce biomedical settings in the 21st century. On the other front, as the largest biome globally, the marine biome is the so-called “epitome of untouched or underexploited natural resources” and a considerable source with significant potentialities. Therefore, considering their biological and biomedical importance, researchers around the globe are redirecting and/or regaining their interests in valorizing the marine biome-based MBPs. This review focuses on the widespread bioactivities of MBPs, FDA-approved MBPs in the market, sustainable development goals (SDGs), and legislation to valorize marine biome to underlying the impact role of bioactive elements with the related pathways. Finally, a detailed overview of current challenges, conclusions, and future perspectives is also given to satisfy the stimulating demands of the pharmaceutical sector of the modern world.     

Single-marker and haplotype-based association analysis of anthracnose (Colletotrichum dematium) resistance in spinach (Spinacia oleracea)

Anthracnose (Colletotrichum dematium) is an important disease in spinach (Spinacia oleracea). Sources of resistance must be identified, and molecular tools must be developed to expedite cultivar development. In this study, a diverse collection of 276 spinach accessions was scored for anthracnose disease severity. We then evaluated marker identification approaches by testing how well haplotype-based trait modelling compares to single markers in identifying strong association signals. Alleles in linkage disequilibrium were tagged in haplotype blocks, and anthracnose-associated molecular markers were identified using single-SNP (sSNP), pairwise haplotype (htP) and multi-marker haplotype (htM) SNP tagging approaches. We identified 49 significantly associated markers distributed on several spinach chromosomes using all methods. The sSNP approach identified 13 markers, while htP identified 24 (~63% more) and htM 34 (~162% more). Of these markers, four were uniquely identified by the sSNP approach, nine by htP and nineteen by htM. The results indicate that resistance to anthracnose is polygenic and that haplotype-based analysis may have more power than sSNP. Using a combination of these methods can improve the identification of molecular markers for spinach breeding.     

Participatory plant breeding in maize: A case study from Gujarat, India

This paper describes how plant breeders and farmers worked together to produce improved varieties of maize for the low-resource farmers of the Panchmahals district of Gujarat, India. Initially, farmers tested a range of maize varieties in a participatory varietal selection (PVS) programme. However, none of these proved to be very popular with farmers, although farmers who had more fertile fields adopted the variety Shweta from Uttar Pradesh. Hence, in 1994 a participatory plant breeding (PPB)programme was begun to generate new, more appropriate varieties. Yellow- and white-endospermed maize varieties were crossed that had been either adopted to some extent following PVS or had attributes, such as very early maturity,that farmers had said were desirable. In subsequent generations, the population was improved by mass selection for traits identified by farmers. In some generations,farmers did this in populations which were grown by breeders on land rented from a farmer. Soil fertility management was lower than that normally used on the research-station. The breeding programme produced several varieties that have performed well in research-station and on-farm trials. One of them, GDRM-187, has been officially released as GM-6 for cultivation in hill areas of Gujarat state,India. It yielded 18% more than the local control in research-station trials, while being seven days earlier to silk. In farmers' fields, where average yields were lower, the yield advantage was 28% and farmers perceived GDRM-187 to have better grain quality than local landraces. PPB produced a variety that was earlier to mature than any of those produced by conventional maize breeding, and took fewer years to do so. The returns from PPB,compared to conventional breeding, are higher because it is cheaper and benefits to farmers are realised earlier. This revised version was published online in August 2006 with corrections to the Cover Date.     

Challenges to wheat production in South Asia

Wheat is the second major staple crop, after rice, in India and Pakistan and is also gaining similar importance in Nepal and Bangladesh. Wheat production in South Asia has increased from 15 mt in 1960s to 95.5 mt during 2004–2005. It still needs to grow at the rate of 2–2.5% annually until the middle of 21st century. However, for India, recent estimations have shown a growth requirement of about 1.1%. Although the wheat improvement programs in these countries, with the active collaboration of national agricultural research centers (NARS) and CIMMYT, has made a significant progress, it is a matter of significant concern that wheat production has stagnated for last few years. Since there is little scope for increasing land area under wheat, the major challenge will be to break the yield barrier by pragmatic genetic and developmental approaches. The most serious constraints to wheat production in this region are a host of biotic and abiotic stresses. Although India has not faced any rust epidemic in the last decade, rusts continue to occupy the place of most dangerous pathogen for the region. Among the abiotic stresses, unusual warming trends during grain filling period are causing yield declines, especially in eastern and central India. There are other challenges that are specific to the highly productive rice–wheat cropping system predominant in the Indo-Gangetic plains. The total factor productivity of this system is declining due to depletion of soil organic carbon. Addition of organic matter to soil through green manuring and crop residue recycling, balanced fertilization, integrated nutrient management, diversification of rice-wheat system are some of the possible remedial measures to improve total factor productivity. The international linkages with CIMMYT needs to be strengthened more closely for developing more productive wheat genotypes and thus, achieving wheat targets in the South Asian region.     

Variation and inheritance of leaf angle, and its association with spot blotch (Bipolaris sorokiniana) severity in wheat (Triticum aestivum)

One thousand four hundred and seven spring wheat germplasm lines belonging to Indian and CIMMYT wheat programs were evaluated for their leaf angle and resistance to spot blotch caused by Bipolaris sorokiniana during three consecutive crop seasons, 1994–95, 1995–96 and 1996–97.Disease severity was recorded at six different growth stages beginning from tillering to late milk stage. Three crosses (M 3109 × Sonalika, HP 1808 × K 9006 and HD 2662 × K 9006) were made between genotypes with erect and drooping leaves. M 3109 was resistant, Sonalika susceptible while the other three lines possessed moderate resistance to spot blotch. Individually threshed F₂ plants were used to advance the generations. Leaf angle and spot blotch resistance were recorded in parents, F₁, F₃, F₄and F₅ generations. Leaf erectness in F₁ generation showed partial dominance. Evaluation of F₃, F₄ and F₅ progenies(120–150) revealed that leaf angle was under the control of few genes that appeared to be close to three. Germplasm lines with erect and semi-erect leaves displayed lower spot blotch severity than those having drooping and semi-drooping leaves. Lines homozygous for erect leaf posture in F₃,F₄ and F₅ generations showed significantly lower mean AUDPC than those with drooping leaves. A positive correlation (0.58) between leaf angle and AUDPC further indicated a positive influence of leaf erectness on severity to spot blotch disease. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effect of isolated fractions of Barleria prionitis root methanolic extract on reproductive function of male rats: preliminary study

Male rats treated with 100 mg/kg for 60 days of isolated fractions of the Barleria prionitis root methanolic extract (Fr. I and Fr. II) showed a significant reduction on spermatogenesis without affecting general body metabolism. Sperm motility as well density in cauda epididymides was reduced significantly. The fertility was decreased by 33.4% in Fr. I and 100% in Fr. II treated rats. The blood parameters were within the normal range. Total protein, glycogen and sialic acid contents of testes were reduced after the plant fractions treatment. Seminal vesicular fructose was decreased significantly after the treatment. The population of various spermatogenic cells such as primary spermatocytes, secondary spermatocytes and round spermatids were declined significantly in Fr. II treatment groups whereas in Fr. I treated animals preleptotene spermatocyte and spermatid number was decreased. There was no significant change in the number of Sertoli cells and spermatogonia in any of the treatment group.     

POSS/polypropylene hybrid nanocomposite monofilaments by reactive extrusion

The Allyl-heptaisobutyl-polyhedral oligomeric silsesquioxane (AHO-POSS) grafted polypropylene (PP) was prepared by reactive extrusion and by physical blending routes. The structure and properties of physically blended and reactively blended POSS/PP nanocomposites were investigated by FTIR, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermogravimetric analysis, SEM, spherutlic growth and mechanical properties studies. Chemical bonding of POSS with PP in reactive extrusion was confirmed by FT-IR spectroscopy. DSC and TGA studies showed that the thermal stability of AHO-POSS/PP nanocomposite prepared by reactive extrusion improved significantly as compared to only physically blended nanocomposites. WAXD studies showed decrease in crystallinity of the AHO-POSS/PP nanocomposites prepared by reactive extrusion. SEM studies showed aggregation tendency in case of physically blended AHO-POSS/PP nanocomposites. Spherulite growth studies show reactive blending retards spherulite growth in PP polymer.     

Potentiality of Potato Flour as Humectants (Anti-staling Agent) in Bakery Product: Muffin

The potential of potato flour as a humectant (anti-staling agent) was investigated. The experiment utilised eight variants of potato flour, prepared from processing cultivar K. Chipsona-1 and table cultivar K. Laukar, in muffins as a bakery product. On the basis of higher values of water retention and water absorption, and comparatively lower values of setback and flavour intensity, grilled (180 W for 25 min) potato flour from cultivar K. Laukar (GPF-T) was selected for muffin preparation. For optimization, muffins were prepared with GPF-T at 1, 3, 5 and 7% (w/w) level in the formulation. The storage study was conducted for 8 days at 25?±?2 °C and 55?±?5% RH. It was concluded from the product characterisation, sensory evaluation and storage study that 3% GPF-T can be used as a low-cost alternative to commercially available humectants for muffin preparation. Research findings may be adopted by small-scale industry entrepreneurs to delay the staling of muffins two-fold without adversely affecting the sensory scores.     

Wheat somaclonal variants showing earliness, improved spot blotch resistance and higher yield

Somaclones (R₂, R₃ and R₄generations) were regenerated from immature embryos of two spring wheat varieties,HUW-206 and HUW-234. Many somaclones displayed improved earliness, enhanced resistance to spot blotch disease and increased yield over the parent. The superiority of variants for yield traits and disease resistance was established in R₄ generation, confirming the possibility of wheat improvement through somaclonal variation. This revised version was published online in July 2006 with corrections to the Cover Date.     

Potential suitable habitat of Buckwheat (Fagopyrum spp) under the climate change scenarios in Nepal

Journal of Crop Science and Biotechnology - Buckwheat is minor crop of Nepal. Due to their multiple uses, short growing periods, high nutritional and medicinal values, wide adaptability has become...