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Microalgal research has made significant progress due to versatile and high‐value industrial applications of microalgal biomass or its derivatives. However, to explore their full potential and to achieve commercial robustness, microalgal biorefinery needs cost‐effective technologies to produce, harvest, and process the microalgal biomass on large scale as higher production and harvesting cost is one of the key hindrances in the commercialization of algae‐based products. Among several other algal biomass harvesting technologies, self‐flocculation seems to be an attractive, low‐cost, and eco‐friendly harvesting technology. This review covers various flocculation‐based methods that have been employed to harvest microalgal biomass with a special emphasis on self‐flocculation in microalgae. Moreover, genetic engineering approaches to induce self‐flocculation in non‐flocculating microalgae along with the factors affecting self‐flocculation and recent research trends have also been discussed. It is concluded that self‐flocculation is the most desired approach for the energy‐ and environment‐efficient harvesting of microalgal biomass. However, its poorly understood genetic basis needs to be deciphered through detailed studies to harness its potential for the algal biorefinery. [ABSTRACT FROM AUTHOR]

The main objective of the present study was evaluation of genotypic potential among four sorghum genotypes through the analysis of different growth and nutrients uptake in salt stress. The four sorghum genotypes, JS-2002, Sandalbar, Noor and FJ-115 were utilized in the experiments to study the mechanism of salt tolerance using 0 or 100 mM NaCl stress. The analysis was carried out on growth and different ion concentrations e.g., sodium, potassium, calcium and chlorides of both shoots and roots. The differences among means were calculated and analysis of variance technique was used for comparison of salt tolerance between cultivars. Results showed that salinity adversely affected growth of all four sorghum genotypes. The fresh weight of plants was reduced by salt stress in sorghum. The uptake of toxic compounds was increased in the presence of salt stress as compared with non-stressed plants, which reduced the uptake of essential nutrients for plants. The highest fresh weight of plants and nutrient uptake potential was recorded in Sandalbar closely followed by JS-2002, which indicated these sorghum cultivars as salt tolerant. It is further concluded that the induction of the salt stress in the growth medium cause adverse effect on the growth and uptake of essential nutrients. It was observed that salt stress cause ion toxicity in sorghum plants. These results could be used in sorghum breeding programs to select the most tolerant cultivars. [ABSTRACT FROM AUTHOR]

Objective: To investigate the possible associations of angiotensin converting enzyme insertion or deletion genotypes and alleles with the risk of preeclampsia in Arab women., Methods: The case-control study was conducted from January 2016 to December 2017 at King Abdulaziz University Hospital and Maternity & Children Hospital, Jeddah, Saudi Arabia, and comprised pregnant women withpreeclampsia as cases and normal pregnant women as controls. Deoxyribonucleic acid was extracted and angiotensin-converting enzyme gene was amplified by polymerase chain reaction analysis and characterised through gel electrophoresis., Results: Of the 162 women, 68(42%) were cases and 94(58%) controls. The mean values of age, body mass index, and systolic and diastolic blood pressure were significantly different among the cases than the controls (p<0.05), but mean gestational age did not significantly differ between the groups (p>0.05). The distribution of the polymorphic variants of the angiotensin converting enz yme gene insertion/deletion was not significantly different between the groups (p>0.05). Also, genotype distribution and allelic frequencies were not significantly different between the groups (p>0.05)., Conclusions: For insertion/deletion polymorphism, no significant differences were detected in the genotype and allele frequencies or any of the inheritance models between preeclampsia patients and controls.

The genome sequence analysis of Bacillus thuringiensis serovar konkukian S4 has shown to contain two chitinases (Chi74, Chi39) and two chitin-binding proteins (CBP50 and CBP24). The Chi74, Chi39 and CBP50 have been characterized previously. The chitin-binding protein CBP24 was cloned and heterologously expressed in Escherichia coli. The recombinant protein was purified using a Ni-NTA purification system. The purified protein was used to study its substrate binding activity using crystalline chitin variants as substrates. The Bmax and Kd values have shown that it preferably binds to β-type of the crystalline chitin at a range of pH with peak activity between 5.5-7.5. To elucidate the role of CBP24 in the chitin degradation system of S4, the purified chitinases Chi74, Chi39 along with the ChiA from Serratia proteamcualans were used in different combinations with the CBP24 and chitinolytic activity was assayed. It was shown that the CBP24 acts synergistically with chitin degradation activity of bacterial chitinases non-specifically. Moreover, the CBP24 has shown antifungal activity against plant pathogenic fungi Fusarium oxysporum and Rhizoctonia solani. The present study will lead us to develop a technology for environmental friendly conversion of chitin to valuable products.

This paper presents an in silico characterization of the chitin binding protein CBP50 from B. thuringiensis serovar konkukian S4 through homology modeling and molecular docking. The CBP50 has shown a modular structure containing an N-terminal CBM33 domain, two consecutive fibronectin-III (Fn-III) like domains and a C-terminal CBM5 domain. The protein presented a unique modular structure which could not be modeled using ordinary procedures. So, domain wise modeling using MODELLER and docking analyses using Autodock Vina were performed. The best conformation for each domain was selected using standard procedure. It was revealed that four amino acid residues Glu-71, Ser-74, Glu-76 and Gln-90 from N-terminal domain are involved in protein-substrate interaction. Similarly, amino acid residues Trp-20, Asn-21, Ser-23 and Val-30 of Fn-III like domains and Glu-15, Ala-17, Ser-18 and Leu-35 of C-terminal domain were involved in substrate binding. Site-directed mutagenesis of these proposed amino acid residues in future will elucidate the key amino acids involved in chitin binding activity of CBP50 protein.