The Issue of Human Cloning: A Review in Semitic Religions’ Context

Human cloning has emerged as a new and innovative technology in the reproductive and therapeutic science in the recent past. So far it has not been practiced over human beings but owing to its huge potential and possible scope, it has attracted the attention of not only the masses (particularly the infertile couples and LGBTQs etc) but the other stakeholders including the religious scholars from worlds’ prominent religions have given their views on this technology in order to guide their followers. This paper examines and reviews the religious points of view on human cloning. For this purpose, three Semitic religions in the world i-e Judaism, Christianity, and Islām have been examined. As far as Islam is concerned, this portion has been divided into two broad sections elaborating the Shī‘ah and Sunnī schools’ opinions. Being an innovative topic, the religious teachings do not address it directly hence the injunctions related to the reproduction are most relevant to it. Three Semitic religions have been examined from the perspective of admissibility or non-admissibility of human cloning, the rationale behind the verdict on human cloning and the possible solutions to the issues and problems faced by the followers in the case of acceptance or rejection of this biomedical technology. Most of the religions emphasize over adaptability of the natural mode of reproduction only, where male and female genders contribute to the reproductive cycle. The Semitic religions reject the reproductive cloning generally. The religious experts need to conduct more focused and updated research before coming to any conclusion about the permissibility or non-permissibility of this technique.

Studies on Cellulases and Xylanases of Indigenous Yeast Strains

Lignocellulose (LC), a composite of cellulose, hemicellulose and lignin is considered as naturally occurring chemical feedstock. Pakistan being an agricultural country, generates huge amounts of LC substrates in the form of agricultural waste. Global demand for chemicals and insufficient supply of energy in Pakistan, necessitates comprehensive studies on the utilization of LC substrates. LC materials can be used as substrate for the production of plant cell wall degrading enzymes (PCWDEs) including industrially important enzymes, cellulase and xylanase. At present, bacteria and filamentous fungi are employed for the production of cellulases and xylanase on large scale, whereas, very few yeasts have been studied in this regard. Keeping in view the importance of yeast cellulase and xylanase, the present study was conducted on isolation, production and characterization and possible biotechnological application of indigenous yeast strains. The study was initiated with the isolation of yeast strains from environmental samples and retrieval from culture collection available at the Department of Microbiology, University of Karachi. Total 225 yeast strains were subjected to qualitative screening, as well as, quantitative screening for cellulase and xylanase. On the basis of titers of the enzymes, three yeast strains were selected for further studies, MK-157 and MK-160, for endoglucanase (EG) and Xylanase (Xyl) production, repectively, while MK-118 for EG, β-glucosidase (BGL) and Xyl production. The strain, MK-157, was identified on morphological and biochemical basis as Saccharomyces cerevisiae, and was confirmed on molecular basis using ITS primer and species specific primers. Production of EG from S. cerevisiae MK-157 was optimized through shake flask method by adopting one factor at a time (OFAT) strategy. Maximum production of EG from MK-157 was obtained at 30 °C with media pH 7.0 and 1% CMC. EG from MK-157 was characterized and the data revealed that enzyme optimally active at 30 °C under acidic pH in the presence of 1% CMC. The gene encoding EG was isolated, sequenced and submitted to Genbank with accession number MF871644 and KY660547. The strain, MK-160, was identified on morphological, cultural and biochemical basis as Candida tropicalis. The optimized conditions for Xyl production from MK-160 were temperature, 40 °C; pH, 7; and substrate concentration, 0.5%. Optimal activity of Xyl from MK-160 was observed at 40 °C under acidic condition and with 2% of beechwood xylan. Likewise, the strain, MK-118, was identified as C. tropicalison on the basis of morphological, cultural and biochemical tests. MK-118 was studied for coproduction of EG, BGL and Xyl. Production of all the three enzymes from C. tropicalis MK-118 was optimized, separately. Production parameters varied greatly for individual enzyme. Such as for EG and BGL production, cultivation at 40 °C under neutral conditions was maximum while 25 °C with acidic condition was considered as suitable for Xyl production. The highest titers of EG, BGL and Xyl from MK-118 were obtained in presence of 0.5% of CMC, 1.5% of salicin and 1% of xylan, respectively. Moreover, the parameters affect differently when enzyme preparations were characterized. The maximum activity of the EG and BGL was noted at 30 °C while Xyl worked optimally at 40 °C. BGL and Xyl from MK-118 showed maximum active with 1.5% salicin and xylan, respectively, while EG exhibited highest activity with 2% of CMC. Selected yeast strains and their enzymes were also studied for their possible biotechnological application. S. cerevisiae MK-157, C. tropicalis MK-118 and MK-160 were cultivated under submerged fermentation (SmF) of sugarcane bagasse (SB) and wheat bran (WB) and found to produce a multienzyme comprised of EG, BGL and Xyl. Under SSF of SB, the strains MK-157 and MK-118 were cultivated along with a pectinolytic strain, Geotrichum candidum AA-15 that led to significant increase in the production of pectinase. Similarly, the production of multienzyme preparation by the strains MK-118, MK-157 and MK-160 was also studied under solid-state fermentation (SSF) of peels of Citrus limetta (CL). The parameters affecting multienzyme preparation were studied by employing statistical tools, Plackett-Burman Design and Box-Behnken Design. The data inferred that the multienzyme preparation was able to efficiently hydrolyze a variety of pectin-rich and cellulose-rich LC substrates. Moreover, the preparation was also found suitable to be applied for the clarification of orange juice. Ethanol production and dye adsorption ability of strain MK-157 of S. cerevisiae, MK-118 and MK-160 of C. tropicalis were also evaluated. All the three strains produced ~5% of ethanol and absorbed more than 90% of an azo dye, congo red from aqueous solution. Therefore, the strains may appear as suitable candidate for future biotechnological applications.