Annual Research & Review in Biology

Saccaromyces cervisiae, isolated from “tella”, may serve as potential strains for commercial beer production. The main objective of the current study was to isolate, identify and characterize potential yeast isolates from “tella”, which can substitute commercial beer yeast. “Tella” yeast isolates were isolated and identified using biochemical test. Qualities of isolates and physico-chemical characteristics of beer were also determined. The degree of contamination was analyzed. Six yeast isolates were identified and designated as S1, S2, S3, S4, S5, S6, and S7 (commercial yeasts). Yeast viability was determined in wort gravity of 12^op and 14^op and the results were found to be 89 and 83%, respectively,. All isolates showed good fermentative capacity. Isolates S1, S3, S4, S5 and S6 grew in 100, 130 and 150 ml/L of absolute ethanol. The flocculation potential of isolate S3 and S4 were 85% and 82%, respectively. Isolates S3 (4.09±.01 v/v %) and S4 (4.36±.04v/v %) showed statistically higher (p ≤ 0.05) concentration of alcohol than the other isolates.  Isolates S1, S5 and S6 showed significantly greater (p ≤ 0.05) original extract than the control. Isolates S5, S2 and S6 showed statistically greater (p ≤ 0.05) apparent extract than the other isolates. Isolates had statistically greater (p≤0.05) apparent degree of fermentation. The physicochemical and other parameters of beers, produced from these isolates, were comparable with those of the commercial S. cervisiae isolates. Other threshold substances found in the produced beer were within the standard values of commercial beer. Therefore, S. cervisiae isolates from “tella” may be used as a substitute for commercial yeast in beer production.

Autoxidation is considered as one of the main factors responsible for deterioration which occurs during manufacturing, storage, distribution and final preparation of foods. Changes caused by lipid oxidation not only resulting to off-flavor, but also resulting to loss of color, decrease product’s shelf life, nutritional loss and human diseases. Nowadays, edible films and coatings have attracted the considerable attention due to their potential to enhance food quality, food safety and their function as carrier for wide range of food additives specially antioxidants. In this study, the range of 1 to 20 mg/ml concentrations from Zataria multiflora essential oil (ZMEO) and Bunium persicum essential oil (BPEO) incorporated in to corn starch film were used. Antioxidant activity of the bioactive films were determined by 2,2- diphenyl-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethyl benzo thiazoline-6-sulphonic acid, ABTS) and total phenolic content assays. Results showed that the films incorporated with EOs had better antioxidant properties compared with control group and this effect was significantly improved with increasing EOs concentration (P < 0.05). These finding pointed out that incorporation of ZMEO and BPEO as natural antioxidant agents into corn starch film could be considered as a potential factors for using in active packaging.

The effects of dimethoate on pituitary prolactin cells of Heteropneustes fossilis was investigated in this study. The fish Heteropneustes fossilis were subjected to sub-lethal concentration of dimethoate - 2.24 mg/l i.e. 75% of 96 h LC₅₀ for short-term (24, 48, 72 and 96 h), and 1.00 mg/l i.e. 25% of 96 h LC₅₀ for long-term (6, 12, 24 and 36 d) exposure. Pituitary was removed from anaesthetised fish and fixed for histological examinations. H. fossilis exposed for short-term (96 h) at sub-lethal dimethoate concentration, exhibited marked changes in structure and staining properties of prolactin cells. PRL cells did not show much histological alterations after 24 h, however, after 96 h exposure exhibited severe vacuolization and nuclear pycnosis, indentation and deformity of nuclear boundaries. In long-term dimethoate exposure the PRL cells of Heteropneustes fossilis, exhibited low staining  response invisible vacuolization and distinct nuclear boundaries after 6 day. However,  severe vacuolization, pycnosis and the nuclear diameter reduction in PRL cells were noticed  after 24 d and 36 d exposures. The study concluded that dimethoate affects calcium regulating prolactin (PRL) cells and disturb the calcium homeostasis of fish which is important for fish health and their survival.

Aims: Effects of crushed date pits (DP) on growth performance, carcass traits and nutrient digestibility were studied on forty Baladi goat kids.

Methodology: All kids were male with an average body weight of 20 kg (S.D. = 0.27) at the beginning of the experiment. Animals were randomly divided into four groups of 10 kids each. Kids in each group received corn- soybean meal (SBM) total mixed rations (TMR). Rations were incorporated with DP at levels 0, 15, 30 and 45%, in the control and treatments from 2 to 4, respectively. All rations were isonitrogenous and isoenergetic. The growth experiment lasted 120 days. In the following week, 4 kids from each treatment were slaughtered.

Results: Kids fed DP at all levels consumed more (P<0.05) feed (0.81, 0.92, 0.91 and 0.92 kg for kids treatments one to four, respectively) but gained less (P<0.05) weight compared to those fed the control diet (33,117, 119,and 116 g/ day for treatments on to four, respectively). This same trend was found for the feed conversion (FC), carcass weight and dressing percentages. Feeding DP had no effects on external organs (hide, head and feet) (P=0.32) and thoracic organs (heart and lungs, HL) (P=0.36) and liver (P=0.45) weights when expressed as percent of empty body weight (EBW). Similarly, DP in kids' rations had no effects on carcass cuts: neck (P=0.39), shoulder (P=0.56), loin (P = 0.29) and legs (P = 0.51) average weights. However, DP decreased (P< 0.05) the abdomen fat of kids. Nutrients digestibility were depressed (P< 0.05) by DP feeding. For example, DM digestibility of control ration reduced from 71.1 to an average of 68.8%in rations incorporated with DP.

Conclusions: Inclusion of DP reduced the cost of rations by an average value of 11%. However, It can be concluded that feeding DP to fattening kids had no advantages in most of the tested parameters. Improving the nutritive value of DP through chemical or biological treatments could assure its value as a nonconventional feed ingredient in ruminant rations.

The experimental material for the present investigation was comprised of 38 genotypes of onion. These genotypes were sown in Randomized Complete Block Design with three replications, to estimate the genetic variability, heritability and genetic advance. Observations were recorded on the basis of ten random competitive plants selected from each genotype separately for morphological, yield and quality parameters were evaluated as per standard procedure. Analysis of variance revealed highly significant variance for all the traits depicting greater variability in the existing material. The mean performance of the genotypes revealed a wide range of variability for all the traits. The variation was highest for bulb yield per hectare followed by bulb yield per plant, plant height at 90 DAT, plant height at 60 DAT, plant height at 120 DAT, plant height at 30 DAT, days to maturity and bulb yield per plot. The PCV was higher than the GCV for all the characters. High PCV and GCV was observed for bulb yield per plant, neck thickness and pseudostem diameter,indicating greater diversity for these traits and their further improvement through selection. High heritability supplemented with high genetic advance as percentage of mean was manifested by bulb yield per plant followed by neck thickness, pseudostem diameter, polar diameter of bulb, number of leaves per plant at 120 DAT, pseudestem length, plant height at 120 DAT and equatorial diameter of bulb suggested that they can be improved through direct selection. Considerable variability was observed among the genotypes for foliage colour, foliage cranking, bulb shape and bulb colour. Foliage colour in green onion and shape and colour of onion bulb are most important characteristics to help customers in choosing cultivars on the market.