Mixing of Prosopis africana pods and corn cob exerts contrasting effects on the production and quality of Bacillus thuringiensis crude endoglucanase.

Recently, attention has shifted to the use of mixed lignocellulosic substrates for the production of cellulolytic enzymes. However, researchers have focused mainly on achieving increased enzyme yields while neglecting other properties of the enzymes when using such mixtures. In this first-ever report of the application of Prosopis africana pod (PAP) in cellulase production, we investigated the effect of its combination with corn cob (CC), as an inducing carbon source, on the amounts and quality of crude endoglucanase produced by Bacillus thuringiensis SS12. The organism was grown on PAP, CC or their 1:1% w/w mixture (MS) and the crude endoglucanases produced were tested for activity, hydrolytic efficiency, and thermostability. PAP supported the highest enzyme activity (0.138 U/mL) and its endoglucanase was the most effective in hydrolyzing CMC and filter paper while CC-derived endoglucanase was the best for hydrolysis of alkali-pretreated CC. Enzyme activity of MS-derived endoglucanase (0.110 U/mL) was intermediate to that of PAP and CC (0.091 U/mL) and was the most stable at elevated temperatures (70 and 80 °C). It also liberated the least amount of reducing sugars from all tested substrates. Combination of both the substrates, thus, favored enzyme production and thermostability but was detrimental to hydrolytic efficiency.

Effect of dietary supplement from mono-culture fermentation of Moringa oleifera seeds by Rhizopus stolonifer on hematology and markers linked to hypercholesterolemia in rat model.

Mono-culture fermentation by Rhizopus stolonifer could promote the healthiness of immune systems and cholesterol levels. Hence, we examined the effect of diet from mono-culture fermentation of Moringa oleifera seeds by R. stolonifer (MCF-MORS) on hematological parameters and fundamental indicators of hypercholesterolemia in rat. The animals were divided into six groups (n = 6). Group 1 was placed on basal diet. Group II, III, IV and V were placed on a basal diets supplemented with 7.5%, 15%, 22.5% and 30%, respectively, of MCF-MORS. Group VI was placed on basal diet fed with unfermented M. oleifera seeds (UF-MOS). The experiment lasted for eight weeks. The results revealed 7.5% MCF-MORS as better biological method to augment PCV, RBC and Hb count in animal model. Also, 7.5% and/or 15% MCF-MORS demonstrated highest levels in centrophils, neutrophils and eosinophils, whereas the levels of lymphocytes, basophils and monocytes showed no significant difference. Similarly, 7.5% and 15% MCF-MORS modulated LDL and HDL, respectively, better than UF-MOS; but showing no difference in cholesterol level. MCF-MORS also maintained architectural integrity of villi and splenocytes better than UF-MOS. We therefore concluded that diet from MCF-MORS at 7.5% and 15% modulates HDL, LDL, cholesterol and immune system-related disorders better than UF-MOS in rat model.

A study of Aspergillus niger- hydrolyzed cassava peel meal as a carbohydrate source on the histology of broiler chickens.

The purpose of this study is to investigate the effect of hydrolysed cassava peel inclusion as a replacement for maize in broiler chicken feedstuff on the histology of the internal organs of broiler chickens. Thirty six, two weeks old unsexed broiler chickens were used for the study in a feeding trial of forty two days. The chickens were randomly allocated to six dietary treatments A - F using a completely randomized design. Each treatment group contained two replicates of three broiler chickens. Group A chickens (A1 and A2) were fed with the control diet (0% hydrolyzed cassava peel as main carbon source). Groups B-E (in replicates 1 and 2) were administered with experimental diets containing 25%, 50%, 75%, 100% of hydrolyzed cassava peels respectively replacing maize while group F (F1 and F2) were fed with diet containing 100% unhydrolyzed cassava peels replacing maize as the main carbon source. Feed and water were supplied ad libitum for the six weeks feeding trials period. Vaccine and drugs were administered as at when due. At the end of the third week, two replicate per group were fasted for twelve hours and slaughtered. Samples of liver, kidney and heart were collected and tissue samples were taken for histological examinations. All the chickens in group F that fed on unhydrolyzed cassava peel recorded 100% mortality within the first six days of the feeding trials while those in groups A to E recorded 0% mortality. Histology of the kidney, heart and liver showed increasing mark of coagulative necrosis, degeneration of the hepatocytes and vacuolations due to the shrinking of the hepatocellular and cardiac tissues as the cassava inclusion level increases in feed. It is concluded that birds can be fed with maize replaced with up to 50% hydrolyzed cassava peel in chicken feeds without serious deleterious effects and that the wastes have useful products in animal nutrition. Also, the replacement added economic in chicken production. The hydrolysis has led to a reduction in the potency of cyanide in the peel thereby making it a safe and possible candidate in the production of chicken feeds.

Bioethanol potentials of corn cob hydrolysed using cellulases of Aspergillus niger and Penicillium decumbens.

Corn cob is a major component of agricultural and domestic waste in many parts of the world. It is composed mainly of cellulose which can be converted to energy in form of bioethanol as an efficient and effective means of waste management. Production of cellulolytic enzymes were induced in the fungi Aspergillus niger and Penicillium decumbens by growing them in mineral salt medium containing alkali pre-treated and untreated corn cobs. The cellulases were characterized and partially purified. Alkali pre-treated corn cobs were hydrolysed with the partially purified cellulases and the product of hydrolysis was fermented using the yeast saccharomyces cerevisae to ethanol. Cellulases of A. niger produced higher endoglucanase and exoglucanase activity (0.1698 IU ml(-1) and 0.0461 FPU ml(-1)) compared to that produced by P. decumbens (0.1111 IU ml(-1) and 0.153 FPU ml(-1)). Alkali pre-treated corn cob hydrolysed by cellulases of A. niger yielded 7.63 mg ml(-1) sugar which produced 2.67 % (v/v) ethanol on fermentation. Ethanol yield of the hydrolysates of corn cob by cellulases of P. decumbens was much lower at 0.56 % (v/v). Alkali pre-treated corn cob, hydrolysed with cellulases of A. niger is established as suitable feedstock for bioethanol production.