Rotimi A. Oderinde

Evaluation of the properties of yellow nutsedge (Cyperus esculentus) tuber oil

Abstract Non-drying oil extracted from the tuber of yellow nutsedge ( Cyperus esculentus ) of Nigerian origin has been analysed for its physical and chemical constants, lipid classes and fatty acid components of the lipid classes. Triglycerides constitute 95% of the lipid classes while polar lipids constitute the remaining 5%. The fatty acid component in the triglycerides of the yellow nutsedge tuber showed individual unsaturated acids to be: oleic, 75·72 ± 0·20%; linoleic, 11·64 ± 0·17%; linolenic, 0·64 ± 0·1%; and saturated fatty acids to be: palmitic, 10·21 ± 0·15%; stearic, 1·47 ± 087% and arachidic, 0·32 ± 0·04%. Percentages of individual fatty acid in the polar lipid were found to be: oleic, 46·9 ± 0·3%; linoleic, 35·3 ± 0·3%; linolenic, 2·6 ± 0·1%; palmitic, 12·4 ± 0·2%; stearic, 2·8 ± 0·1% and a trace amount of arachidic acid. The similarities of the yellow nutsedge oil, in some of these characteristics, to some edible vegetable oils of economic importance are discussed.

Determination of the triglyceride, phospholipid and unsaponifiable fractions of yellow nutsedge tuber oil

Abstract Lipid classes, the fatty-acid distribution in triglycerides and the composition of the triglyceride, phospholipid and unsaponifiable fractions of the tuber oil of yellow nutsedge ( Cyperus esculentus ) were studied. Oleic acid was the dominant fatty acid in the whole tuber oil, the triglycerides and 2-monoglycerides obtained from pancreatic lipase treatment and the phospholipids. Phospholipids in the tuber oil accounted for 5.4 ± 0.5% of the total, with a phosphorus content of 0.004%. Ethanolamine glycerophospholipid (22.0 ± 1.1%), serine glycerophospholipid (1.7 ± 0.1%), choline glycerophospholipid (35.0 ± 2.3%) and inositol glycerophospholipid (26.0 ± 1.4%) were detected and quantified. Hydrocarbons (20.57 ± 3.3%), waxes (2.01 ± 0.4%), sterol esters (3.89 ± 0.3%), higher aliphatic alcohols (3.51 ± 0.2%), triterpenoid alcohols (1.88 ± 0.3%) and sterols (14.56 ± 1.1%) were the constituents of the unsaponifiable fraction. Quantifications of the sterols and alcohols of the unsaponifiable fraction were carried out; β-sito-sterol was found to be the major sterol, while cycloartenol was the major terpene alcohol.

Analysis of the pulp and pulp oil of the Tucum (Astrocaryum vulgare Mart) fruit.

Abstract Pulp composition, lipid classes, fatty acid composition, fatty acid distribution in triglycerides and triglyceride composition of pulp oil from the fruit of the Astrocaryum vulgare (Mart) palm have been studied. Triglycerides were the major species, accounting for 86·8% of the oil. Palmitic and oleic acids were the dominant fatty acids in whole oil, triglycerides and in the 2-position of triglycerides. A. vulgare pulp oil contained a broad range of triglycerides, the major types of which were S 2 U (31·4mol.%) and SU 2 (43·1 mol.%). S 3 and U 3 accounted for 6·9mol.% and 18·6mol.%, respectively. Proximate analysis of pulp gave: protein, 5·9%; crude fibre, 5·7%; ash, 1·9%; carbohydrate, 19·5%; oil, 22·0% and moisture, 45·0%.

Analysis of the lipids and molecular speciation of the triacylglycerol of the oils of Luffa cylindrica and Adenopus breviflorus

Oils extracted from seeds of Luffa cylindrica and Adenopus breviflorus were evaluated, in order to study their chemical compositions and lipid profile. Oil content of seed of L. cylindrica was 390.10 ± 0.20 g/kg while that of A. breviflorus was 500.80 ± 0.70 g/kg. Iodine value of L. cylindrica was 147.01 ± 0.70 cg iodine/g while that of A. breviflorus was 126.50 ± 0.50 cg iodine/g. Seed as well as oils of L. cylindrica and A. breviflorus were found rich in K and Ca. C18:2 was the dominant fatty acid found in the oils while neutral lipids were the dominant lipid class. Sitosterol, beta-tocopherol, phytol, stigmasterol, and hydrocarbons were identified in the unsaponifiable matter of the oils using GC–MS. HPLC results revealed presence of glycolipids such as monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and digalactosylmonoacylglycerol. Phosphatidylethanolamine was the dominant phospholipids in the oils. Molecular speciation of triacylglycerol revealed presence of C38 (LLnLn) and C40 (LLLn/LnLnP/LnLnO) to be dominantly present in the oils.

Fatty Acid Composition and Lipid Profile of Diospyros mespiliformis, Albizia lebbeck, and Caesalpinia pulcherrima Seed Oils from Nigeria.

The screening of lesser-known underutilized seeds as source of food has been a way of finding solution to food insecurity in developing nations. In this regard, oil as a class of food was extracted from the seeds of Diospyros mespiliformis  (4.72 ± 0.2%), Albizia lebbeck  (6.40 ± 0.60%), and Caesalpinia pulcherrima  (7.2 ± 0.30%). The oils were finally analyzed for their fatty acid composition, lipid classes, fatty acid distribution in the lipid fractions, and molecular speciation of the triacylglycerols, glycolipids, and phospholipids. The fatty acid composition of the oils varied with C18:2 fatty acid being the most dominant in the oils. Neutral lipids were the most abundant lipid class found in the oils while molecular species of the triacylglycerol with equivalent carbon chain number C40 was majorly present in the oils of Diospyros mespiliformis and Caesalpinia pulcherrima. The present study presents lesser-known underutilized seeds as possible sources of food.

Chemical composition and molecular speciation of the triacylglycerol of the oils of Lonchocarpus sericeus and Lonchocarpus cyanescens

Proximate composition of the seeds and chemical analysis of the oils of Lonchocarpus sericeus and Lonchocarpus cyanescens were determined. The oil content of the seed of L. cyanescens is 29.71 ± 0.20% while that of L. sericeus is 28.00 ± 0.50%. The seeds as well as the oils of L. cyanescens and L. sericeus were found to be rich in K, Na and Fe. Linolenic (C18:3) and oleic (C18:1) acid are the dominant fatty acids while the neutral lipids the dominant lipid class in the oils. Phytol, sterols, beta-tocopherol and hydrocarbons were identified in the unsaponifiable matters of the oils using GC–MS. The HPLC results revealed the presence of glycolipids, which are monogalactosyldiacylglycerol, digalactosyldiacylglycerol, digalactosylmonoacylglycerol and monogalactosylmonoacylglycerol. Molecular speciation of the triacylglycerol revealed the presence of molecular species with equivalent carbon chain numbers C36 (L. sericeus) and C50 (L. cyanescens) to be dominantly present in the oils.

Solvent free hydroxylation of the methyl esters of Blighia unijugata seed oil in the presence of cetyltrimethylammonium permanganate

Extraction of oil from the seed of Blighia unijugata gave a yield of 50.82 ± 1.20% using hexane in a soxhlet extractor. The iodine and saponification values were 67.60 ± 0.80 g iodine/100 g and 239.20 ± 1.00 mg KOH/g respectively with C18:1 being the dominant fatty acid. Unsaturated methyl esters of Blighia unijugata which had been previously subjected to urea adduct complexation was used to synthesize methyl 9, 10-dihydroxyoctadecanoate via hydroxylation in the presence of cetyltrimethylammonium permanganate (CTAP). The reaction was monitored and confirmed using FTIR and GC-MS. This study has revealed that oxidation reaction of mono unsaturated bonds using CTAP could be achieved under solvent free condition.

A cobalt(II) complex of vitamin B1

Abstract Thiamine (Vitamin B) when phosphorylated gives thiamine pyrophosphate (coenzyme cocarboxylase) (Fig 1) which catalyzes the decarboxylation of a-keto acids. This catalysis is enhanced by the presence of divalent metal such as Mg2+, Mn2+, Cd+, Ni2+, etc. The relative positions of these metal ions in the catalytic efficiency trend depend on the source of the enzyme. For example, for pyruvate decarboxylase from yeasf3 the catalytic efficiency is Mg2+ > Mn2+ > Cd+ > Zn2+ > Fe2+ > Cd2+ while for pyruvate decarboxylase from wheat gem4 the order is Mg 2+ > Cd+ > Zn2+ > Fe 2+ > Ni 2+ > Cd 2+ and from transketolase yeastS the order is Mn2+ > Mg 2+ > Fe 2+ > Ni 2+ > Cd+. Quite naturally, one would like to know what role each metal ion plays in enzymatic processes.

Effects of Different Home Storage Conditions and Preservation on Some Chemical Constituents of Tomato (Lycopersicon Esculentum)

This study was conducted to investigate the effects of different home storage conditions and preservation on some chemical constituents of tomato (Lycopersicon esculentum). The experiment involved three post-harvest treatments comprising of fruits without preservative used as the control, fruits preserved with groundnut oil and fruits preserved with salt. All these were further divided into sub samples and subjected to different home storage conditions for the period of 8 weeks. The tomato samples were evaluated for changes in total solid, insoluble solid, pH, sugar, salt content, ascorbic acid and ash contents. Results obtained indicated that total soluble solid, insoluble solid, pH, sugar, salt, ascorbic acid and ash contents of fresh and dehydrated samples decreased with different storage conditions while their acidity showed an increase. Powdered tomato samples were found to withstand long term storage and their chemical constituents showed minimal change over the period of the study. The results revealed that preservation by powdering technique proved to be a better technique and worthy of further industrial investigation.

The composition of the pindo (Arecastrum romanozoffianum) fruit

Abstract The pulp and kernel composition, lipid classes, fatty acid composition and distribution of triglycerides and triglyceride composition of kernel fat from Arecastrum romanozoffianum palms grown in Nigeria have been studied. The kernel has a moderate fat content. Lauric acid was the dominant fatty acid in whole kernel fat, in kernel triglycerides and also in the 2-monoglycerides derived from triglycerides by pancreatic lipase hydrolysis. All the fatty acids in kernel triglycerides exhibited a preference for the combined 1,3-positions except for lauric acid which exhibited a specificity for the 2-position. The trisaturated triglycerides were the dominant glyceride type and the fatty acid compositions of the various glycerides fractions from AgNO 3 -TLC suggested a paucity of simple (monoacid) triglycerides and completely unsaturated triglycerides. Arecastrum romanozoffianum pulp consisted mainly of carbohydrate.